LIBRARY OF CONGRESS DDDn4DS4bl PHILOSOPHICAL DISCUSSIONS BY CHAUNCEY WRIGHT WITH A BIOGRAPHICAL SKETCH OF THE AUTHOR CHARLES ELIOT NORTON i y A & NEW YORK HENRY HOLT AND COMPANY 1877 Copyright, 1876, by HENRY HOLT. ■II > II. S II- 1 - 1 ul \ 11 K, Ithaca, V \ John K. Trow & Son, Printers, -•05 J13 E ] I'<»rA / if? //£ PREFATOPvY NOTE. This volume contains the greater part of the published writ- ings of its author. The beginning of the article on "Lewes's Problems of Life and Mind," and the fragment on " Cause and Effect " are now published for the first time. CONTENTS PAGE Biographical Sketch Ob Chauncey Wright vii A Physical Theory of the Universe i Natural Theology as a Positive Science 35 The Philosophy of Herbert Spencer 43 Limits of Natural Selection 97 The Genesis of Species 128 Evolution by Natural Selection 168 Evolution of Self-Consciousness 199 The Conflict of Studies 267 The Uses and Origin of the Arrangements of Leaves in Plants 296 McCosh on Intuitions 329 Mansel's Reply to Mill 350 Lewes's Problems of Life and Mind 360 McCosh on Tyndall 375 Speculative Dynamics 385 Books Relating to the Theory of Evolution 394 German Darwinism 398 A Fragment on Cause and Effect 406 John Stuart Mill — A Commemorative Notice 414 Index 429 BIOGRAPHICAL SKETCH OF CHAUNCEY WRIGHT. BY CHARLES ELIOT NORTON. Chauncey Wright died in Cambridge, Massachusetts, on the 12th of September, 1875, aged forty-five years. His name was not widely known. He had written compar- atively little. A few essays by him on scientific subjects had appeared in "The Mathematical Monthly," and the " Memoirs" and " Proceedings of the American Academy of Arts and Sci- ences"; he had contributed several articles, mostly upon phil- osophical topics, to the "North American Review," and he had printed numerous briefer papers in "The Nation." His work gave evidence not only of a mind of rare power and un- usual balance,. but also of wide acquisitions and thorough in- tellectual discipline, and he had won recognition from compe- tent judges as a philosophical thinker of a high order, from whom much was to be expected. To collect his principal writings, and to present them in a form accessible to students was a duty to his memory, and in the interest of philosophy. Fragmentary, as of necessity such a collection must be, and but imperfectly representative of the scope of the author's mind, the general character of his philo- sophical opinions and method may clearly enough be learned from it. It seemed desirable to prefix to this selection from his writ- ings an account of the author, not merely to gratify the nat- viii CHAUNCEY WRIGHT. ural desire of his readers to know something of the man to whom they might owe the incitement of thought, but still more because the character of Chauncey Wright was no less remark- able than his intelligence, and was of such uncommon and ad- mirable quality that upon those who knew him intimately his death fell as a great misfortune, and has. left a void in their lives that can never be filled. The task of preparing this account has been assigned to me as one who knew him well, especially during the last fifteen years of his life, and who had enjoyed the happiness of his close and helpful friendship. The external events of his life were not striking, and all that need be told of them can be said in a few words. Chauncey Wright was born in Northampton, in the year 1830. His father and mother were of old New England stock, with such characters and habits as were the results of a long suc- cession of generations who had lived simply and seriously, transmitting from one to another the traditions of labor, fru- gality, domestic comfort, and intelligence. His father was an active man in his town, carrying on a successful country trade, and occupied with the various duties of the office of a deputy- sheriff of the county, a post which he filled for many years. Wright's boyhood was fortunate in the advantages common to New England country boys at a time when the conditions which have, during the present generation, wrought so rapid and great a change in American society, had hardly begun to manifest themselves. The circumstances of his life were em- inently wholesome. He was an affectionate, reserved, and thoughtful boy, fond of animals and plants, observant of their habits, and in general more interested in outdoor than indoor pursuits. He did not especially distinguish himself at school, except, perhaps, in mathematics and in the writing of compo- BIOGRAPHICAL SKETCH. ix sitions, which he often preferred to write in verse rather than in prose. No strong personal influence seems to have affected the natural development of his intelligence; and, though neither solitary nor unsocial, he worked out much by himself the problems and devices of his youth, and early displayed the solid independence of his mind and character. He had a se- rious disposition, and even in early years he, at times, suffered from a tendency toward melancholy. He entered Harvard College in 1848. His classical attainments were slight, and he took little interest in the study either of languages or of litera- ture. The bent of his mind was strong toward abstract pur- suits, and he applied himself chiefly to mathematics and phi- losophy, displaying the acuteness and originality of his intel- ligence in his themes and other written exercises. He had a certain inertness of temperament which caused the action of his mind to appear slow and difficult. But often when he seemed least active, he was engaged in reflection, and the want of brilliancy or vivacity of power was more than compen- sated for by solidity of acquisition, as well as by the assimila- tion of his knowledge with his thought. He learned slowly, but he knew whatever he learned. His memory was retentive, and well disciplined, so that its stores not only became abun- dant, but were also held in good order for service. One of the most marked features of his intellectual nature, even at this comparatively early date, was the steadiness and consistency of its growth. There was nothing desultory in the pursuit of his aims; and, though his efforts were often intermittent, they were not dispersed. His modesty and reserve combined with the nature of his interests to prevent him from being well known by any large circle of acquaintances; but the disinterestedness of his dispo- sition and the amiability of his temper endeared him to a few x CHAUNCEY WRIGHT. intimate friends, while his classmates generally felt for him more than ordinary regard and respect. Soon after leaving college, in 1852, he was appointed one of the computers for the recently established "American Ephem- eris and Nautical Almanac." By occasional contributions to the "Mathematical Monthly" and other journals, he grad- ually won repute as a mathematician and physicist of distin- guished ability and accomplishment. In 1863 he was made Recording Secretary of the American Academy of Arts and Sciences, a place which he held for seven years, and which gave opportunity not only for the exercise of his sound judg- ment in practical questions, but for the exhibition of critical discrimination in the editing of the Academy's " Proceedings." His attention gradually became more and more fixed upon the questions in metaphysics and philosophy presented in their latest form in the works of Mill, Darwin, Bain, Spencer, and others, and in 1864 he published in the "North American Review," then under my charge, the first of a series of phil- osophical essays, of which the last appeared only two months before his death, and of which it is not too much to say that they form the most important contribution made in America to the discussion and investigation of the questions which now chiefly engage the attention of the students of philosophy. From the time of his leaving college to his death, he resided, with brief intervals of absence, in Cambridge. In 1872, he spent a few months in Europe. In 1870 he delivered a course of University Lectures in Harvard College on the principles of Psychology. In 1874-75, he was instructor in Harvard College in Mathematical Physics. He lived all his life simply, frugally, and modestly. He had few wants, and he used a considerable part of his somewhat scanty means to add to the comfort of those who were dear to BIOGRAPHICAL SKETCH. xi him. He had what may be truly called an elevated nature, not remote from human interests, but above all selfishness or meanness. The motives by which the lives of common men are determined had little influence with him. He did not feel the spur of ambition, or the sting of vanity. No thought of personal advantage, no jealousy of others, affected his judg- ment or his conduct. His principles were so firmly established that his moral superiority seemed not so much the result of effort as the expression of what was natural to him. His sym- pathies were not stimulated by his mode of life, but they were keen, and so interpenetrated by his intelligence that in cases of need they made him one of the most helpful of men. He was, for instance, admirable as a nurse by the sick-bed, alike tender and firm; and while the touch of his hand and the modulation of his Voice afforded the invalid unwonted comfort and repose, the steadiness of his judgment gave the' supporting tone so often wanting in the sick-room. The same qualities brought him frequently into happy relations with children and with old people. If his imagination once felt the appeal, his adaptation of his strength to their weak- ness, of his multiplicity of resource to their need of enter- tainment, was so complete as to w T in for him the love of young and old. He was fond of games with children, and would devote himself to their amusement with unwearied pa- tience and spirit. He had great skill in sleight-of-hand, and frequently amused himself with finding out and reproducing the tricks of the most renowned jugglers. He would hardly have been suspected by a casual acquaintance to be a master in legerdemain; for his massive build and heavy proportions, and the absence of agility in his common movements, seemed to unfit him for performances of this sort. But, after seeing him display his dexterity, it was easily recognized as the out- xii CHAUNCEY WRIGHT. growth and indication of faculties already exercised in higher fields. The same fine touch and precise and delicate move- ment which were shown in his nursing, the same quick and ex- act vision which distinguished his observation as a physicist were exhibited in his feats of parlor magic. He brought his keen analytical powers to bear on the seemingly mysterious processes of jugglers or of spiritualists; he used his knowledge of mechanics in the construction of toys, and applied his mathematical genius to the invention and performance of mar- velous games and puzzles of cards. I dwell thus at length on what might seem a mere trivial accomplishment, not only because it affords a vivid illustration of marked personal traits, but more because it was the means by which he gave concrete and visible expression to certain mental qualities trained to rare perfection in higher fields of exertion. His temper was naturally calm, and he early attained a de- gree of self-discipline that enabled him to keep it under com- plete control. He was fond of debate and argument, and the full force of his mind was brought out through the animation of talk, more than in the solitary exercise of writing. Yet he was seldom ruffled by controversy, and never made ungenerous use of his strength, or forced his opponent to pass through the Caudine Forks of unwilling concession and acknowledgment of defeat. This control of his own temper secured that of his adversary. To argue with him was a moral no less than an intellectual discipline. The words he used of Mill apply with equal fitness 4o himself. " He sincerely welcomed intelligent and earnest opposition with a deference due to truth itself, and to a just regard of the diversities in men's minds from differ- ences of education and natural dispositions. These diversities even appeared to him essential to the completeness of the ex- BIOGRAPHICAL SKETCH. xiii animation which the evidences of truth demand. Opinions positively erroneous, if intelligent and honest, are not without their value, since the progress of truth is a succession of mis- takes and corrections. Truth itself, unassailed by .erroneous opinion, would soon degenerate into narrowness and error. The errors incident to individuality of mind and character are means, in the attrition of discussion, of keeping the truth bright and untarnished, and even of bringing its purity to light." It was in this spirit that Wright himself carried on the dis- cussions in which he engaged. He early learned that truth is a double question; and in the pursuit of truth, which was the controlling motive of his life, he disciplined himself by the study of opposing opinions. As he himself said, " Men are born either Platonists or Aristotelians ; but by their education through a more and more free and enlightened discussion, and by progress in the sciences, they are restrained more and more from going to extremes in the directions of their native biases." And this general remark may be applied with fitness to him- self. For while his intellectual operations were directed by a spirit of observation and experiment, which, though training the judgment and imagination in habits of accuracy, might .also have a tendency to direct the attention to exclusive views of truth, he was on the other hand in all matters of specula- tion, to use a phrase of Mr. Mill's, essentially a seeker, testing every opinion, and recognizing the difficulties which adhere to them all. He exhibited that union of science and. of philoso- phy which is the highest distinction of the leading thinkers of our time, and which hereafter will be indispensable for all who may succeed in deepening the current of thought or in open- ing for it new channels. It was a marked quality of his genius as a thinker, that its xiv CHA UNCE Y WRIGHT. springs were mainly fed from other sources than those of books. He was no wide reader; but, making himself master of a few comprehensive books, he gained from them, by re- flection upon them, much more than their mere contents. He was never a persistent and systematic student; but he was es- sentially a persistent and systematic thinker. During his college life he had been a judicious reader of Emerson and of Lord Bacon, but in the years of his early manhood, while he was accumulating large stores of observa- tion and reflection, two or three books, similar in interest, but widely different in spirit and in method, were of special interest and importance to him, — chiefly Sir William Hamilton's Dis- sertations and Lectures, and Mill's Political Economy and his System of Logic. The repute and influence of Hamilton as a metaphysician and psychologist have undoubtedly declined since the publication, in 1865, of Mill's Examination of his Philosophy, — a philosophy, which professed to combine in an original form the German and French developments of the earlier Scotch reaction against Locke and Hume, with the demonstrations of modern science in respect to the necessary limits of knowledge. Hamilton had, however, succeeded previously not only in re-awakening among English students a fresh interest in metaphysics, but also in exercising a strong influence upon the general current of philosophical opinion. It was his great service, and one which will always deserve recognition, whatever be the ultimate verdict upon his special doctrines, that he produced a real revival of interest in a sub- ject of fundamental importance which for a generation at least had ceased to receive due attention, and that he forced once more upon the consciousness of his generation the conviction that a true Psychology is, in the words of Mr. Mill, "the in- dispensable scientific basis of Morals, of Politics, and of the BIOGRAPHICAL SKETCH. xv science and art of Education," and that upon the resolution of the difficulties of metaphysics, using the word in its proper sense, depends the assurance of the solid foundation of all knowledge. For this stimulus, and for this conviction, Wright, like many others, was indebted to his early studies of Hamil- ton. But he had studied Hamilton too thoroughly, and with too much clearness of mind, not to have become aware, even before Mill's exposure of them, of some at least of the weak points and inconclusive determinations of his system. But Mill's work was much more than a simple refutation of the errors of Hamilton. In accomplishing this, he did much to re-establish, and upon more solid foundations than before, certain principles in philosophy of which the validity had seemed to be shaken. He showed that the determination of the vexed problems of metaphysics was to be sought in a- properly scientific, and not in an a priori, or spiritualist psy- chology. His work went far to determine the mutual depend- ence of mental philosophy and of experimental science, the general recognition of which has already become effective in determining their respective courses of advance. The doctrine of experience may not yet be the dominant doctrine of the En- glish school of psychologists; but the fact is obvious, that the recent independent investigations of science, and the rapid and unforeseen developments of knowledge, have tended to confirm its main propositions, and to strengthen its claim to accept- ance. With this doctrine in psychology, the ill-named but generally well-understood doctrine of utilitarianism in morals is closely associated, so closely indeed that one may be said to be in great measure dependent on the other. Whatever contributes to the support of either, contributes more or less directly to the support of both. It may not be correct to assert, that if either be overthrown the other must fall with it; but it is at least xvi CHAUNCEY WRIGHT. certain, that the validity of a great part of each depends on evidence common to both. The consistency among the postu- lates of psychology, and morals, has never been so clearly mani- fest, and has never received such valuable exposition, as during the last twenty years, mainly through the efforts of English in- vestigators and thinkers, with Mill and Darwin at their head. The effect of Mill's doctrine upon the direction of Wright's thought was confirmed ,by that of Darwin's work on The Origin of Species by means of Natural Selection. The strong moral element in the works of both writers found a warm re- sponse in his own nature. The entire candor, the love of truth, the disinterested search for it, the patience of investiga- tion, the accuracy of statement, the modesty of assertion, characteristic of both these masters, were in entire harmony with his own mental traits. The conclusions and the theories of Mill and Darwin may be disputed, may be overthrown, but their respective methods of investigation and of statement are of such excellence, and their desire for truth so sincere and im- personal, that their works would remain as models of scientific investigation and philosophic inquiry even though they should lose their doctrinal authority. The questions opened and partially solved by these authors were those which chiefly occupied Wright during the last ten years of his life. The rare combination in him of a genius for reflection, disciplined by long exercise, with great natural powers of observation, and with unusually wide and accurate scientific attainments, fitted him to deal with them not merely as a re- porter of other men's thought, but as an original investigator, capable himself of making additions to the sum of knowledge. The position which he occupied as a philosopher is the stand- point common to one of the two fundamental divisions of the philosophic world; namely, that of the assumption of the uni- BIOGRAPHICAL SKETCH. xvii versality of physical causation. It cannot be stated better than in his own words. " The very hope of experimental philoso- phy/' he says, " its expectation of constructing the sciences into a true philosophy of nature, is based on the induction, or, if you please, the a priori presumption, that physical causation is universal ; that the constitution of nature is written in its actual manifestations, and needs only to be deciphered by ex- perimental and inductive research ; that it is not a latent in- visible writing, to be brought out by the magic of mental an- ticipation or metaphysical meditation. Or, as Bacon said, it is not by the ' anticipations of the mind,' but by the ' interpre- tation of nature,' that natural philosophy is to be constituted; and this is to presume that the order of nature is decipherable, or that causation is everywhere either manifest or hidden, but never absent." The methods of'this interpretation of nature or, in~other words, of this discovery of truth, he regarded as those of all true knowledge ; namely, the methods of induction from the facts of particular observation. This was his position in respect to the much-debated problem of metaphysical caus- ation, or the question of what are called "real connections be- tween phenomena as causes and effects, which are independent of our experiences, and the invariable and unconditional se- quences among them." " To those," I cite his own words, " who have reached the positive mode of thought, the word 'cause' simply signifies the phenomena, or the state of facts, which pre- cede the event to be explained, which make it exist, in the only sense in which it can clearly be supposed to be made to exist ; namely, by affording the conditions of the rule of its occur- rence. But with those," he adds, u . who have not yet attained to this clear and simple conception of cause, a vague but fa- miliar feeling prevails, which makes this conception seem very inadequate to express their idea of the reality of causation. xviii CHAUNCEY WRIGHT. Such thinkers feel that they know something more in causa- tion than the mere succession, however simple and invariable this may be. The real efficiency of a cause, that which makes its effect to exist absolutely, seems, at least in regard to their own volitions, to be known to them immediately." "But," he goes on, after an interval, "that certain mental states of which we are conscious are followed by certain external ef- fects which we observe is to the sceptical schools a simple fact of observation. These thinkers extend the method of the more precisely known to the interpretation of what is less precisely known, interpreting the phenomena of self-consciousness by the methods of physical science, instead of interpreting phys- ical phenomena by the crudities of the least perfect though most familiar of all observations, the phenomena of volition."* It is not to be assumed, from the phrase in the preceding extract concerning those "who have reached the positive mode of thought," that Wright classed himself with any spe- cific school of so-called Positivists. He used the term positive, as it is now commonly employed, as a general appellation to designate the whole body of thinkers who in the investigation of nature hold to the methods of induction from the facts of observation, as distinguished from the a priori school, who seek in the constitution of the mind the key to the inter- pretation of the external world. It was only in this sense that he himself was a positivist. So too with regard, to his use of the word "sceptical." In his employment of it, it had no di- rect theological significance. It meant with him the temper of mind which puts no confidence in assertion unsupported by the evidence of experience; it meant the temper of question- ing and investigation as opposed to that of concluded opinion; * North American Review, 106, p. 286, notice of Peabody's Positive Philosophy, January, 1868. BIOGRAPHICAL SKETCH. xix the temper in which the unknown remains matter of inquiry, not of dogmatism, and to which the unknowable, or that which lies plainly outside the range of human faculties, is of no con- cern save as matter of sentiment. To the quality of this sen- timent he gave great weight as a test of the worth of individ- ual character. His scepticism rested upon the proposition, that the highest generality, or universality, in the elements, or connections of elements, in phenomena, is the utmost reach both in the power and the desire of the scientific intellect. There was nothing aggressive in such scepticism as this, except so far as it led him to expose the fallacious arguments of the supporters of the orthodox metaphysics. The sympathetic, quality of his nature showed itself in his respect for individual beliefs sincerely held. He felt, to use his own words, "that the subordinate, almost incidental value that some traditional metaphysical issues, like the ultimate nature of the connection of mind and matter, and of cause and effect, and the depend- ence of life on matter, have in the view of the scientific psy- chologist, is with difficulty comprehended by those who ap- proach the subject from a religious point of view." He had no liking for the iconoclasts who would destroy ancient faiths in the hearts of those who are incapable of substituting, with good j effect on their lives, rational convictions in the place of senti- mental beliefs. He had confidence in the constant and pro- gressive extension of the field of knowledge; but he did not believe that the question of the origin and destiny of things would ever be included within its limits. If asked for his spec- ulations on these topics, that so greatly exercise the curiosity of the race, he would have been very likely to reply with the words of Newton, which were among his favorite apothegms, "Hypotheses 11011 Jingo." In the year 1870, Mr. Wright published the first of a series xx CHAUNCEY WRIGHT. of papers, of which the last appeared but a short time before his death, expository of the true nature of the doctrine of Natural Selection, of its various applications, and of its rela- tions to common metaphysical speculations. In the first of these articles, which had the form of a review of Mr. Wal- lace's contributions to the Theory of Natural Selection, Mr. Wright touches upon the application of the principles involved in the doctrine of Natural Selection to the development of the mental powers of man. The full importance of the topic did not, however, appear till the publication, more than two years afterward, of his most considerable contribution to philosophy, his essay on the Evolution of Self-Consciousness, in which a natural explanation is given of the chief phenomena of human consciousness, involving the' refutation of many of the main propositions of mystical metaphysics or idealism. In 1871, he published a paper on the Genesis of Species, in reply to Mr. St. George Mivart's attack on the theory of Natural Selection. The vigor and effectiveness of his defense of the theory led to the republication of this essay in England, at Mr. Darwin's instance, and compelled Mr. Mivart to attempt to make good his position in a communication to the " North American Review," the journal in which Mr. Wright's article originally appeared. To this reply Mr. Wright rejoined in the succeed- ing number of the "Review," July, 1872.* In these discussions of the problems of modern research, and other shorter papers on similar topics, published for the most part in "The Nation," Mr. Wright showed the wide reach of his thought, his powers of keen analysis, and the large store of his acquirements. His training in the sound scientific method of investigation gave precision to his statement of the * In his recently published work, entitled " Lessons from Nature as manifested in Mind and Matter," Mr. Mivart reprints his reply to Mr. Wright's criticisms, but fails to notice Mr. Wright's rejoinder. BIOGRAPHICAL SKETCH. xxi inductions of philosophic thought. He carried the scientific method into the region of reflection. In respect to all matters concerning which the facts necessary for the formation of opin- ion were not known, or had been but insufficiently observed, he held a suspended judgment. He never seemed to have a prepossession in favor of or against any opinion, concerning which the testimony of experience was doubtful, and the evi- dence of fact apparently inconsistent. But his thought was by no means limited to the topics which philosophy derives from the exact or the natural sciences. The main attraction of science and philosophy to him was not on the side of abstract truth, but much more on the application of truth to the life and conduct of man. The questions of morality, of politics, of jurisprudence, of education, in the light thrown on them by psychology and by experience, were those which in his later years were continually assuming an increasing share of his attention. And in his treatment of these questions he displayed the most eminent trait of his genius, and the highest result of the discipline of his philosophic powers, — I mean a good practical judgment, or the quality of wisdom. Chauncey Wright was in the true sense a wise man. I do not assert, that, in the ordering of his own life, he was always guided by the considerations of wisdom. In some important respects his self-control was greatly deficient in steadiness. Few, indeed, of the wisest men have succeeded in conforming their lives in all respects to their principles. Wisdom more frequently manifests itself in objective relations, than in the complete mastery of , personal dispositions, and a consistently judicious regulation of/ conduct. And, in all matters in which the interests of others were involved, Mr. Wright's judgment was one of the most trustworthy. His sympathetic nature gave him the power to enter into moods of character and conditions of feeling widely xxii CHAUNCEY WRIGHT. diverse from his own, while his judgment in each particular in- stance was the result of inductions of large experience and careful reflection. Instant as the expression of his opinions might be, there was nothing of haste in their formation. Emo- tion, sentiment, opinion, all rested with him on a rational foun- dation. I should give a false image, if, in thus speaking. I were to convey the impression of anything dry or forma.ly deliberate in his intercourse with others. He was, especially in his later years, always ready and fluent in talk, easily ani- mated, accessible to the ideas of others, neither preoccupied with his own reflections to the exclusion of external sugges- tions, nor using the predominant weight of his own intelligence to crush the slighter fabric of the thought of his companions. He had the modesty of the philosopher in happy combination with his just self-confidence, and the vigor of his moral senti- ment was as evident in the manner as in the substance of his discourse. I have referred to his tendency in early life to mel- ancholy. He was never wholly free from occasional periods in which some defect of physical organization or constitution showed itself in uncontrollable mental depression. But he was for. the most part cheerful, and often gay. He was an easy and equable companion, and the lighter regions of life and thought were as open and accessible to him, as the grave solitudes in which he habitually dwelt. Those who knew him best will most clearly discern the fact that his published writings, able as they are, and deserving of the respect due to high qualities of thought, fall short of being a satisfactory expression, even of the purely intellectual part of his nature. The action of his mind in composition was labo- i rious, and his style was often too compact of thought, and not sufficiently relieved by the lighter graces of expression. His writings and his oral lectures sometimes required closer atten- BIOGRAPHICAL SKETCH. xxiii tion on the part of readers or hearers than it would have been , well to demand of them. His thought, indeed, was never obscure ; but it was too condensed, and at times too profound to be readily followed. His own ability misled him, and he did not always estimate aright the average incapacity of un- trained intelligence to follow a process of exact reasoning. But nothing of this defect was to be found in his conversation,which was constantly lighted up by the pleasant play of a suggestive humor, that often added a happy and unexpected stroke where- with to clinch the point of argument. In talk, the readiness of his intelligence was not less remarkable than its force ; and the abundance and variety of his resources not less surprising than their accuracy. Whatever he knew was at his command, and his knowledge extended over many fields with which he might not have been supposed to be familiar. One could hardly turn to him with a question on any topic, however remote from his ordinary studies, without receiving from him an answer that seemed as if he already had devoted special attention to the subject now for the first time presented. The method of his thought was so excellent that new topics fell naturally into their right positions, and received immediate illustration from previous acquisitions, made originally without reference to any such application. With such capacities as his, and with such training as he had given them, the growth of his mind was con- stant. There was no period* to his progress, and what he had done seemed but the beginning and assurance of the greater things of which he was capable. His sudden death in the full- ness of power was a loss to be mourned by all who have at heart the interests of philosophy ; that is, by all to whom the highest interests of man are of concern. PHILOSOPHICAL DISCUSSIONS. A PHYSICAL THEORY OF THE UNIVERSE * In 1811 Sir William Herschel communicated to the Royal Society a paper in which he gave an exposition of his famous hypothesis of the transformation of nebulae into stars. " As- suming a self-luminous substance of a highly attenuated nature to be distributed through the celestial regions, he endeavored to show that, by the mutual attraction of its constituent parts, it would have a tendency to form itself into distinct aggrega- tions of nebulous matter, which in each case would gradually condense from the continued action of the attractive forces, until the resulting mass finally acquired the consistency of a solid body, and became a star. In those instances wherein the collection of nebulous matter was very extensive, subordinate centres of attraction could not fail to be established, around which the adjacent particles would arrange themselves; and thus the whole mass .would in process of time be transformed into a determinate number of discrete bodies, which would ultimately assume the condition of a cluster of stars. Her- schel pointed out various circumstances which appeared to him to afford just grounds for believing that such a nebulous sub- stance existed independently in space: He maintained that the phenomena of nebulous stars, and the changes observable in the great nebula of Orion, could not be satisfactorily ac- counted for by any other hypothesis. Admitting, then, the existence of a nebulous substance, he concluded, from indica- tions of milky nebulosity which he encountered in the course of his observations, that it was distributed in great abundance throughout the celestial regions. The vast collections of neb- * From the North American Review, July. 1864. 2 PHILOSOPHICAL DISCUSSIONS. ulre which he had observed, of every variety of structure and in every stage of condensation, were employed by him with admirable address in illustrating the modus operandi of his hypothesis. " * Laplace, in his Systeme du Monde, applied this hypothesis, by an ingenious but simple use of mechanical principles, to the explanation of the origin of the planetary bodies, and of the general features of their movements in the solar system. Supposing the original nebulous mass to receive a rotatory motion by its aggregation, he showed that this motion would be quickened by a further contraction of the mass, until the centrifugal force of its equatorial regions would be sufficient to balance their gravitation, and to suspend them in the form of a vaporous ring. Again, supposing this revolving ring to be broken, and finally collected by a further aggregation into a spherical nebulous mass, he showed, in the same way, how the body of a planet, with its system of satellites, might be formed. The material and the original motions of the planets and their satellites could thus, he supposed, be successively produced, as the nebula gradually contracted to the dimensions of the sun. No scientific theory has received a fairer treatment than the nebular hypothesis. Arising as it did as a speculative conclu- sion from one of the grandest inductions in the whole range of physical inquiry, — connecting as it does so many facts, though vaguely and inconclusively, into one system, — it pos- sesses, what is rare in so bold and heterodox a view, a veri- similitude quite disproportionate to the real evidence which can be adduced in its support. The difficulties which ordina- rily attend the reception of new ideas, were in this case removed beforehand. The hypothesis violated no habitual association of ideas, at least among those who were at all competent to comprehend its import. Though resting on a much feebler support of direct evidence than the astronomical theories of Copernicus, Galileo, and Kepler, it met with a cordial recep- tion from its apparent accordance with certain preconceptions, of the same kind as those, which, though extrinsic and irrele- * Grain's History of Physical Astronomy. A PHYSICAL THEORY OF THE UNIVERSE. 3 vant to scientific inquiry, were able to oppose themselves suc- cessfully for a long time to the ascertained truths of modern astronomy. The test of conceivableness, the receptivity of the imagina- tion, is a condition, if not of truth itself, at least of belief in the truth; and in this respect the nebular hypothesis was well founded. It belonged to that class of theories of which it is sometimes said, "that, if they are not true, they desenie to be true." A place was already prepared for it in the imaginations and the speculative interests of the scientific world. We propose to review briefly some of the conditions which have given so great a plausibility to this hypothesis. In the first place, on purely speculative grounds, this hypothesis, as a cosmological theory, happily combines the excellences of the two principal doctrines on the origin of the world that were held by the ancients, and which modern theorists have discussed as views which, though neither can b^ established scientifically, have no less interest from a theological point of view; — namely, first, the materialistic doctrine, that the world, though finite in the duration of its orderly successions and changes, is infinite in the duration of its material substance; and, secondly, the spiritualistic doctrine, that matter and form are equally the effects, finite in duration, of a spiritual and eternal cause. At first sight the nebular hypothesis seems to agree most nearly with the materialistic cosmology, as taught by the greater number of the ancient philosophers; but the resem- blance is only superficial, and, though the hypothesis possesses those qualities by which the ancient doctrine was suited to the limitations and requirements of the poetical imagination, yet it does sot involve that element of fortuitous causation which gave to the ancient doctrine its atheistic character. In the nebular hypothesis the act of creation, though- reduced to its simplest form, is still essentially the same as tha't which a spir- itualistic cosmology requires. The first created matter filling the universe is devoid only of outward and developed forms, but contains created within it the forces which shall determine every change and circumstance of its subsequent history. 4 PHILOSOPHICAL DISCUSSIONS. The hypothesis being thus at once simple and theistic appeals to imagination and feeling as one which at least ought to be true. Such considerations as these doubtless determined the fate of another ancient cosmological doctrine, which, though adopted by Aristotle, was regarded with little favor by an- cient philosophers generally. For there could be but little support, either from poetry or religion, to the doctrine which denied creation, and held that the order of nature is not, in its cosmical relations, a progression toward an end, or a develop- ment, but is rather an endless succession of changes, simple and constant in their elements/though infinite in their combi- nations, which constitute an order without beginning and with- out termination. While this latter doctrine was not necessarily materialistic, like that which has been so termed, and which was more gen- erally received among the ancients, and though it has the greater scientific simplicity, yet it fails on a point of prime im- portance, so far as its general acceptance is concerned, in that it ignores the main interest which commonly attaches to the problem. Cosmological speculations are, indeed, properly con- cerned with the mode or order of the creation, and not with the fact of the creation itself. But that the first cosmogonies were written in verse shows the almost dramatic interest which their themes inspired. "In the beginning" has never ceased to charm the imagination; and these are almost the only words in our own sacred cosmogony to which the modern geologist has not been compelled to give some ingenious inter- pretation. That there was a beginning of the order of natural events and successions may be said to be the almost universal faith of Christendom. The nebular hypothesis, conforming to this preconception and to the greatest poetic simplicity, passed the ordeal of un- scientific criticism with remarkable success. Not less was its success under a general scientific review. A large number of facts and relations, otherwise unaccounted for, become expli- cable as at least very probable consequences of its assumptions ; and these assumptions were not, at first, without that indepen- A PHYSICAL THEORY OF THE UNIVERSE. s dent probability which a true scientific theory requires. The existence of the so-called nebulous matter was rendered very probable by the earlier revelations of the telescope ; and, though subsequent researches in stellar astronomy have rather dimin- ished than increased the antecedent probability of the theory, by successively resolving the nebulae into clusters of star-like con- stituents, — suggesting that all nebulosity may arise from defi- ciency in the optical powers of the astronomer rather than in- here in the constitution of the nebulae themselves, — and thereby invalidating the scientific completeness of the theory, yet the plausible explanations which it still affords of the constitution of the solar system have saved it from condemnation with a considerable number of ingenious thinkers. With astrono- mers generally, however, it has gradually fallen in esteem. It retains too much of its original character of a happy guess, and has received too little confirmation of a precise and definite kind, to entitle it to rank highly as a physical theory. But there are two principal grounds on which it will doubt- less retain its claim to credibility, till its place is supplied, if this ever happens, by some more satisfactory account of cos- mical phenomena. To one of these grounds we have just alluded. The details of the constitution of the solar system present, as we have said, many features which suggest a phys- ical origin, directing inquiry as to how they were produced, rather than as to why they exist, — an inquiry into physical, rather than final causes ; features of the same mixed character of regularity and apparent accident which are seen in the details of geological or biological phenomena; features not sufficiently regular to indicate a simple primary law, either physical or teleological, nor yet sufficiently irregular to show an absence of law and relation in their production. The approximation of the orbits of the planets to a common plane, the common direction of their motions around the sun, the approximation of the planes and the directions of their rotations to the planes of their orbits and the directions of their revolutions, the approximative^ regular distribution of their distances from the sun, the relations of their satellites to the general features of the primary system, — these are some 6 PHILOSOPHICAL DISCUSSIONS. of the facts requiring explanations of the kind which a geolo* gist or a naturalist would give of the distribution of minerals, or stratifications in the crust of the earth, or of the distribution of plants and animals upon its surfa ce, — phenomena indicating complex antecedent conditions, in which the evidence of law is more or less distinct. The absence of that perfection in the solar system, of that unblemished completeness, which the ancient astronomy assumed and taught, and the presence, at the same time, of an apparently imperfect regularity, compel us to re- gard the constitution of the solar system as a secondary and derived product of complicated operations, instead of an archetypal and pure creation. Such is one of the grounds on which the nebular hypothesis rests. The other is of a more general character. The ante- cedent probability which the theory lacks, from its inability to prove by independent evidence the fundamental assumption of a nebulous matter, is partially supplied by a still more gen- eral hypothesis, to which this theory may be regarded as in some sort a corollary. We refer lo the "development hypoth- esis," or "theory of evolution," — a generalization from cer- tain biological phenomena, which has latterly attracted great attention from speculative naturalists. This hypothesis has been less fortunate in its history than that of the astronomical one. Inveterate prejudices, insoluble associations of ideas, a want of preparation in the habits of the imagination, were the unscientific obstacles to a general and ready acceptance of this hypothesis at its first promulgation. Though in one of its applications it is identical with the nebular hypothesis, yet, in more direct application to the phenomena of the gen- eral life on the earth's surface, it appears so improbable, that it has hitherto failed to gain the favor which the nebular hy- pothesis enjoys. Nevertheless, as a general conception, and independently of its specific use in scientific theories, it has much to recommend it to the speculative mind. It is, as it were, an abstract statement of the order which the intellect expects to find in the phenomena of nature. "Evolution," or the progress "from the homogeneous to the heterogeneous, and from the simple to the complex," is the order of the prog- A PHYSICAL THEORY OF THE UNIVERSE, j ress of knowledge itself, and is, therefore, naturally enough, sought for as the order in time of all natural phenomena. The specific natural phenomena in which the law of "evolution" is determined by observation as a real and established law, are the phenomena of the growth of the individual organism, ani- mal or plant. As a law of psychological phenomena, and even of certain elements of social and historical phenomena, it is also well established. Its extension to the phenomena of the life of the races of organized beings, and to the successions of life on the surface of the earth, is still a speculative conclusion, with about the same degree of scientific probability that the nebular hypothesis possesses. And lastly, in the form of the nebular hypothesis itself, it is extended so as to include the whole series of the phenomena of the universe, and is thus in generality, if accepted as a law of nature, superior to any other generalization in the history of philosophy. As included in this grander generalization, the nebular hy- pothesis receives a very important accession of probability, provided that this generalization can be regarded as otherwise well founded. As a part of the induction by which this gen- eralization must be established, if it be capable of proof, the nebular hypothesis acquires a new and important interest. We are far from being convinced, however, that further in- quiry will succeed in establishing so interesting a conclusion. We strongly suspect that the law of "evolution" will fail to appear in phenomena not connected, either directly or re- motely, with the life of the individual organism, of the growth of which this law is an abstract description. And, heterodox though the opinion be, we are inclined to accept as the sound- est and most catholic assumption, on grounds of scientific method, the too little regarded doctrine of Aristotle, which banishes cosmology from the realm of scientific inquiry, re- ducing natural phenomena in their cosmical relations to an infinite variety of manifestations (without a discoverable tend- ency on the whole) of causes and laws which are simple and constant in their ultimate elements.* * The laws or archetypes of nature are properly the laws of invariable or unconditional sequence in natural operations. And it is only with the objective relations of these laws, 8 PHILOSOPHICAL DISCUSSIONS. In rejecting the essential doctrine of " the theory of evolu- tion " or "the development hypothesis," we must reserve an important conclusion implied in the doctrine, which we think is its strongest point. There are several large classes of facts, apparently ultimate and unaccountable, which still bear the marks of being the consequences of the operations of so-called secondary causes, — in other words, have the same general character as phenomena which are known to be the results of mixed and conflicting causes, or exhibit at the same time evidence of law and appearance of accident. That such facts should be regarded as evidence of natural operations still un- known, and perhaps unsuspected, is, we think, a legitimate conclusion, and one which is presupposed in "the theory of evolution," and in the nebular hypothesis, but does not ne- cessitate the characteristic assumptions of these speculations. An extension of the sphere of secondary causes, even to the explanation of all the forms of the universe as it now exists, or of all the forms which we may conceive ever to have existed, is a very different thing from adopting the cosmological doc- trine of the "development theory." Naturalists who have recently become convinced of the necessity of extending nat- ural explanations to facts in biology hitherto regarded as ulti- mate and inexplicable, but who are unwilling to adopt the cosmological view implied in the "development theory," have adopted a new name to designate their views. "The deriva- tive theory," or "derivative hypothesis," implies only con- tinuity, not growth or progress, in the succession of races on the surface of the earth. Progress may have been made, as a matter of fact, and the evidence of it may be very conclusive in the geological record; but the fact may still be of secondary importance in the cosmological relations of the phenomena, and the theory ought not, therefore, to give the fact too prom- inent a place in its nomenclature. as constituting the order of nature, that natural science is concerned. Their subjective relations, origin, and essential being belong to the province of transcendental meta- physics, and to a philosophy of faith. According to this division, there can never arise any < onflict between science and faith ; for what the one is competent to declare, the other is incompetent to dispute. Science should be free to determine what the order of nature is, and faith equally free to declare the essential nature of causation or creation. A PHYSICAL THEORY OF THE UNIVERSE. g That the constitution of the solar system is not archetypal, as the ancients supposed, but the same corrupt mixture of law and apparent accident that the phenomena of the earth's sur- face exhibit, is evidence enough that this system is a natural product ;* and the nebular hypothesis, so far as it is concerned with the explanation simply of the production of this system, and independently of its cosmological import, may be regarded as a legitimate theory, even on the ground we have assumed, though on this ground the most probable hypothesis would assimilate the causes which produced the solar system more nearly to the character of ordinary natural operations than the nebular hypothesis does. With a view to such assimilation, and in opposition to "the theory of evolution" as a general- ization from the phenomena of growth, we will now propose another generalization, which we cannot but regard as better founded in the laws of nature. We may call it the principle of counter-movements, — a principle in accordance with which there is no action in nature to which there is not some counter- action, and no production in nature from which in infinite ages there can result an infinite product. In biological phenomena this principle is familiarly illustrated by the counter-play of the forces of life and death, of nutrition and waste, of growth and degeneration, and of similar opposite effects. In geology the movements of the materials of the earth's crust through the counteractions of the forces by which the strata are elevated * This argument for physical causes is apparently the reverse of that which Laplace derived from the regularities of the solar system and the theory of probabilities ; but in reality the objects of the two arguments are distinct. For the legitimate conclusion from Laplace's computation is, not that the solar system is simply a physical product, but that the causes of its production could not have been irregular. The result of this computation was a probability of two hundred thousand billions to one that the regular- ities of the solar system aro not the effects of chance or irregular causes. The gist of this argument is to prove simplicity in the antecedents of the solar sys- tem ; and, had the proportion been still greater, or infinity to one, the argument might have proved a primitive or archetypal character in-the movements of this system. It is therefore in the limitations, and not in the magnitude, of this proportion, that there is any tendency to show physical antecedence. Hence it is not from the regularities of the solar system, but from its complexity, that its physical origin is justly inferred. Regarding the law of 'causation as universal, since, if not implied in the very search for causes, it is at least the broadest and the best established induction from natural phenomena, we conclude that the appearance of accident among the manifestations of law is proof of the existence of complex antecedent conditions and of physical causa- tion, and that the absence of this appearance is proof of simple and primitive law.' IO PHILOSOPHICAL DISCUSSIONS. and denuded, depressed and deposited, ground to mud or hardened to rock, are all of the compensative sort ; and the movements of the gaseous and liquid oceans which surround the earth manifest still more markedly the principle of counter- movements in the familiar phenomena of the weather. Of what we may call cosmical weather, in the interstellar spaces, little is known. Of the general cosmical effects of the opposing actions of heat and gravitation, the great dispersive and concentrative principles of the universe, we can at present only form vague conjectures; but that these two principles are the agents of vast counter-movements in the formation and destruction^ of systems of worlds, always operative in never- ending cycles and in infinite time, seems to us to be by far the most rational supposition which we can form concerning the matter. And indeed, in one form or another, the agencies of heat and gravitation must furnish the explanations of the circumstances and the peculiarities of solar and sidereal sys- tems. These are the agents which the nebular hypothesis supposes; but by this hypothesis they are supposed to act under conditions opposed to that general analogy of natural operations expressed by the law of counter-movements. Their relative actions are regarded as directed, under certain condi- tions, toward a certain definite result; and this being attained, their formative agency is supposed to cease, the system to be finished, and the creation, though a continuous process, to be a limited one. It should be noticed, however, in favor of the nebular hypothesis, that its assumptions are made, not arbitrarily, in opposition to the general analogy of natural operations, but because they furnish at once and very simply certain mechan- ical conditions from which systems analogous to the solar system may be shown to be derivable. The dispersive agency of heat is supposed to furnish the primordial conditions, upon which, as the heat is gradually lost from the clouds of nebulous matter, the agency of gravitation produces the condensations, the motions, and the disruptions of the masses which subse- quently become suns and planets and satellites. And if the mechanical conditions assumed in this hypothesis could be A PHYSICAL THEORY OF THE UNIVERSE. It shown to be the only ones by which similar effects could be produced, the hypothesis would, without doubt, acquire a degree of probability amounting almost to certainty, even in spite of the absence of independent proof that matter has ever existed in the nebulous form. But the mechanical conditions of the problem have never been determined in this exhaustive manner, nor are the con- ditions assumed in the nebular hypothesis able to determine any other than the general circumstances of the solar system, such as it is supposed to have in common with similar systems among the stars. A more detailed deduction would probably require as many separate, arbitrary, and additional hypotheses as there are special circumstances to be accounted for. Until, therefore, it can be shown that the nebular hypothesis is the only one which can account mechanically for the agency of heat and gravitation in the formation of special systems of worlds, like the solar system, its special cosmological and me- chanical features ought to be regarded with suspicions, as opposed to the general analogy of natural operations. We propose to criticise this hypothesis more in detail, and to indicate briefly the direction in which we believe a better solution of the problem of the construction of the solar system will be found. But before proceeding, we must notice an able Essay, by Mr. Herbert Spencer, the first in his Second Series of " Essays : Scientific, Political, and Speculative." In this essay on the "Nebular Hypothesis,',' and in the fol- lowing one on " Illogical Geology," Mr. Spencer has attempted the beginning of that inductive proof of the general theory of "evolution" to which we have referred. Undoubtedly the clearest and the ablest of the champions and expounders of this theory, he brings to its illustration and defense an extraordi- nary sagacity, and an aptitude for dealing with scientific facts at second hand, and in their broad general relations, such as few discoverers and adepts in natural science have ever exhib- ited. For dealing with facts which are matters of common observation, his powers are those of true genius. In the essays following those with which we are immediately interested, and particularly in the essay on "The Physiology of Laughter," I2 PHILOSOPHICAL DISCUSSIONS. and in the review of Mr. Bain's work on "The Emotions and the Will," he displays the true scope of his genius. In psy- chology, and in the physiology of familiar facts, we regard his contributions to philosophy as of real and lasting value. He is deficient, however, in that technical knowledge which is neces- sary to a correct apprehension of the obscure facts of science; and his generalizations upon them do not impress us as so well founded as they are ingenious. In his resume of the facts favorable to the nebular hypoth- esis, he has committed sundry errors of minor importance, which do not in themselves materially affect the credibility of the hypothesis, but illustrate the extremely loose and un- certain character of the general arguments in its support. A singular use is made of a table, compiled by Arago, of the inclinations of the planes of the orbits of the comets. The legitimate inference from this table is, that there is a well- marked accumulation of the planes of these orbits at small inclinations to the plane of the ecliptic. In considering the directions of the poles of these planes, we ought to find them equally distributed to all parts of the heavens, in case the orbits of the comets bear no relation to those of the planets or to each other. Instead of this, we find a marked concen- tration of these poles about the pole of the ecliptic, showing that their planes tend decidedly to coincide with the ecliptic. But Mr. Spencer has drawn from this table a conclusion directly the reverse of this. Assuming, as we cannot but believe on insufficient evidence, that the directions of the major axes of the orbits of those comets whose planes are greatly inclined to the ecliptic have nearly as great an inclina- tion as they can have, or that they are nearly as much inclined to the ecliptic as the planes of the orbits themselves, he regards the table of the inclinations of the planes of the orbits as indi- cating, at least for such comets, the directions of their axes, and draws thence the conclusion, that there is a well-marked concentration about the pole of the directions of the axes of the cometary orbits, and hence, that the regions in which the aphelia of comets are most numerous are above and below the sun, in directions nearly perpendicular to the ecliptic. This A PHYSICAL THEORY OF THE UNIVERSE. !3 conclusion, though the reverse of that which is legitimately drawn from Arago's table, is not inconsistent with it; and if Mr. Spencer were correct in his assumption concerning the directions of the axes of highly inclined orbits, the table would show that there are really two well-distinguished systems of comets, the one belonging to the general planetary system, and the other, Mr. Spencer's, forming a system by itself, — an axial one, at right angles with the general system. But either conclusion serves the purpose of the discussion equally well. For what Mr. Spencer wished to show was, that the relations of the comets to the solar system are not utterly fortuitous and irregular, but such as indicate a systematic con- nection; and this is undoubtedly true, since the connection of the planetary and cometary orbits is even more direct and inti- mate than Mr. Spencer has suspected. The inference which Arago's table warrants is, then, another in that interesting series of facts which some physical theory, whether nebular or not, by "evolution" or by involution, may some day ex- plain. The greater number of the arguments, old and new, which Mr. Spencer adduces in support of his thesis, do not apply specifically to the nebular hypothesis in particular, but are simply an enumeration of the facts which go to show the ex- istence of physical connections, of an unknown origin and species, in the solar system. In his handling of the me- chanical problems of the nebular genesis, Mr. Spencer has succeeded no better than his predecessors. In attempting to account for the exceptions to a general law which the rota- tions of the outer planets, Uranus and Neptune, and the revo- lutions of their satellites, exhibit, — the great inclinations of the planes of these rotations and revolutions to the planes of the orbits of the primaries,— Air. Spencer makes what appears to us a very erroneous assumption, and one from which the conclusion he wishes to draw by no means inevi- tably follows. It is one of the few successes of the nebular hypothesis, that it accounts in a general way for the fact that the planes and directions of the rotations of the planets, and the revolutions I 4 PHILOSOPHICAL DISCUSSIONS. of their satellites, nearly coincide with the planes and direc- tions of their own orbital motions. A ring of nebulous matter, detached by its centrifugal force from the revolving mass of the nebula, contains within it the conditions by which the direction, and even the amount, of the rotation of the result- ing planet is determined; and this direction is the same as that of the revolution of the ring. The ring must originally be of a very thin, quoit-shaped form, even if it be composed of separate, independently moving parts ; otherwise the planes of the orbits of the several parts would not pass through or near to the centre of attraction in the central nebula, and the parts must either pass through each other from one to the other surface of the ring, which would tend, along with other forces, to flatten it to the requisite thinness. Hence, a hoop- shaped fluid ring, or one thinner in the directions of its radii than in a direction perpendicular to its general plane, could not exist. Much less could such a ring be detached by its self-sustaining centrifugal force from the body of the nebula. The nebula must necessarily be flattened in its equatorial regions to a sharp, thin edge by the centrifugal force of its revolution, before those regions could be separated to form a ring. The supposition, therefore, which Mr. Spencer's inge- nuity has devised to account for the anomalies presented in the rotations and the secondary systems of Uranus and Nep- tune, — a hoop-shaped ring, with a less determinate tendency to rotation in forming a planet, — is untenable. But this is not all. Supposing such a form possible, and even if the parts of the ring did not move among themselves, or press upon one another so as to flatten the ring, yet the direction of its tendency to rotation in contracting to a planet is just as deter- minate as in the quoit-shaped ring. We have gone thus into detail, to show the vague and uncertain character of the mechanical arguments of the neb- ular hypothesis when they deal with details in the constitution of the solar system. In his treatment of recent discoveries and views in stellar astronomy, we think Mr. Spencer more fortunate. We agree with him in believing the current opin- ion to be an error, which represents the nebulae as isolated A PHYSICAL THEORY OF THE UNIVERSE. IS sidereal systems, inconceivably remote, and with magnitudes commensurate with the Galactic system itself. There are many reasons for believing that the nebulas belong to this system, and that they are, in general, at no greater distance from us than the stars themselves. We think, also, with him, that the actual magnitudes of the stars are probably of all degrees, and that their apparent magnitudes do not generally indicate their relative distances from us. We would even go further, and maintain, as both a priori most probable, and most in accordance with observation, that the free bodies of the uni- verse range in size from a grain of dust to masses many times larger than the sun, and that the number of bodies of any magnitude is likely to bear some simple proportion to the smallness of this magnitude, itself. Star-dust is not at all distasteful to us, except in the form of nebular boluses. For reasons which will appear hereafter, the smaller bodies are not likely to be self-luminous; and star-dust is probably the cause of more obscuration than light in the stellar universe. That gaseous and liquid masses also exist with all degrees of rarefaction or density, dependent on the actions of heat and gravitation, is also, we think, very probable; and the three states of aggregation in matter doubtless play important parts in the cosmical economy. Before leaving Mr. Spencer, to attend more immediately to the merits of the nebular hypothesis, we wish to adopt from him an estimate of the value of certain ideas in geology, the bearing of which on our subject is not so remote as it may at first sight appear to be. Geology has not yet so far detached itself from cosmological speculations as to be entitled to the rank of a strictly positive science. The influence of such speculations upon its termi- nology, and upon the forms of the questions and the directions of the researches of its cultivators, is still very noticeable, and shows how difficult it is to start anew in the prosecution of physical inquiries, or completely to discard unfounded opin- ions which have for a long time prevailed. Greater sagacity is sometimes required to frame wise questions, than to find their answers. Geologists still continue to collate remote strati- 1 6 PHILOSOPHICAL DISCUSSIONS. fications as to their stratigraphical order, mineral composition, and fossil remains, as if these were still expected to disclose a comparatively simple history — simple at least in its outlines — of the changes which the life of our globe has undergone. A story, dramatically complete from prologue to epilogue, was demanded in the cosmological childhood of the science, and its manhood still searches in the fragmentary and mutilated records for the history of the creation. But doubtless the story is as deficient in the dramatic unities, as the record itself is in continuity or completeness. Referring to Mr. Spencer's admirable essay on "Illogical Geology" for our reasons, we will simply state our belief that nothing in the form of a complete or connected history will ever be deciphered from the geological record. " Only the last chapter of the earth's history has come down to us. The many previous chapters, stretching back to a time immeasurably remote, have been burnt, and with them all the records of life we may presume they contained. The greater part of the evidence which might have served to settle the development controversy is forever lost ; and on neither side can the arguments derived from geology be conclusive." We must not ascribe to Mr. Spencer, however, our opinion, that, even if this record were more complete, we should not necessarily be the wiser for it. According to Mr. Spencer's views, the first strata, had they been preserved, would have contained the remains of protozoa and protophytes ; but, for aught we dare guess, they might have contained the footprint: of archangels. Evidence of progress in life through any ever so consider- able portion of the earth's stratified materials would not, in our opinion, warrant us in drawing universal cosmical con- clusions therefrom. Alternations of progress and regress rela- tively to any standard of ends or excellence which we might apply, is to us the most probable hypothesis that the general analogy of natural operations warrants. Nevertheless, as we have already intimated, we accept the purely physical portion of the "development hypothesis," both in its astronomical and biological applications, but would much prefer to designate the doctrine in both its applications by the name we have already quoted. This name, "the derivative hypothesis," simply con- A PHYSICAL THEORY OF THE UNIVERSE. jj notes the fact that, in several classes of phenomena hitherto regarded as ultimate and inexplicable, physical explanations are probable and legitimate. But it makes no claim to rank with the names of the Muses as a revealer of the cosmical order and the beginning of things. We are aware that in thus summarily rejecting the cosmo- logical import of the nebular hypothesis, along with its special physical assumptions, and retaining only its fundamental as- sumption, that the solar system is a natural product, we leave no provision to meet a demand which we allow, and we ought to justify this insolvency by proving the bankruptcy of the hypothesis whose debts we thus assume. It would be difficult, however, to prove that this hypothesis cannot fulfill the promise it has so long held out. Much more difficult would it be to supply its place with an equally plausible theory. But our ob- ject should not be to satisfy the imagination with plausibility. If we succeed in satisfying our understanding with the outlines of a theory sufficiently probable, we shall have done all that in the present state of our knowledge can reasonably be de- manded. The agencies of heat and gravitation acting, however slowly, through the ages of limitless time, and according to the law of counter-movements, or according to the analogy of the weather, constitute the means and the general mode of operation from which we anticipate an explanation of the general consti- tutions of solar and sidereal systems. There comes to our aid a remarkable series of speculations and experiments recently promulgated upon the general sub- ject of the nature and origin of heat, and under the general name of " The Dynamical Theory of Heat," the principles of which we shall endeavor briefly to explain. It is a funda- mental theorem in mechanical philosophy, that no motion can be destroyed, except by the production of other equivalent mo- tions, or by an equivalent change in the antecedent conditions ot motion. If we launch a projectile upward, the motion which we impart to it is not a new creation, but is derived from forces or antecedent conditions of motion of a very com- plicated character in our muscular organism. It would be T 8 PHILOSOPHICAL DISCUSSIONS, confusing to consider these at the outset; but if we look simply to the motion thus produced in the projectile itself, we shall gain the best preliminary notions as to the character of the phenomena of motion in general. The projectile rises to a certain height and comes to rest, and then, unless caught upon some elevated support, like the roof of a house, it returns to the ground with constantly accelerated motion, till it is sud- denly brought to rest by collision with the earth. In this series of phenomena we have in reality only a series of com- mutations of motions and conditions of motion. The project- ile is brought to rest at its greatest elevation by two forms of commutation. A small part of its motion is given to the air, and the remainder is transformed into the new condition of motion represented by its elevated position. The latter may remain for a long time permanent in case the projectile is caught at -its greatest elevation upon some support. But a small auxiliary movement dislodging the projectile may at any time develop this condition of motion into a movement nearly equal to that which the projectile first received from our mus- cles. The small part that is lost in the air or other obstacles still exists, either in some form of motion or in some new con- ditions of motion, and the much greater part which disap- pears in the collision of the projectile with the earth is con- verted into several kinds of vibratory molecular movements in the earth, in the air, and in the projectile itself; and per- haps in part also in various new molecular conditions of mo- tion. If we designate by the word "power" that in which all forms of motion or antecedent conditions of motion are equivalent, we find that in the operations of nature no "power" is ever lost. Nor is there any evidence that any new "power" is ever created. It would be foreign to our purpose to follow into their ramifications the speculations by which this interest- ing theorem has been illustrated in many branches of physical inquiry. We are immediately interested only in the three principal and most general manifestations of "power" in the universe, namely, the movements of bodies, the movements in bodies, and the general antecedent conditions of both. A PHYSICAL THEORY OF THE UNIVERSE. I9 The proposition that the principal molecular motions in bodies are the cause which produces in our nerves the sensa- tions of heat, or that they are what we denominate " the sub- stance of heat," — the objective cause of these sensations, — has long been held as a very probable hypothesis; and has latterly received experimental confirmations amounting to complete proof. The three principal manifestations of "power" in the universe are then, more specifically, the. mass- ive motions of bodies in translation and rotation, their molecu- lar motions, or heat ; and the principal antecedent condition of both, or gravitation. In comparing these as to their equivalence we obtain a sum of "power," which remains invariable and indestructible by the operations of nature. It remains to determine the precise relations of their equivalence, and what the operations are by which they are converted into each other. The mechanical equivalent of heat is a quantity which has been very accurately determined by experiment. By means of it we may very readily compute what amount of heat would be produced if a given amount of massive motion were con- verted into heat by friction or otherwise ; or conversely, what amount of massive motion could be produced by the conver- sion of a given amount of heat into mechanical effect ; but it is unnecessary to our purpose to give the precise method of this computation. The mechanical equivalent of gravitation is another quantity or relation depending on the changes of what is called the "potential" of gravitation, or the sum of the ratios of the masses to the distances apart of the gravitating bodies. The "power" of motion is a relation or quantity, commonly called the "living force " of motion, and depends on the mass and on the square of the velocity of the moving body. The living forces of all moving bodies, minus the potentials of their forces of gravitation, plus the mechanical values of their heat, equal to a constant quantity, — is the precise formula to which our cosmical speculations should conform. It will be impossible, however, to make any other than a very general use of this precise law. What concerns us more 2 o PHILOSOPHICAL DISCUSSIONS. nearly is the consideration of the natural operations by which these manifestations of "power" are converted into each other. . The origin of the sun's light and heat is a problem upon which speculative ingenuity has long been expended in vain. The metaphysical conclusion, that the sun is composed of pure fire, or of fire per se, the very essence of fire, is one of many illustrations of the ingenious way in which speculation covers its nakedness with words, and can really mean, we imagine, only that the. sun is very hot. That the sun, like any other body, must grow cooler by the expenditure of heat, is without doubt an indisputable proposition; and the question, how this heat is restored to it, is thus a legitimate one. The nebular hypothesis explains how the primitive heat in the sun and in other bodies could be generated by the condensation of the original nebulous mass, in which the heat is supposed to have been originally diffused ; but it affords no explanation of the manner in which this heat could be sustained through the ages that must have elapsed since the nebular genesis must have been completed. There are no precise means of estimating the amount of heat contained in the sun, since the capacity for heat of the materials which compose it are unknown ; but from general analogy it may safely be assumed that the sun must grow cooler at a sensible rate, unless its heat is in some way re- newed. Concerning the rate of its expenditure of heat, and the means which the dynamical theory of heat proposes to supply the loss, we will quote from the interesting lectures of Professor Tyndall, "On Heat considered as a Mode of Motion." "The researches of Sir J. Herschel and M. Pouillet have informed ns of the annual expenditure of the sun as regards heat, and by an easy calculation we ascertain the precise amount of the expenditure which falls to the share of our planet. Out of 2,300 million parts of light and heat the earth receives one. The whole heat emitted by the sun in a minute would be competent to boil 12,000 millions of cubic miles of ice- cold water. How is this enormous loss made good ? Whence is the sun's heat derived, and by what means is it maintained ? No combustion, no chemical affinity with which we are acquainted, would be competent to produce the temperature of the sun's surface. Besides, were the sun A PHYSICAL THEORY OF THE UNIVERSE. 2 \ a burning body merely, its light and heat would assuredly speedily come to an end. Supposing it to be a solid globe of coal, its combustion would only cover 4,600 years of expenditure. In this short time it would burn itself out. What agency, then, can produce the temperature and maintain the outlay ? We have already regarded the case of a body falling from a great distance towards the earth, and found that the heat generated by its collision would be twice that produced by the combustion of an equal weight of coal. How much greater must be the heat developed by a body falling towards the sun ! The maximum velocity with which a body can strike the earth [arising from the earth's attraction] is about 7 miles a second ; the maximum velocity with which it can strike the sun is 390 miles a second. And as the heat developed by the collision is proportional to the square of the velocity destroyed, an asteroid falling into the sun with the above velocity would generate about 10,000 times the quantity of heat generated by the combustion of an asteroid of coal of the same weight. "Have we any reason to believe that such bodies exist in space, and that they may be rained down upon the sun ? The meteorites flashing through our air are small planetary bodies, drawn by the earth's attrac- tion, and entering our atmosphere with planetary velocity. By friction against the air they are raised to incandescence, and caused to emit light and heat. At certain seasons of the year they shower down upon us in great numbers. In Boston [England] 240,000 of them were ob- served in nine hours. There is no reason to suppose that the planetary system is limited to vast masses of enormous weight ; there is every reason to believe that space is stocked with smaller masses, which obey the same laws as the large ones. That lenticular envelope which sur- rounds the sun, and which is known to astronomers as the zodiacal light, is probably a crowd of meteors ; and, moving as they do in a resisting medium, they must continually approach the sun. Falling into it, they would be competent to produce the heat observed, and this Would constitute a source from which the annual loss of heat would be made good. The sun, according to this hypothesis, would be continually grow- ing larger ; but how much larger ? Were our moon to fall into the sun, it would develop an amount of heat sufficient to cover one or two years' loss ; and were our earth to fall into the sun, a century's loss would be made good. Still, our moon and our earth, if distributed over the surface of the sun, would utterly vanish from perception. Indeed, the quantity of matter competent to produce the necessary effect would, during the range of history, produce no appreciable augmentation of the sun's magni- tude. The augmentation of the sun's attractive force would be more ap- preciable. However this hypothesis may fare as a representant of what is going on in nature, it certainly shows how a sun might be formed and maintained by the application of known thermo-dynamic principles." * Appendix to Lecture XII. p. 455. 22 PHILOSOPHICAL DISCUSSIONS. This part of our inquiry — how gravitation and motion are converted into heat — is receiving the amplest illustration and discussion from physicists at the present time ; and, though the somewhat startling conclusions we have quoted are still too new to be generally credited, they are too well founded in ex- periment and the general analogies of natural phenomena to be passed lightly by. The second part of our inquiry — how heat is refunded, in the eternal round of cosmical phenomena, into the antecedent conditions of motion, or to the conditions which preceded the production of the motions that are converted into heat — is a subject to which physicists have given little attention. In- deed, the cosmological ideas which prevail in geological inqui- ries beset this subject also, and impede inquiry. The order of nature is almost universally regarded as a progression from a determinate beginning to a determinate conclusion.* The dynamical theory of heat lengthens out the process better, perhaps, than the nebular hypothesis alone; but both leave the universe at length in a hopeless chaos of huge, dark masses, — ruined suns wandering in eternal night. It seems not to have occurred to physicists to inquire what becomes of the heat the generation of which requires so great an expenditure of motion. The heat is, in another form, the same motion as that which is lost by the fallen bodies. It is radiated into space, while the bodies remain in the sun ; but this radiation is still the same motion in other bodies, in the luminiferous ether, or in the diffused matters of space. It can- not be lost from the universe, and must either accumulate in diffused materials or be converted into other motions or into new conditions of motion. But if the solid bodies of the uni- verse are gradually collected at certain centres, and their mo- tions are diffused in the form of heat throughout the gaseous materials of space, what do we gain ? How do we by such a conclusion avoid the ultimate catastrophe which we regard as the reductio ad absurdum of a scientific theory ? How do we thereby constitute that cycle of movements which we regard as characteristic of all natural phenomena ? Perhaps we have been somewhat too hasty in adopting the conclusion that the A PHYSICAL THEORY OF THE UNIVERSE. 23 fallen bodies must necessarily remain in the sun, and grad ually augment its mass. Let us, therefore, examine this point more closely. The principles of the steam-engine afford a clew to the converse process we are in search of, by which heat may be refunded into mechanical effects and conditions. The mechan- ical effects of the expanding power of steam are only partially developed in the work which the engine performs. This work, converted back to heat by friction or otherwise, would be in- sufficient to reproduce the same effects in the form of steam. The remaining power consists in the motions and the power of expansion with which the steam escapes from the engine. This is lost power ; but if it should be allowed to develop itself by an expansion of the steam into an indefinitely extended vacuum, the molecular motions of the particles of the steam would gradually, and on the outside of the expanding vapor- ous mass, be converted into velocities or massive motions ; the vapor itself would be converted back into water, or even be frozen into snow, and the particles of this water or snow would, at the top of the expanding cloud, finally come to rest by the force of gravitation. A part, therefore, of the lost power of the heat which escaped in steam would be converted into that antecedent condition of motion represented by elevation above the attracting mass of the earth or by gravitation ; a part would continue to manifest itself as velocity or massive motion ; and the remainder would still continue to exert an outward press- ure in the form of heat in vapor. This development would continue so long as the steam continued to discharge itself into the indefinitely extended vacuum we have supposed. The rain or snow falling from the top of the cloud would convert its gravitative power back again into motion, which, again arrested by collision with the earth, would suffer other trans- formations in the endless round. In the actual case, where the steam escapes into the air instead of a vacuum, the phe- nomena would be less simple. The history of its heat would become involved with the grander phenomena of the weather, — phenomena that may be regarded as typical of that cosmical weather, concerning the laws of which we must inquire in con- sidering what becomes of the sun's heat. 2 4 PHILOSOPHICAL DISCUSSIONS. This heat is capable, provided it could all be so expended, of lifting the amount of matter which, by falling into the sun, is supposed to produce it, to the same height from the sun as that from which the fallen bodies may be supposed to have descended. This follows from the general mechanical princi- ples we have stated. But how is this lifting effected ? What is the Titanic machinery by which the sun performs this labor ? The velocity with which a body falling from the interstellar spaces enters the body of the sun is sufficient, when converted to heat by friction and the shock, to convert the body itself into vapor, even if the body be composed of the least fusible of materials. The heat thus produced is not, however, con- fined to the fallen matter. A large portion is imparted to the matter already in the sun ; but parts, no doubt, both of the projectile and of the resisting material are vaporized. The atmosphere immediately surrounding the sun contains the va- pors of many of the most refractory metals that are known, as we learn from that wonderful instrument, the spectroscope. And this is made evident by the absorption from the sun's luminous rays of certain portions characteristic of these metals. Doubtless, in absorbing their characteristic vibrations, these metals are further heated and expanded, and gradually lifted from the surface of the sun ; and the vibrations of light and heat that pass through them and escape are probably all ulti- mately absorbed in the same or some similar way in the dif- fused materials of space. The speculations of the elder Struve on the extinction of light in its passage through space — con- clusions founded on Sir William Herschel's observations of the Milky-Way — afford a happy and independent confirmation of these views. Moreover, the spectroscopic analyses of the light of the stars show broad dark bands, indicative of great extinctions of light. And we may add, that many gases and vapors which are transparent to luminous rays are found to absorb the obscure rays of heat. Such is the kind of evidence we have of what becomes of the light and heat, and a portion, at least, of the material of the sun. The heat which is not expended immediately in vapor- izing these materials is ultimately extinguished in further heat- A PHYSICAL THEORY OF THE UNIVERSE. 25 ing, expanding, and thus lifting the materials (may we not be- lieve ?) which have already been partially raised to the height, whence perhaps, in former ages, they in their turn were rained down as meteors upon the sun. In these suppositions we have exactly reversed the nebular hypothesis. Instead of, in former ages, a huge gaseous globe contracted by cooling and by gravi- tation, and consolidated at its centre, we have supposed one now existing, and filling that portion of the interstellar spaces over which the sun's attraction predominates, — a highly rarefied continuous gaseous mass, constantly evaporated and expanded from its solid centre, but constantly condensed and consoli- dated near its outer limits, — constantly heated at its centre by the fall of solid bodies from its outer limits, and constantly cooled and condensed at these limits by the conversion of heat into motion and the arrest of this motion by gravitation. There are certain chemical objections which apply equally to the views here advanced and to the nebular hypothesis. But these must necessarily arise from the limits' to the knowl- edge we can gain of the whole range of chemical phenomena. For what takes place in the chemist's laboratory, under the very limited conditions of temperature and pressure he can command, ought not to be regarded as determining the possi- bilities, or even the probabilities, of that cosmical chemistry of which we can hardly be supposed to know even the rudiments. We shall consider this subject, however, more particularly, after attending to what is now of more immediate interest, namely, the secondary mechanical conditions and phenomena that result from the suppositions we have made ; and particu- larly the question, how the systems of the planets and their satellites stand related to the round of changes we have con- sidered. The fundamental and most important motions of the solar system are, as we suppose, the radial movements of solid bodies inward and of gaseous bodies outward, arising from the coun- teractions of gravitation and heat. But these radial move- ments must assume a vortical form, if one does not already exist, such as is constantly exhibited by movements in the air and in water. The rotation of the sun, imparted to the mate- 2 26 PHILOSOPHICAL DISCUSSIONS. rials which rise in vapor from its surface, continues in them as they rise higher and higher, and though exhibited in a con- stantly diminishing tangential motion, remains in reality con- stant, as measured by what mechanicians term "rotation area." Or, rather, it is slowly increased by the mutual resistances of contiguous strata in the expanding gases, so that when this matter falls again towards the sun in the form of solid bodies, it falls in spiral trajectories, and only reaches the sun after perhaps many revolutions, or not at all, unless its motions be rapidly diminished by the resisting medium. If the resistance of the medium is not sufficient to convert the path of a falling meteor into a spiral, the meteor will mount again, and con- tinue to move perhaps for a long time in an eccentric orbit, like a comet. When, however, the meteor at, length, in any way, reaches the sun, a part of its motion is expended in in- creasing the sun's rotation, and thus compensating the loss of motion continually sustained by the sun in the evaporation of its material. The denser the resisting medium is in any system, the greater will be the revolution of its outer parts, and the larger will be the spiral trajectories which its falling bodies will describe. Such spiral or vortical motions as would thus be produced, or rather sustained, in the matter surround- ing the sun, is exhibited by the most powerful telescopes, in the forms of the appendages to certain nebulous stars, and in the structure of the so-called Spiral Nebulae. Perhaps the bodies which are supposed to give rise to the appearance of the zodiacal light would exhibit some such spiral arrangement, if seen from a point far above or below the ecliptic. It follows from this vortical motion, that the form which the diffused materials of the solar system would assume, or rather maintain, would be that of an oblate ellipsoid or of a flattened lenticular body. The height to which the matter would rise in the plane of the sun's equator before its massive and molec- ular motions would be arrested by gravitation, would be much greater than in the directions of the sun's axis of rotation. The degree of oblateness which such a system of diffused mat- ter will maintain depends on the frictions or resistances that successive strata exert on each other. It should be borne in A PHYSICAL THEORY OF THE UNIVERSE. 27 mind in this connection that friction is not a loss of force, where all kinds of force are taken into account. Friction or resistance can only effect a conversion of massive into molecu- lar motions, or the motion of velocity into the motion of heat. Hence, whatever velocity is lost by interior strata in the gase- ous materials of the solar system, and is not gained by those exterior to them, must yet be ultimately restored; for the sta- bility of such a system is no longer a question ■ this is insured in the fundamental mechanical law on which our speculations are founded. It may still be a question, however, whether the planetary bodies of such a system are successively produced and de- stroyed, like generations of animals and plants, or whether they are permanent elements- in a system of balanced forces and operations. So far as the effects of mutual perturbation are concerned, and independently of a resisting medium, as- tronomers have shown that the latter supposition is the more probable one ; but there are several other considerations which point to a different conclusion. In the first place, the consid- erations already mentioned. The existence of systematic rela- tions in the structure of the solar system, some of which are independent of its stability under the law of gravity, indicate the operations of causes other than the simple ones on which this stability depends, — such causes as the nebular hypothesis endeavored to define, but which we, in rejecting this hypothe- sis, have still to search for. It has undoubtedly occurred to our readers to ask how the planets stand related to the meteoric system, and in what man- ner, if at all, their motions and masses are affected by this per- petual shower of matter. As out of every two thousand million parts of the light and heat of the sun's radiation the earth receives one part, so out of the two thousand million meteors sent back in return the earth will receive one, or per- haps a somewhat larger- proportion, since the meteors are sup- posed to fall most thickly near the plane of the sun's equator. If we multiply this proportion by ten, as we probably may, it is still a very small quantity; but if we are permitted to multi- ply it by a factor of time as great as we please, this in.signifi- 28 PHILOSOPHICAL DISCUSSIONS. cance will disappear, and in its place we shall have a cosmical cause of the greatest moment in the history of the solar sys- tem. Two hundred million years is but a day in the cosmical eras, yet in that time the earth could receive as many bodies as fall to the sun in a year, or a hundredth part of the mass of the earth itself. In a hundred such days, then, the earth might be built up by the aggregation of meteors, provided it should lose none of the material thus collected, as the sun probably does. But this calculation proceeds on die supposi- tion that the earth would have caught as many meteors when it was smaller, as it probably does now. A correction is there- fore required which lengthens the period to three hundred such days, or to about a cosmical year, if we may so estimate times which are without limits or measure. In sixty thousand mil- lion years, then, the earth could have been made by the ag- gregation of meteors.* In this time the sun itself would have received and evaporated fifteen hundred times the amount of its present mass, provided a permanent amount of matter and heat should have been maintained in it during so long a period. In these estimates no account is taken of the heat immedi- ately absorbed in evaporation, or absorbed in the space in- cluded within the earth's orbit. This heat would probably require a still greater expenditure of motion, and the fall of a still greater number of bodies. Hence the period required to build up the earth's mass might be materially shortened. Such a method of inquiry, however, violates the canon we have laid down for our guidance in physical speculation. We must not suppose any action in nature to which there is not some counteraction, and no mode of production, however slow, from which in infinite time there could result an infinite * Most of the materials which fall to the earth are probably in the form of very small bodies, which must be disintegrated by heat in their passage through the atmosphere, and must consequently reach the earth's surface in the form of fine dust. At the rate of accumulation estimated above, this dust, when reduced to the mean density of the earth's materials, would add one foot to the thickness of its crust in about three thousand years. In the loose form of dust or mud this accumulation would amount to about a hundredth of an inch in a year. The materials which have accumulated within histor- ical periods over the ruins of ancient cities may thus in great part have been collected from the sky. The agencies of the winds and of flowing water in transporting and de- positing the loose materials of the earth's surface would distribute this star-dust in de- posits at the bottom of the sea, and in hills and mounds on the land. A PHYSICAL THEORY OF THE UNIVERSE. 29 product. We must, therefore, conclude that the planets either ultimately fall into the sun, and make a restitution of their peculations, or that heat and gravitation preserve in them also the balance of nature and the golden mean of virtue. The existence of a resisting medium favors the first supposition, unless it can be rendered probable that this medium revolves with velocities equal to those of the planets at the same dis- tances from the sun. There is also another cause affecting the mean distances of the planets. An increase of mass in the sun will diminish the size of the planetary orbits, and con- versely a diminution of this mass will increase the size of these orbits. The rate of change in the mass of the sun, whether to increase or to decrease, must depend on the relative rates of cooling by radiation and by evaporation. As the sun grows cooler by excessive radiation, its mass must be increased by the fall of meteors, and the planets will draw nearer to the sun ; but if its radiation be diminished, and a larger proportion of the heat be expended in evaporation, then the planets will withdraw from the sun. Such are the causes which may affect the mean distances of the planets. If on such grounds we may adopt the first of our supposi- tions, that the planets are successively formed and finally lost in the sun, like the meteors, the most probable hypothesis we can make concerning their origin is, that they are formed by the aggregation of meteors. Certain conditions, which, in the present state of our knowledge, it would perhaps be impossible to define, must determine the distances from the sun where these aggregations will begin ; but the body and the attraction of the planet, when once begun, will determine further aggre- gation until the planet either falls into the sun, or approaches to such a distance that the evaporation of its material keeps pace with the fall of matter Upon it. The size to which a planet could attain would thus be determined by the distance from the sun at which it begins to grow. A nearly circular orbit, and a small inclination of its plane to the plane of the sun's equator, would result from the circumstances attending the fall of the meteors, — their approach to the sun from every 3° PHILOSOPHICAL DISCUSSIONS. direction near the plane of the sun's equator.* A vortical motion and a rotation of the planet might result from such aggregations, which would be analogous to those of the sun and the general system. A more rigorous and comprehensive discussion of such problems than has yet been attempted is required before trustworthy conclusions can be formed. The following considerations may materially affect the con- clusions we have drawn from the existence of a resisting me- dium. The gaseous medium of the solar system might receive from the sun's rotation, and by the mutual friction of its own materials, greater velocities in its interior parts than the planets could have at the same distances from the sun, provided the exterior parts should move with less than planetary velocities, and should press with a portion of their weight upon the parts below them. For the centrifugal forces of the interior parts might thus be balanced, not merely by their own gravitation, but by a portion also of the weight of the superincumbent masses. At a distance from the sun less than half the mean distance of the planet Mercury, a period of revolution equal to that of the sun would produce a planetary velocity. At a greater distance, the medium might revolve more rapidly than the planets. But there must be a limit where the revolutions would be simply self-sustaining, and beyond this the medium would move less rapidly than the planets. So far, therefore, as a resisting medium could affect the motions of the planetary bodies, it might tend to increase the dimensions of the interior orbits, and to diminish those of the exterior ones; and it would thus tend to concentrate the planets, not in the sun, but at this limiting distance, where the medium would neither accelerate nor retard their motions. The motions of the medium would produce the greatest effect upon the smaller bodies of the solar system, which would, therefore, approach most rapidly to this limiting distance. That region in the solar system, about half the distance from the sun to the orbit of Jupiter, which is so thickly crowded with small planetary bodies or asteroids, may * The rare occurrence of spots on the sun beyond thirty degrees either side of its equator may indicate some connection between these spots and the fall of meteors and serve to determine the limits of the meteoric system. A PHYSICAL THEORY OF THE UNIVERSE. 31 be regarded, on this hypothesis, as the region in which the gaseous medium now revolves with planetary velocity. Could this limiting distance remain fixed for a very long period, most of the planetary masses of the solar system might accumulate there, and be concentrated into one huge planet or secondary sun, and the solar system would thus be converted into a binary system, like those observed among the stars. But from the small amount of matter probably contained in the asteroid system; we ought to conclude that this limiting distance changes from time to time, as the medium grows denser or rarer. The planets are not the only aggregations of meteoric bodies which we have to account for. Besides the comets, there are probably streams of meteors falling to or circulating around the sun. This is rendered very probable by the phenomena of the showers of these bodies which fall into our atmosphere at certain seasons of the year, or at certain positions in the earth's orbit.* And further, the rings of Saturn are probably examples of the same kind of meteoric aggregation. For of the three hypotheses in regard to the constitution of these rings which have been submitted to rigorous mathematical examination. — namely, first, that they are solid, secondly, that they are fluid, and, thirdly, that they are composed of distinct bodies or me- teors, — the latter is the only one which has been found to afford the conditions of stability which are implied in their continued existence. It is unnecessary to add the physical reasons which render this hypothesis still more probable. We have no space to consider the many interesting geological * There is a period of about eleven years in the numbers of spots that appear on the surface of the sun, a period coincident with that of the amount of diurnal variations in terrestrial magnetism, — an amount undoubtedly due to the influence of the sun. This period also coincides nearly with the period of the revolution of Jupiter, the largest planet in our system. If, then* we may suppose that the sun's spots are occasioned by the fall of large meteors, the courses of which lie near to the orbit of Jupiter, the attrac- tions of this planet, alternately turning such a stream of bodies upon and away from the surface of the sun, would connect these three nearly coincident periods by a common physical cause The phenomena of magnetism and electricity, as subordinate manifestations of motion and conditions of motion, have not been included in our speculations on the commuta- tions of "power," on account of their insignificant values as compared with the three principal forms of "power." For the same reason, we omit any consideration of the numerous but minute modifications of "power" which are manifested by the forces of vital phenomena on the surface of the earth. 32 PHIL OSOPHICA L DISC USSIONS. consequences which follow from our hypothesis. Let it suffice to remark, that the formation of the earth's mass by meteoric aggregation precludes the hypothesis, otherwise improbable, that the core of the earth is a molten mass. The occurrence of volcanoes in local systems, distinct from each other, points to local causes of an unknown chemical character as the true sources of these phenomena. The heterogeneous character of the materials of the earth's crust, in which are mingled, in the most intimate manner, all kinds of substances, irrespectively of their chemical affinities, and in opposition to their chemical forces of aggression, could hardly be the results of the actions of heat and aqueous solution, both of which afford conditions favorable to chemical aggregation. Indeed, in most cases in which such aggregation occurs, where homogeneous and chem- ically simple substances are found in considerable quantities, the agency either of heat or aqueous solution is evident. It is hardly necessary to add, that the theory of meteoric aggregation is the one which would most readily explain these facts. But we must here leave the consideration of these interest- ing problems, and return to a topic much more obscure, to which we called attention a few pages back. The dynamical theory of heat has not only suggested new and interesting inquiries concerning the constitution of the universe, but it throws new light in the philosophy of chemical phenomena on such problems as the origin of the three states of aggregation in matter, and on the character of the changes which may take place under circumstances beyond the reach of chemical experiments and observation. That the dreams of the alchemists were at fault rather in point of method than of doctrine, is a confession which the modern chemist must make, when he compares the slight re- sources of experiment at his command with the possibilities of nature. If, as has been surmised, the characteristic properties of different kinds of matter consist in characteristic internal or molecular motions (and molecular conditions of motion), a complete destruction of such motions would obliterate all the characteristic differences of matter, and such a result might be attained by the production of absolute cold. In respect to A PHYSICAL THEORY OF THE UNIVERSE. 33 the motions of light and heat, however, the universe, so far as we know it, and even so far as we could know it, is a perfectly continuous body. In no corner or recess of its unfathomable depths to which the feeblest light of a single star could find its way, can there be an absence of the motions of light and heat. Nothing can set bounds to the all-pervading reach of these mo- tions except limits to that medium of motion, the luminiferous ether; and these, so far as all cognizable physical conditions are concerned, would be limits to space itself. That potent sidereal influence, the absolute cold, transmuting all substances into one, could only arise momentarily, in nodal points or lines or surfaces, but could not be extended discontinuously into space of three dimensions. What may happen at such times and limits, where matter, expiring from one form of chemical life, may be awakened to another, according to the kind of molecular agitation which may next overtake it, and deter- mine its history, perhaps for myriads of years, is what the chemist cannot tell us, and only the alchemist can dream. It suffices for our instruction, that the chemistry of absolute cold has possibilities of which experimental chemistry affords no criterion, and may play a part in the economy of nature not inferior to that of gravitation or heat. But it may be objected, on grounds of experimental chem- istry, "that the sun's heat, though sufficient to volatize the least fusible materials, could not keep them in the form of vapor at the heights and in the temperature of the interplan- etary spaces, much less lift them in the form of vapor to the heights of the interstellar regions whence the meteors are sup- posed to fall. For most bodies which are solid at ordinary ter- restrial temperatures tend, upon cooling, to crystallize with such energy that they would soon be precipitated from the vaporous form." But this objection takes no account of those effects of diffusion, expansion, and commingling of heterogene- ous materials, which must remove the parts of a volatilized body to such hopeless distances from each other that the forces of chemical aggregation might require ages to collect what is thus dispersed. Nor can any account be taken of such un- known laws of chemical affinity and aggregation as are possible 34 PHILOSOPHICAL DISCUSSIONS. under the circumstances we are considering. The known laws of chemical action should, then, be ranked with those laws- of life, exhibited in the phenomena of growth, which were too hastily generalized and applied, in "the theory of evolution," to the interpretation of the riddles and the explication of the order of the System of the Worlrl , NATURAL THEOLOGY AS A POSITIVE SCIENCE* Natural history and anatomy have hitherto furnished the principal grounds to the theologian for the speculation of final causes, since these sciences exhibit many instances of a com- plex combination of causes in the structures and habits of or- ganic bodies, and at the same time a distinct and peculiar class of effects, namely, those which constitute the well-being and perfection of organic life; and from these causes and effects, regarded as means and ends in the order of nature, the argu- ments and illustrations of natural theology have been chiefly drawn. The facts of these sciences are not merely the most useful to the theologian ; they are indeed indispensable, and occupy a peculiar position in his argument, since they alone afford the class of effects on which, assumed as ends, the spec- ulation of final causes ultimately rests. It is only by assuming human welfare, or with this the wel- fare also of other sentient beings, as the end for which the uni- verse exists, that the doctrine of final causes has hitherto found any support in natural science. Though it is still maintained by theologians that the argu- ments for design are properly inductive arguments, yet the physical proofs of natural theology are not regarded by many modern writers as having any independent weight; and it is in mental and moral science that the facts are sought which will warrant the induction of design from the general phenom- ena of nature. It is hardly considered logical, even by the theological writers of our day, to conclude, with Paley, "that * From the North American Review, for January, 1865. 36 PHILOSOPHICAL DISCUSSIONS. the works of nature proceed from intelligence and design ; be- cause, in the properties of relation to a purpose, subserviency to a use, they resemble what intelligence and design are con- stantly producing, and what nothing [which we know] except intelligence and design ever produce at all." For it is denied by the physical philosopher that causes and effects in natural phenomena can be interpreted into the terms of natural theol- ogy by any key which science itself affords. By what crite- rion, he would ask, can we distinguish among the numberless effects, that are also causes, and among the causes that may, for aught we can know, be also effects, — how can we distin- guish which are the means and which are the ends ? What effects are we warranted by observation in calling final, or final causes, or the ends for which the others exist ? The belief on other grounds that there are final causes, that the universe exists for some purpose, is one thing ; but the belief that sci- ence discloses, or even that science can disclose, what this purpose is, is quite a different thing. The designation of those effects as final in nature which contribute to human desires or human welfare, or even to the welfare of all sentient beings, cannot be legitimately made for the purpose of this argument, since human and other sentient beings are not the agents by which these supposed ends are attained; neither can the causes which bring these effects to pass be regarded as ser- vants obedient to the commands of the agents to whom these effects are desirable. The analogy of natural production to human contrivance fails them at the very outset; and the in- terpretation of natural causes and effects as means and ends, virtually assumes the conclusion of the argument, and is not founded on any natural evidence. These considerations are overlooked by most writers on this subject, who, in addition to a legitimate faith in final causes, assume the dogma that these causes are manifest or discoverable. They begin with the definition, sometimes called an argument, "that a combi- nation of means conspiring to a particular end implies intelli- gence," and they then assume that the causes which science discovers are means, or exist for the sake of the effects which science accounts for; and from the relation of means to ends, thus assumed, they infer intelligence. NATURAL THEOLOGY AS A POSLTIVE SCIENCE. 37 The definition we have quoted contains, however, more than is really implied in this argument, since the relation of means to ends in itself, and without further qualification, im- plies intelligence, while a combination of means conspiring to a particular end implies a high degree of intelligence ; and it is with this, the degree of intelligence manifested in the phe- nomena of nature, that scientific discourses on the natural evi- dences are really dealing, though sometimes unconsciously. These discourses really aim, not so much to prove the exist- ence of design in the universe, as to show the wisdom of cer- tain designs which are assumed to be manifest. But for this purpose it is requisite to translate the facts of science, and those combinations of causes which are discovered to be the conditions of particular effects, into the terms of the argument, and to show that these combinations are means, or exist for the sake of particular effects, for which, as ends, the universe itself must be shown to exist, — a task for which science is ob- viously incompetent. Waiving these fundamental objections to the argument for design, which, let us repeat, are not objections to the spiritual doctrine of final causes, or to the belief that final causes exist, we will turn to the objections which modern writers of natu- ral theology themselves allow. It is essential to the validity of Paley's argument, that " de- sign," or the determination of effects by the intelligence of an agent, be shown to be not merely the only known cause of such effects, but also to be a real cause, or an independent de- termination by an efficient agent. If intelligence itself be a product, if the human powers of contrivance are themselves effects, it follows that designed effects should be ascribed, not to intelligence, but to the causes of intelligence ; and the same objection will hold against the theologian's use of the word "design," which he urges against the physicist's use of the word "law." "It is a perversion of language," says Paley, "to assign any law as the efficient operative cause of anything. A law presupposes an agent, for it only is the mode according to which the agent proceeds ; it implies a power, for it is the order according to which this power acts. Without this agent, 38 PHILOSOPHICAL DISCUSSIONS. without this power, which are both distinct from itself, the 'law' does nothing, is nothing." By substituting the word "design" for the word "law" in this quotation, we have the materialist's objection to the theologian's perversion of lan- guage. This objection was entirely overlooked by Paley, who seems to have thought it sufficient for the purposes of his ar- gument to consider only the. phenomena of the visible material universe. But later writers have seen the necessity of basing the argument for design on the psychological doctrine that in- telligence is a free, undetermined power, and that design is the free, undetermined act of this power. Without this assump- tion, which indeed Paley himself virtually makes, it would be as unphilosophical to refer the course of nature to the deter- mination of intelligence, as it is to refer it to the determination of the abstraction which the materialist prefers, or to the "agency of law." " That intelligence stands first in the absolute order of exist- ence, — in other words, that final preceded efficient causes, — and that the universe is governed by moral laws," are the two propositions, the proof of which, says Sir William Hamilton, is the proof of a God; and this proof "establishes its founda- tion exclusively on the phenomena of mind." Without this psychological proof, the order of adaptation cannot be logically referred to the order of design ; and the resemblance of human contrivances to the adaptations of nature can only warrant the conclusion that both proceed from similar conditions, and by a power of whose efficiency human intelligence and phys- ical laws are alike manifestations, but whose nature neither hu- man intelligence comprehends nor physical laws can disclose. Even such a result, which is all that the unaided physical sciences can compass, is not altogether barren of religious in- terest, though it is made so by the materialist's attempt to de- fine the nature of power by assigning to physical forces an absolute efficiency. The spiritualist, on the other hand, if we allow his psychological proof that intelligence stands first in the absolute order of existence, and is a free, undetermined power, is logically competent to interpret the order of nature as a designed order. Yet to him physical proofs of design NATURAL THEOLOGY AS A POSITIVE SCIENCE. 39 have little or no value, and can only serve as obscure and enigmatical illustrations of what is far more clearly apparent in the study of mind. And though logically competent to inter- pret the order of design, if his spiritual doctrine be true, yet the difficulties which we first mentioned, and waived for the nonce, are difficulties as insuperable to the psychologist as to the physicist. He gains no criterion from his studies by which to distinguish, in the order of natural phenomena, which are the means and which are the ends, or where the relation of means to ends is to be found, among the infinite successions of effects which are also causes, and of causes which may, for aught he can know, be also effects. His faith in final causes is not a guide by which he can determine what the final causes are by which he believes the order of nature to be determined. These theoretical objections to a philosophy, which assigns physical reasons for a faith in final causes, are by no means the most important objections. The practical influences and effects of such philosophizing are, we believe, more obnoxious to the true interests of religion than its methods are to the true principles of philosophy, and fully justify an examination of its arguments. For bad arguments may go for nothing, while good ones necessitate their conclusions • and we think it fortunate for the purity of religious truth that theologians have succeeded no better in this direction. Not only do the peculiar doctrines of natural theology add nothing to the grounds of a faith in final causes ; they, in effect, narrow this faith to ideas which scarcely rise in dignity above the rank of superstitions. If to believe that God is what we can think him to be is blasphemy, what shall we call the at- tempt to discover his intentions and to interpret his plans in nature ? If science were able to discover a much closer anal- ogy than it does between the adaptations of nature and the designs of human contrivance, would it be any less derogatory to the dignity of the Divine nature to attempt by such analo- gies to fathom his designs and plans, or to suppose that what appears as a designed order is really any clew to the purposes of the Almighty ? And when, even transcending this degree of presumption, theology would fix a limit to the researches and 40 PHILOSOPHICAL DISCUSSIONS. hypotheses of science, on the ground that they tend to subvert religious doctrines, or the assumed results of a religious phi- losophy, we are warranted — nay, constrained, from practical considerations — to question the grounds of its pretensions, to allow it no longer to shield its falseness and weakness behind the dignity and worth of the interests to which it is falsely dedicated. It is from the illegitimate pretensions of natural theology that the figment of a conflict between science and re- ligion has arisen ; and the efforts of religious thinkers to coun- teract the supposed atheistical tendencies of science, and to give a religious interpretation to its facts, have only served to deepen the false impression that such a conflict actually ex- ists, so that revolutions in scientific theories have been made to appear in the character of refutations of religious doctrines. That there is a fundamental distinction between the natures of scientific and religious ideas ought never to be doubted ; but that contradiction can arise, except between religious and superstitious ideas, ought not for a moment to be admitted. Progress in science is really a progress in religious truth, not because any new reasons are discovered for the doctrines of religion, but because advancement in knowledge frees us from the errors both of ignorance and of superstition, exposing the mistakes of a false religious philosophy, as well as those of a false science. If the teachings of natural theology are liable to be refuted or corrected by progress in knowledge, it is legit- imate to suppose, not that science is irreligious, but that these teachings are superstitious ; and whatever evils result from the discoveries of science are attributable to the rashness of the theo- logian, and not to the supposed irreligious tendencies of science. When a proof of special design is invalidated by the discovery that a particular effect in the operations of nature, which pre- viously appeared to result from a special constitution and ad- justment of certain forces, is really a consequent of the general properties of matter, — when, for example, the laws of plan- etary motion were shown to result from the law of universal gravitation, and the mathematical plan of the solar system was seen to be a consequent of a single universal principle, — the harm, if there be any, results from the theologian's mistakes, NATURAL THEOLOGY AS A POSLTLVE SCLENCE. 4I and not from the corrections of science. He should refrain from attributing any special plan or purpose to the creation, if he would find in science a constant support to religious truth. But this abstinence does not involve a withdrawal of the mind from the proper religious interests of natural science, nor weaken a legitimate faith in final causes. Even the New- tonian mechanism of the heavens, simple, primordial, and necessary as it seems, still discloses to the devout mind evi- dence of a wisdom unfathomable, and of a design which tran- scends interpretation • and when, in the more complicated order of organic, life, surprising and beautiful adaptations inspire in the naturalist the conviction that purpose and intelligence are manifested in them, — that they spring from a nature akin to the devising power of his own mind, — there is nothing in science or philosophy which can legitimately rebuke his enthusiasm, — nothing, unless it be the dogmatism which would presumptu- ously interpret as science what is only manifest to faith, or would require of faith that it shall justify itself by proofs. The progress of science has indeed been a progress in relig- ious truth, but in spite of false theology, and in a way which narrow theologians have constantly opposed. It has denned with greater and greater distinctness the boundary between what can be discovered and what cannot. It has purified re- ligious truth by turning back the moral consciousness to dis- cover clearly in itself what it had obscurely divined from its own interpretations of nature. It has impressed on the mind of the cautious inquirer the futility, as well as the irreverence, of attempting a philosophy which can at best be but a finer sort of superstition, a real limitation to our conceptions of final causes, while apparently an extension of them. But instead of learning these lessons from the experience of repeated failures, theologians have constantly opposed new hypotheses in science, until proof has compelled a tardy assent, and even then they have retreated to other regions of science, as if these were the only refuge of a persecuted faith. Humility and cautiousness, and that suspension of judgment in matters about which we really know so little, which a recent theological writer has recommended, in view of the pending 42 PHILOSOPHICAL DISCUSSIONS. controversy on the origin of organic species and adaptations, are virtues, which, had they been generally cultivated by theo- logians, would have rendered this controversy harmless at least, if not unnecessary. THE PHILOSOPHY OF HERBERT SPENCER* Why the inductive and mathematical sciences, after their first rapid development at the culmination of Greek civiliza- tion, advanced so slowly for two thousand years, — and why in the following two hundred years a knowledge of natural and mathematical science has accumulated, which so vastly exceeds all that was previously known that these sciences may be justly regarded as the products of our own times, — are questions which have interested the modern philosopher not less than the objects with which these sciences are more immediately conversant. Was it in the employment of a new method of research, or in the exercise of greater virtue in the use of old methods, that this singular modern phenomenon had its ori- gin ? Was the long period one of arrested development, and is the modern era one of a normal growth ? or should we as- cribe the characteristics of both periods to so-called historical accidents, — to the influence of conjunctions in circumstances of which no explanation is possible, save in the omnipotence and wisdom of a guiding Providence ? The explanation which has become commonplace, that the ancients employed deduction chiefly in their scientific inqui- ries, while the moderns employ induction, proves to be too narrow, and fails upon close examination to point with suffi- cient distinctness the contrast that is evident between ancient and modern scientific doctrines and inquiries. For all knowl- edge is founded on observation, and proceeds from this by anal- ysis and synthesis, by synthesis and analysis, by induction and deduction, and if possible by verification, or by new appeals to * From the North American Review, April, 1S65. 44 PHILOSOPHICAL DISCUSSIONS. observation under the guidance of deduction, — by steps which are indeed correlative parts of one method ; and the ancient sciences afford examples of every one of these methods, or parts of the one complete method, which have been generalized from the examples of science. A failure to employ or to employ adequately any one of these partial methods, an imperfection in the arts and re- sources of observation and experiment, carelessness in observa- tion, neglect of relevant facts, vagueness and carelessness in reasoning, and the failure to draw the consequences of theory and test them by appeal to experiment and observation, — these are the faults which cause all failures to ascertain truth, whether among the ancients or the moderns ; but this statement does not explain why the modern is possessed of a greater virtue, and by what means he attained to his superiority. Much less does it explain the sudden growth of science in recent times. The attempt to discover the explanation of this phenome- non in the antithesis of "facts" and "theories" or "facts" and "ideas," — in the neglect among the ancients of the former, and •their too exclusive attention to the latter, — proves also to be too narrow, as well as open to the charge of vagueness. For, in the first place, the antithesis is not complete. Facts and the- ories are not co-ordinate species. Theories, if true, are facts, — a particular class of facts indeed, generally complex ones, but still facts. Facts, on the other hand, even in the narrowest signification of the word, if they be at all complex, and if a logical connection subsists between their constituents, have all the positive attributes of theories. Nevertheless, this distinction, however inadequate it may be to explain the source of true method in science, is well found- ed, and connotes an important character in true method. A fact is a proposition of which the verification by an appeal to the primary sources of our knowledge or to experience is direct and simple. A theory, on the other hand, if true, has all the characteristics of a fact, except that its verification is possible only by indirect, remote, and difficult means. To con- vert theories into facts is to add simple verification, and the THE PHILOSOPHY OF HERBERT SPENCER. 45 theory thus acquires the full characteristics of a fact. When Pascal caused the Torricellian tube to be carried up the Puy de Dome, and thus showed that the mercurial column was sus- tained by the weight of the atmosphere, he brought the theory of atmospheric pressure nearly down to the level of a fact of observation. But even in this most remarkable instance of sci- entific discovery theory was not wholly reduced to fact, since the verification, though easy, was not entirely simple, and was incomplete until further observations showed that the quantity of the fall in the Torricellian tube agreed with deductions from the combined theories of atmospherical pressure and elasticity. In the same way the theory of universal gravitation fails to be- come a fact in the proper sense of this word, however complete its verification, because this verification is not simple and direct, or through the immediate activity of our perceptive powers. Modern science deals then no less with theories than with facts, but always as much as possible with the verification of theories, — if not to make them facts by simple verification through experiment and observation, at least to prove their truth by indirect verification. The distinction of fact and theory thus yields an important principle, of which M. Comte and his followers have made much account. It is in the employment of verification, they say, and in the possibility of it, that the superiority of modern inductive research consists ; and it is because the ancients did not, or could not, verify their theories, that they made such insignificant progress in science. It is indisputable that verifi- cation is essential to the completeness of scientific method ; but there is still room for debate as to what constitutes verification in the various departments of philosophical inquiry. So long as the philosophy of method fails to give a complete inventory of our primary sources of knowledge, and cannot decide au- thoritatively what are the origins of first truths, or the truths of observation, so long will it remain uncertain what is a legiti- mate appeal to observation, or what is a real verification. The Platonists or the rationalists may equally with the empiricists claim verification for their theories ; for do they not appeal to the reason for confirmation of deductions from their theories, 46 PHILOSOPHICAL DISCUSSIONS, which they regard as founded on observation of what the rea- son reveals to them ? The positivists' principle of verification comes, then, only to this, — that, inasmuch as mankind are nearly unanimous about the testimony and trustworthiness of their senses, but are di- vided about the validity of all other kinds of authority, which they in a word call the reason, or internal sense, therefore verifi- cation by the senses produces absolute conviction, while verifi- cation by the reason settles nothing, but is liable to the same uncertainty which attends the primary appeals to this authority for the data of speculative knowledge. But not only does the so-called metaphysical philosophy em- ploy a species of verification by appealing to the testimony of reason, consciousness, or internal sense ; but the ancient phys- ical sciences afford examples of the confirmation of theory by observation proper. The Ptolemaic system of astronomy was an instance of the employment of every one of the partial steps of true method; and the theory of epicycles not only sought to represent the facts of observation, but also by the prediction of astronomical phenomena to verify the truth of its representa- tion. Modern astronomy does not proceed otherwise, except that its theories represent a much greater number of facts of observation, and are confirmed by much more efficient experi- mental tests. The difference, then, between ancient and modern science is not truly characterized by any of the several explanations which have been proposed. The explanation, however, which, in our opinion, comes nearest to the true solution, and yet fails to des- ignate the real point of difference, is that which the positivists find in the distinction between "objective method" and "sub- jective method." The objective method is verification by sensuous tests, tests of sensible experience, — a deduction from theory of consequences, of which we may have sensible experi- ences if they be true. The subjective method, on the other hand, appeals to the tests of internal evidence, tests of reason, and the data of self-consciousness. But whatever be the origin of the theories of science, whether from a systematic examina- tion of empirical facts by conscious induction, or from the THE PHILOSOPHY OF HERBERT SPENCER. 47 natural biases of the mind, the so-called intuitions of reason, in other words what seems probable without a distinct survey of our experiences, — whatever the origin, real or ideal, the value of these theories can only be tested, say the positivists, by an appeal to sensible experience, by deductions from them of con- sequences which we can confirm by the undoubted testimony of the senses. Thus, while ideal or transcendental elements are admitted into scientific researches, though in themselves insusceptible of simple verification, they must still show creden- tials from the senses, either by affording from themselves con- sequences capable of sensuous verification, or by yielding such consequences in conjunction with ideas which by themselves are verifiable. It is undoubtedly true, that one of the leading traits of modern scientific research is this reduction of ideas to the tests of experience. The systematic development of ideas through induction from the first and simplest facts of observation, is by no means so obvious a characteristic. Inductions are still per- formed for the most part unconsciously and unsystematically. Ideas are developed by the sagacity of the expert, rather than by the systematic procedures of the philosopher. But when and however ideas are developed science cares nothing, for it is only by subsequent tests of sensible experience that ideas are admitted into the pandects of science. It is of no consequence to scientific astronomy whence the theory of gravitation arose; whether as an induction from the theories of attractions and the law of radiations, or from the rational simplicity of this law itself, as the most natural suppo- sition which could be made. Science asks no questions about the ontological pedigree or a priori character of a theory, but is content to judge it by its performance; and it is thus that a knowledge of nature, having all the certainty which the senses are competent to inspire, has been attained, — a knowledge which maintains a strict neutrality toward all philosophical systems, and concerns itself not at all with the genesis or a priori grounds of ideas. This mode of philosophizing is not, however, exclusively found in modern scientific research. Ptolemy claimed for his 48 PHILOSOPHICAL DISCUSSIONS.. epicycles only that "they saved the appearances;" and he- might have said, with as much propriety as Newton, "Hypothe- ses 11011 Jingo" for it was the aim of his research to represent abstractly, and by the most general formulas, the characteris- tics of the movements of the planets, — an aim which modern astronomy, with a much simpler hypothesis, and with immense- ly increased facilities, still pursues. We find, therefore, that while moderns follow a true method of investigation with greater facilities and greater fidelity than the ancients, and with a clearer apprehension of its elements and conditions, yet that no new discoveries in method have been made, and no general sources of truth have been pointed out, which were not patent and known to the ancients; and we. have so far failed to discover any solution to the problem with which we began. We have seen that it was not by the em- ployment of a new method of research, but in the exercise of greater virtue in the use of old methods, that modern scientific researches have succeeded. But whence this greater virtue ? What vivifying, energizing influence awakened the sixteenth century to the movement, which has continued down to the present day to engross, and even to create, the energies of philosophic thought in the study of natural phenomena? Ob- viously some interest was awakened, which had before been powerless, or had influenced only men of rare and extraordi- nary genius, or else some opposing interest had ceased to exer- cise a preponderating influence. We have now arrived at a new order of inquiries. We ask no longer what are the differences of method between ancient and modern scientific researches, but we seek the difference in the motives which actuated the philosophic inquiries of the two periods. We seek for the interests which in modern times have so powerfully drawn men of all orders of intelligence to the pursuit of science, and to an observance of the conditions requisite for its successful prosecution. We do not inquire what course has led to successful answers in science, but what motives have prompted the pertinent questions. In place of the positivists' phraseology, that the ancients followed "the subjective method," or appealed for the verifica : THE PHILOSOPHY OF HERBERT SPENCER. 49 tion of their theories to natural beliefs, while the modems fol- low "the objective method," or appeal to new and independent experimental evidence, — if. we substitute the word "motive" for "method," we have the terms of one of the conclusions on which we wish to insist. But these require explanation. By a subjective motive we mean one having its origin in natural universal human interests and emotions, which existecb before philosophy was born, which continue to exist in the maturity of philosophy, and determine the character of an important and by no means defunct order of human specula- tions. By an objective motive we mean one having an empir- ical origin, arising in the course of an inquiry; springing from interests which are defined by what we already know, and not by what we have always felt, — interests which depend on ac- quired knowledge, and not on natural desires and emotions. Among the latter we must include the natural desire for knowledge, or the primitive, undisciplined sentiment of curi- osity. This becomes an objective motive when it ceases to be associated with our fears, our respects, our aspirations, — our emotional nature; when it ceases to prompt questions as to w r hat relates to our personal destiny, our ambitions, our moral worth; when it ceases to have man, his personal and social nature, as its central and controlling objects. A curi- osity which is determined chiefly or solely by the felt imperfec- tions of knowledge as such, and without reference to the uses this knowledge may subserve, is prompted by what we call an objective motive. A spirit of inquiry which is freed from the influence of our active powers, and the interests that gave birth to theological and metaphysical philosophies, — which yields passively and easily to the direction of objective motives, to the felt imperfec- tions of knowledge as such, — is necessarily, at all times, a weak feeling; and before a body of systematic, well-digested, and well-ascertained scientific truth had been generated, could hardly have had any persistent influence on the direction of inquiry. The motives to theological and metaphysical speculation exist from the beginning of civilized human life in the active 3 5 o PHILOSOPHICAL DISCUSSIONS. emotional nature of man. Curiosity as a love of the marvel- ous, or as a love of facts, — new facts, prized because they are new and stimulating, — also dates back of civilized life. These motives find play in human nature, as it emerges from a semi- animal state; but they also persist and determine the growth of the human mind in its most advanced development. The questions of philosophy proper are human desires and fears and aspirations — human emotions — taking an intel- lectual form. Science follows, but does not supersede, this phi- losophy. The three phases which the positivists assign to the development of the human mind — the Theological, the Met- aphysical, and the Positive or Scientific — are not in reality successive, except in their beginnings. They co-exist in all the highest developments of civilization and mental activity. They, co-existed in the golden age of Greek civilization, in the in- tense mental activity of the Middle Ages. They move on to- gether in this marvelous modern era. But until this latest epoch positive science was always the inferior philosophy, — hardly a distinct philosophy at all, — not yet born. But at the beginning of the modern era its gestation was completed. A body of knowledge existed, sufficiently extensive, coherent, and varied, to bear within it a life of its own, — an independent life, — which was able to collect to itself, by its own determina- tions, the materials of a continued, new, and ever-increasing mental activity, — an activity determined solely by an objective curiosity, or by curiosity in its purest, fullest, and highest en- ergy. We are probably indebted to the few men of scientific genius who lived during the slow advancement of modern civilization for the foundation of this culture, — for the accumulation of the knowledge requisite for this subsequent growth. These men were doubtless, for the most part, the products of their own time and civilization, as indeed all great men have been, but still originators, by concentrating and making productive the energies, tendencies, and knowledges which, but for them, would have remained inert and unfruitful. It is to such men, born at long intervals in the slow progress of civilization, each carrying forward a little the work of his predecessor, that we THE PHILOSOPHY OF HERBERT SPENCER. 5I probably owe our modern science, rather than to the influence of any single mind, like Bacon, who was, like his predecessors, but the lens which collected the light of his times, — who prophesied rather than inaugurated the new era. And we owe science to the combined energies of individual men of genius, rather than to any tendency to progress inherent in civilization. We find, then, the explanation of the modern development of science in the accumulation of a body of certified knowl- edge, sufficiently extensive to engage and discipline a rational scientific curiosity, and stimulate it to act independently of other motives. It is doubtless true that other motives have influenced this development, and especially that motives of material utility have had a powerful effect in stimulating inquiry. Ancient schools of philosophy despised narrow material utilities, the servile arts, and sought no instruction in what moderns dignify by the name of useful arts; but modern science finds in the requirements of the material arts the safest guide to exact knowledge. A theory wbich is utilized receives the highest possible certificate of truth. Navigation by the aid of astronomical tables, the magnetic telegraph, the innumer- able utilities of mechanical and chemical science, are constant and perfect tests of scientific theories, and afford the standard of certitude, which science has been able to apply so exten- sively in its interpretations of natural phenomena. But the motives proper to science, though purified by their dissociation from the subjective determinations and tendencies, which gave an anthropomorphic and teleological character to ancient views of nature, are not the only legitimate motives to philosophical inquiry. There is another curiosity purified by its association with the nobler sentiments, — with wonder, ad- miration, veneration, — and with the interests of our moral and aesthetical natures. This curiosity is the motive to philosophy proper. "Wonder is a highly philosophical affection," says Plato's Socrates ; " indeed, there is no other principle of philos- ophy but this." Curiosity determined by natural sentiments and emotions — subjective curiosity — is the cause of a culture co-extensive with civilization, long preceding the growth of science, and constitut- 5 2 PHILOSOPHICAL DISCUSSIONS. ing all that is peculiar to civilized life except the material arts. However meanly the conclusions of theological and metaphys- ical speculations may appear, when tried by the objective stand- ard of science, they too have their superiorities, by the test of which science becomes in turn insignificant. Unverified con- clusions, vague ideas, crude fancies, they may be, but they cer- tainly are the products of activities which constitute more of human happiness and human worth than the narrow material standards of science have been able to measure. Philosophy proper should be classed with the Religions and with the Fine Arts, and estimated rather by the dignity of its motives, and the value it directs us to, than by the value of its own attainments. To condemn this pursuit because it fails to accomplish what science does, would be to condemn that which has formed in human nature habits, ideas, and associations on which all that is best in us depends, — would warrant the con- demnation of science itself, since science scarcely existed at all for two thousand years of civilization, and represented as a dis- tinct department during this period only the interests of the servile arts. The objects of Philosophy were those which the religious ideas and emotions of man presented to his specula- tive curiosity. These motives, though proper to Philosophy, also gave direction to inquiries in Physics and Astronomy. The Fine Arts sprang from the same interests, and persisted through the conservative power of religious interests in a de- velopment to which the modern world offers no parallel. We have no styles in Art, no persistently pursued efforts for per- fection in beauty, because we are not held to the conditions of this perfection by the religious motives which directed ancient Art. The growth of Theology and Metaphysics is less vigor- ous now for the same reason. Theology was Philosophy de- veloped in the interests of Religion or of religious feeling, and Metaphysics was cultivated in the interests of Theology. Both aimed at truth ; both were determined by the same love of sim- plicity and unity in knowledge, which determines all search after truth; but neither cared for simple truth alone. When pursued for the truth of fact alone, they both degenerate into affectation and emptiness. We do not omit the sceptical phi- THE PHILOSOPHY OF HERBERT SPENCER. 53 losophies of antiquity from this description, because they were not held independently of the religious interests of the orthodox philosophy, but in opposition to them or in criticism of them. Theology and Metaphysics failed to apply a correct method and to arrive at certain results, not because philosophers were ignorant of method, but because the object-matters of their re- search were not questions of sensible experience, — were not mere questions of facts of which the mind is the passive recip- ient through the senses. Their aim was to prove truth, not to discover it, — to reduce opinions and ideas which had the war- rant of religious associations to the simplicity and consistency of truth; and when ideas and opinions have this warrant, it does not require the verification of the senses to make the con- clusions of Philosophy acceptable and true to the religious in- stincts. To educe conclusions acceptable to these instincts and in opposition to no known truth, — in other words, to free relig- ious beliefs from contradictions and to give them consistency, — was the aspiration and the devoted service of Philosophy. Philosophy has in fact three phases instead of two. For as Theology was a speculation prosecuted in the interest of re- ligious feeling, and Metaphysics a speculation in defense or criticism of the doctrines of Theology, so Criticism or Critical Philosophy is an examination of metaphysical conclusions. But the latter is properly, in its motives, a scientific specula- tion. Such is the true logical order of Philosophy proper, though all these phases may and do co-exist in history. It is the opinion of many modern thinkers, besides the so- called Positivists, or avowed followers of M. Comte, that sci- ence, as we have defined it, or truth pursued simply in the in- terests of a rational curiosity, and for the mental discipline and the material utilities of its processes and conclusions, will here- after occupy more and more the attention of mankind, to the exclusion of the older philosophy. It is also the opinion of these thinkers, that this is not to be regretted, but rather wel- comed as a step forward in the advancement of human welfare and civilization ; that the pursuit of science and its utilities is capable of inspiring as great and earnest a devotion as those which religious interests have inspired, and which have hitherto 54 PHILOSOPHICAL DISCUSSIONS. determined the destinies of mankind and given form to human thought, and one vastly more beneficent. Whatever foundations there are for these opinions, it is cer- tain that the claims of science, as a new power in the world, to the regard of thoughtful and earnest men, are receiving a re- newed and more candid attention. Through its recent prog- ress, many of the questions which have hitherto remained in the arena of metaphysical disputation are brought forward in new forms and under new auspices. Scientific investigations promise to throw a flood of light on subjects which have inter- ested mankind since the beginning of speculation, — subjects related to universal human interests. History, society, laws, and morality, — all are claimed as topics with which scientific methods are competent to deal. Scientific solutions' are pro- posed to all the questions of philosophy which scientific illumi- nation may not show to have their origin in metaphysical hal- lucination. Prominent in the ranks of the new school stands Mr. Her- bert Spencer, whose versatility has already given to the world many ingenious and original essays in this new philosophy, and whose aspiring genius projects many more, which, if his strength does not fail, are to develop the capacities of a scien- tific method in dealing with all the problems that .ought legiti- mately to interest the human mind. The programme of his future labors which his publishers have advertised might dispose a prejudiced critic to look with suspicion on what he has already accomplished; but the fa- vorable impression which his works have" made, and the plaud- its of an admiring public, demand a suspension of judgment; and the extravagance of his pretensions should for the present be credited to the strength of his enthusiasm. It is through the past labors of an author that we must judge of his qualifications for future work, and the complete- ness of his preparation. Mr. Spencer's writings evince an ex- tensive knowledge of facts political and scientific, but extensive rather than profound, and mainly at second hand. It is not, of course, to be expected that a philosopher will be an original investigator in all the departments of knowledge with which THE PHILOSOPHY OF HERBERT SPENCER. 55 he is obliged to have dealings. He must take much at second hand. But original investigations in some department of empirical science are a discipline which best tests and develops even a philosopher's powers. He has in this at least an ex- perience of what is requisite to an adequate comprehension of facts. He learns how to make knowledge profitable to the ascertainment of new truths, — an art in which the modern natural philosopher excels. By new truths must be under- stood such as are not implied in what we already know, or educible from what is patent to common observation. How- ever skillfully the philosopher may apply his analytical proc- esses to the abstraction of the truths involved in patent facts, the utility of his results will depend not so much on their value and extent as mere abstractions, as on their capacity to enlarge our experience by bringing to notice residual phenom- ena, and making us observe what w r e have entirely overlooked, or search out what has eluded our observation. Such is the character of the principles of modern natural philosophy, both mathematical and physical. They are rather the eyes with which nature is seen, than the elements and constituents of the objects discovered. It was in a clear apprehension of this value in the principles of mathematical and experi- mental science, that the excellence of Newton's genius con- sisted • and it is this value which the Positive Philosophy most prize's. But this is not the value which we find in Mr. Spen- cer's speculations. Mr. Spencer is not a positivist, though that was not a very culpable mistake which confounded his speculations with the writings of this school. Tor however much he differs from the positivists in his methods and opinions, he is actuated by the same confidence in the capacities of a scientific method, and by the same disrespect for the older philosophies. Mr. Spen- cer applies a method for the ascertainment of ultimate truths, which a positivist would regard as correct only on the suppo- sition that the materials of truth have all been collected, and that the research of science is no longer for the enlargement of our experience or for the informing of the mind. Until these conditions be realized, the positivist regards such at- 5 6 PHILOSOPHICAL DISCUSSIONS. tempts as Mr. Spencer's as not only faulty, but positively per- nicious and misleading. Nothing justifies the development of abstract principles in science but their utility in enlarging our concrete knowledge of nature. The ideas on which mathematical Mechanics and the Calculus are founded, the morphological ideas of Natural History, and the theories of Chemistry are such working ideas, — finders, not merely sum- maries of truth. But before examining more in detail Mr. Spencer's method of philosophizing, it will be useful to consider his career and character as a thinker and writer. Born in Derby in 1820, he was educated by his father, who was a school-teacher in that town, and by his uncle, a clergyman of the Established Church. At the age of seventeen he entered on the profes- sion of civil engineering, which he followed for eight years. He then abandoned this pursuit for a literary career. He had already published in a scientific journal several papers on pro- fessional subjects, and at the age of twenty-two gave an ear- nest of his tastes for political speculation in a newspaper article on "The Proper Sphere of Government." He after- wards became a writer in the Economist, and in 1851 pub- lished his "Social Statics, or the Conditions essential to Human Happiness specified, and the First of them devel- oped." By this work he became first generally known to the reading public in America. This work exhibits the traits which characterize all Mr. Spencer's subsequent writings. A constant and close student of facts both political and scientific, with the practical bent of the English radical and idealist, he is none the less strongly attracted to the abstractions of speculative thought. He aims at the same time at system and at effect. No distract idealist, though always actuated by that uncontent which moves revolutions and reforms, he uses abstractions and abstract modes of thought for moral ends, His allegiance to his speculative and his practical aims seems sometimes divided, and then he shows a tendency to follow out the consequences of theory, and to trust the welfare of mankind to its omnipotent care. He has great faith in the self-sufficingness of things. The very elements have in them THE PHILOSOPHY OF HERBERT SPENCER. 57 the seeds of moral perfectibility. But he would leave out of the category of natural agencies in politics the paternal care of the rulers of mankind. He regards with lofty scorn that presumption in the governing classes which pretends to com- prehend and help forward the inherent progressiveness of the world. Moral idealism colors all Mr. Spencer's views, both in science and politics. This gains him a popular hearing, es- pecially with the youth of democratic America. But Amer- ican democracy itself sympathizes with English radicalism only as the rich and benevolent sympathize with the poor. We wish them the good of universal suffrage. We are studying how to remedy the evils of it. To us this boon is a present fate, mixed of good and evil, — a thing neither to seek nor to avoid, but of which we must make the best. We suffer our legislators to exercise that absolute tyranny which Mr. Spencer proves to be an absolute immorality, — a compulsory universal common-school education, — without a murmur. We have not even suspected its immorality. Some of us regard it as a little overdone; but few or none have found that the system is radically faulty, though it be at variance with Mr. Spencer's moral premises. But we must defer the consideration of the arguments of this work, for we are at present only concerned with the characteristics of the writer. The strong tendency to speculative and abstract modes of thought which his first work evinces found a more distinct utterance in the author's " Principles of Psychology," published four years later, in 1855. The choice of this subject seems to have been determined by the author's genius for the kind of thinking to which this subject is adapted, rather than by any special training in its literature. Indeed, this work, like the " Social Statics," is characterized by great originality. Con- strained by his entire sympathy with modern movements in thought and scientific culture, he is perforce a scientific em- piricist, though his peculiar genius would have found a more congenial employment in scholastic philosophy. Mr. Spen- cer believes in developments. All his writings are develop- ments, and most of them are about developments. He de- lights in "evolutions from the homogeneous to the heterogene- 58 PHILOSOPHICAL DISCUSSIONS. ous," — in " changes from an indefinite incoherent homogeneity to a definite coherent heterogeneity, through continuous differ- entiations and integrations." He not only discovers them in all the objects of scientific research, but he rings these changes in all his discourses on them. Analysis is his forte, and devel- opments are foibles. But he had not yet in his "Principles of Psychology" fully developed these foibles. He finds, however, in the problems of Psychology scope for his analytical powers. Like all writers who do not speak from the urgency of con- viction or dissent, he is an eclectic. He aims to combine in his Psychology what is true in empiricism with what is true in metaphysics ; and he had special reasons for this course. Mr. Spencer is here no longer a champion. His moral convictions find their utterance in his political and social essays. In Phi- losophy he is charmed with ideas, and with his power to un- ravel them. He is actuated by a simple love of truth, and he is therefore an eclectic. He has no real respect for ideas or for the religious grounds of metaphysics. As between pure empiricism and religious metaphysics his choice would be un- hesitating. He would choose empiricism. But ideas are fine things when one has more power to unfold than to find them ; and they are still found, as heretofore, by the insights of scien- tific sagacity rather than by any method. Pure empiricism, however, or Positivism, refuses to Psychology any place in the hierarchy of the sciences. How then can Mr. Spencer get the ideas on which to exercise his powers ? There is only one course ; he must postulate them. Ideas are all derived from experience, it is true ; but we must not seek in actual particu- lar experiences for their validity. These may be, and probably are, beyond the reach of resuscitation. What then is the test of truth or of reality in the grounds of any idea ? " The in- conceivableness of its negation," says Mr. Spencer; and so he adopted a principle from metaphysics, but with a limitation. This inconceivableness results from the discipline of experience. It does not depend on any plastic power of the mind as an original nature, determining the possibilities of experience and thought, but it is determined in the mind by invariable experi- ences. Those orders and relationships of events in nature THE PHILOSOPHY OF HERBERT SPENCER. 59 which are present to the mind from its first determinations to thought, those which are never contradicted in experience, de- termine also the possibilities of thought ; and in turn the possi- bilities of thought are tests of invariable experiences, though the particular experiences are lost in oblivion. In other words, the mind has but one faculty peculiarly its own, and that is memory. The mind is pure memory, but this has various forms. The primordial memory, the intellect, that which is as it were the framework of all the others, — the containing mem- ory, — consists of certain beliefs, the negations of which cannot be conceived, but the particular grounds of which are forgot- ten. This memory extends back of the individual life, is de- rived from the experience of the race, and constitutes the in- nate tendencies and mental powers with which the individual life begins. This sounds like Plato's doctrine, that learning is a kind of reminiscence ; but it is in fact pure empiricism. Mind is but a reflex of organism. But the organism has a memory, — a memory of the results of all invariable experiences in the continuous evolutions of the race. No empiricist can find any radical fault with this account of innate ideas. But Mr. Spencer evolves it in a somewhat different manner. He is seeking for a basis of psychology which shall be consist- ent with the truth of empiricism, and at the same time- with the possibility of psychology as a distinct science. Some first truth or truths peculiarly psychological are wanted, for Mr. Spencer proposes to try his speculative powers in eliciting what has eluded the sagacity of his predecessors in psychology, — in the analysis of ideas. Now, the existence of beliefs, proved to be invariable by the inconceivableness of their negations, is a fundamental fact of consciousness, — the most fundamental fact. Beliefs of all sorts are the constituent elements of con- . sciousness. Every act of the mind involves a judgment, that is, a belief; and the only test, indeed the only meaning, of the truth of a belief is \Xs persistency . Hence in variableness in a belief, as proved by the inconceivableness of its negation, is the highest possible warrant of truth. Sensible experience can give no higher warrant. The mind, therefore, contains in itself the criterion of truth j and psychology, or a scientific 60 PHILOSOPHICAL DISCUSSIONS. evolution of the data of consciousness, is a legitimate philoso- phy. And this is thought to be not inconsistent with the em- pirical explanation of the origin of invariable beliefs, namely, the formation of the mind by invariable, often repeated, special experiences, both in the individual and in the race. But there is a superfluity somewhere, — too many authorities. Occam's razor is not too old to apply to this new philosophy. The characteristic common to particular, real experiences, and to universal, necessary truths, so called, — namely, that they are believed, and believed without appeal to anything else, — this characteristic is either from the same or from different sources. If from different sources, then empiricism is false, and Psy- chology is a legitimate philosophy. If from the same source, namely, particular experiences, then these are a sufficient au- thority, and indeed the only final appeal, though invariable beliefs, "proved to be invariable by the inconceivableness of their negations," may be excellent approximate determinations of what experience certifies. No empiricist will deny this ex- cellence to natural beliefs, but this is not ascribing to them any proper authority. In discussing this his criterion or " universal postulate," Mr. Spencer encounters two of the acutest of modern thinkers, Mr. Mill and Sir William Hamilton, whose opinions he finds opposed to his own on opposite grounds. Here is a fine chance for eclecticism, to combine what is true in both these philosophies ; but first he must refute what is false. Speaking of the effect of habit in determining the limits of our conceptive faculty, Mr. Mill says : " There are remarkable instances of this in the history of science ; instances in which the wisest men rejected as impossible, because inconceivable, things which their posterity, by earlier practice and longer perseverance in the attempt, found it quite easy to conceive, and which everybody now knows to be true." While grant- ing that this evidence is sufficient to disprove the doctrine of the a priori character of our natural beliefs, our author thinks that "it does not really warrant Mr. Mill's inference, that it is absurd to reject a proposition as impossible on no other grounds than its inconceivableness." Further on he says: THE PHILOSOPHY OF HERBERT SPENCER. 6 1 " If there be, as Mr. Mill holds, certain absolute uniformities in nat- ure; if these uniformities produce, as they must, absolute uniformities in our experience ; and if, as he shows, these absolute uniformities in our experience disable us from conceiving the negations of them, — then, answering to each uniformity in nature which we can cognize, there must exist in us a belief of which the negation is inconceivable, and which is absolutely true. In this wide range of cases subjective inconceivable- ness must correspond to objective impossibility. Further experience will produce correspondence where it may not yet exist ; and we may expect the correspondence to become ultimately complete. In nearly all cases this test of inconceivableness must be valid now ; and where it is not, it still expresses the net result of our experience up to the present time ; which is the most that any test can do." True, — the most that any empirical test can do ; but is not Mr. Spencer's test, " the universal postulate," exempt from this imperfection ? If not, how does it warrant rejecting as impos- sible an inconceivable proposition, on no other ground than its inconceivableness ? Mr. Spencer's argument, condensed and completed, is this. If there be any such things as universal necessary truths, then invariable beliefs must result from them ; but we have invariable beliefs, therefore they must be the tests of truth ! If A exists, then B exists ; but B exists, therefore — Mr. Spencer must find the conclusion in his own logic : neither Modus Foncns nor Modus Tollens will serve. "But," he continues, "the inconsistency into which Mr. Mill has thus fallen is most clearly seen in the second of his two chapters on 'Dem- onstration and Necessary Truths.' He admits in this the validity of proof by a rednclio ad absurdum. Now what is a reduclio ad absurdum, unless a reduction to inconceivableness ? And why, if inconceivableness be in other cases an insufficient ground for rejecting a proposition as im- possible, is it a sufficient ground in this case ? " After quoting other passages from Mill, Mr. Spencer says of them : "Here, and throughout the whole of his argument, Mr. Mill assumes that there is something more certain in a demonstration than in anything else, — some necessary truth in the steps of our reasoning which is not possessed by the axioms they start from. How can this assumption be justified ? In each successive syllogism, the dependence of the conclusion upon its premises is a truth of which we have no other proof than the in- conceivability of the negation. Unless our perception of logical truth is a priori, which Mr. Mill will not contend, it too, like our perceptions of mathematical truth, has been gained from experience," etc. 62 PHILOSOPHICAL DISCUSSIONS. Now all this shows a grand confusion in Mr. Spencer's mind. He bases his postulate, the ultimate test of all truth, on two hypotheses, — the existence of universal facts or absolute uni- formities in nature, and their effect in producing invariable beliefs in the mind ; and because Mr. Mill allows these as em- pirical generalizations, he is regarded as inconsistent in not allowing the character of necessity to an imperfect conclusion from them ! But Mr. Mill does not deny to natural beliefs a proximate or derivative authority. Both logical axioms and the axioms to which they are applied in reasoning may safely be taken as properly accredited from experience ; but their author- ity is secondary, and such authority is not always to be trusted, as Mr. Mill's historical example shows. The imperfect argu- ment, " If A, then B, but B," proves nothing absolutely, but it may determine a probability. Mr. Mill maintains that there are degrees of trustworthiness in natural beliefs, as well as in the so-called empirical beliefs, and that this trustworthiness depends absolutely, not on the strength of our beliefs, whether this be absolute or not, but on particular experiences, ultimately and absolutely. Mr. Spencer endeavors to explain away Mill's historical ex- ample, — the fact that certain Greek philosophers could not credit the existence of antipodes, — by the consideration that the conception, which seemed impossible to these philosophers, is really a complex one, whereas the truths which are properly attested by the inconceivableness of their negations are sim- ple "undecomposable" ones. He therefore puts a modifying clause into his canon. It is necessary that the ideas so tested be simple. The mind in the confusion of compound ideas may think that it conceives what it really does not conceive, and that it cannot conceive what it really can conceive. The certainty of the application of the test depends on the number of really independent applications which it involves, in each of which the mind is liable to a slip of the attention. Mistakes from a -•con fusion of matters are quite independent of the essential trustworthiness of our primary sources of knowledge. Even the senses may get confused. Why not, then, our invariable ideas ? Easily : for does not Mr. Spencer himself confound the THE PHILOSOPHY OF HERBERT SPENCER. 6$ authority of our natural beliefs with their utility in directing us to what our experiejices certify ? Mr. Spencer is mistaken in supposing that any middle ground is possible between empiricism and metaphysics, or that the characteristic ideas of these two philosophies can be reconciled by the hypothesis of organized experiences, anterior to the life of the individual mind. In these experiences, as in those of the individual life, particular facts are the real author- ities, as is evinced by what Mr. Spencer cannot deny, that such facts are competent to overthrow the most settled beliefs. It avails nothing to say that such facts cannot be experienced, the mind being, ex hypothesis unable to conceive them even if they exist ; for this is to convict natural beliefs and the mind itself of incompetency, not to establish these beliefs as compe- tent authorities. In reviewing previous attempts to find an independent basis for Psychology, Mr. Spencer encounters Sir William Hamil- ton's philosophy of Common-Sense. After quoting Hamilton's leading maxims, that "Consciousness is to be presumed trust- worthy until proved to be mendacious," and that "the men-' dacity of consciousness is proved, if its data immediately in themselves, or mediately in their necessary consequences, be shown to stand in mutual contradiction," he says: " Now a sceptic might very properly argue that this test is worthless. For as the steps by which consciousness is to be proved mendacious are themselves states of consciousness ; and as they must be assumed trust- worthy in the act of proving that consciousness i's not so ; the process results in assuming the trustworthiness of particular states of conscious- ness, to prove the mendacity of consciousness in general. Or to apply the test specifically: — Let it be shown that two data of consciousness stand in contradiction. Then consciousness is mendacious. But if con- sciousness is mendacious, then the consciousness of this consciousness is mendacious. Then consciousness is trustworthy. And so on forever." But the condition of vacillation to which Mr. Spencer re- duces the sceptic's application of Hamilton's criterion is itself the true condition of scepticism. Mr. Spencer seems to mean by scepticism a dogmatic scepticism, — if we may be allowed the expression, — or a negative dogmatism ; whereas Hamilton means by scepticism a negation of all philosophical judgments, 64 PHILOSOPHICAL DISCUSSIONS. the " what do I know ? " condition of a mind confused about authorities; and Mr. Spencer has really given an excellent illustration of the application of these maxims, while seeking to depreciate their value. But the condition of scepticism is best illustrated by the original of the sophism to which he rer duces Hamilton's maxims. " If you say that you lie, and say so truly, then you do lie; but if you say so falsely, then you speak the truth. In either case, therefore, the same statement is both true and false." To the fearful consequences of such lying is the sceptic reduced who doubts the testimony of con- sciousness. Mr. Spencer gives to this sophism the more com- mon but inferior form, of which the original is this : " All Cretans are liars. But Epimenides, who says this, is himself a Cretan. Therefore, as he is a liar, this saying is not true. But if the saying is not true, Epimenides may have spoken the truth. Then the saying is true : — and so on as before." In his singular misapprehension of the meaning of the word " scep- ticism" in philosophy, Mr. Spencer illustrates another trait of his writings. He means by '-sceptic" one who doubts the essential doctrines of orthodox philosophy, "natural realism," "personal identity," "the possibility of a science of psychol- ogy," and the like; and as he is opposed to such sceptics, he gives the impression to the world that he is ranged on the side of orthodoxy. But it is only with the husks of orthodoxy that he feeds his flock. He does not defend its doctrines as Ham- ilton did in the interests of dogmatic theology and religion, but simply from the vanity of disputation. It cannot be said of Hamilton's criterion, that it is of any greater value than Mr. Spencer's, or that it yields anything more as a principle of research, but it at least has the merits of self-consistency and distinctness. In reviewing the objections to the test of inconceivableness, Mr. Spencer again finds himself opposed to Sir William Ham- ilton. The doughty knight is encased in a seemingly invulner- able logic, and impedes the progress of truth. After stating certain minor and indecisive objections to the doctrine of the "conditioned," Mr. Spencer waives them. •' Granting ail this," he says, "Sir William Hamilton's argument may THE PHILOSOPHY OF HERBERT SPENCER. 65 still be met. He says that inconceivability is no criterion of impossi- bility. Why ? Because of two propositions, one of which must be true ; it proves both impossible, — it proves that space cannot have a limit, be- cause a limit is inconceivable, and yet that it has a limit, because unlimited space is inconceivable ; it proves, therefore, that space has a limit and has no limit, which is absurd. How absurd? Absurd because 'it is impos- sible for the same thing to be and not to be. ' But how do we know that it is impossible for the same thing to be and not to be ? What is our criterion of this impossibility? Can Sir William Hamilton assign any other than this same inconceivability ? If not, his argument is self- destructive ; seeing that he assumes the validity of the test in proving its invalidity." This is the same shaft ad hominem which Mr. Spencer lev- eled at Mill, and it glances for the same reason. He does not precisely apprehend the position of his antagonist. Hamilton's argument is not self-destructive, since it is only designed to prove the incompleteness of the test, which Mr. Spencer has adopted in its baldest and crudest form. What was an obvi- ous petitio pincipii as applied to Mr. Mill, namely, ascribing to him the opinion that logical axioms rest ultimately on the test of the inconceivableness of their negations, is none the less really such as applied to Hamilton's doctrines. Ham- ilton can and does assign a different criterion. Mr. Mill ap- peals to particular experiences as the tests, in the proper sense of that word, of all axioms logical or mathematical ; while Hamilton admits for them a psychological test, analogous to Mr. Spencer's, yet more complete. "A proposition which can be conceived, but of which the negation cannot be conceived, is true, and its negation is false," is the complete formula. The conceivable and inconceivable correspond to the possible and impossible only when logically opposed to each other. If two conceivables could be logically opposed to each other, we should have scepticism in the philosophical sense of the word, or as Hamilton uses it. If two inconceivables are logically op- posed, we have no test of true or false ; yet not that vacillation of the mind, that uncertainty, which is the characteristic of scepticism. But we have the feeling that there is truth beyond the power of knowledge, or that "the domain of our knowl- edge is not co-extensive with the horizon of our faith;" for a principle of truth — the principle of non-contradiction — is 66 PHILOSOPHICAL DISCUSSIONS. seen to extend where sense and imagination and our powers of conception cannot follow. This decides nothing positively. It only shows that unbelief or negative dogmatism is unfound- ed, and it opens the way for the authority of religious feeling, in whose behalf the contests of philosophy are undertaken by all but such pretended champions as Mr. Spencer. Hamilton went to the extremest verge in the direction of empiricism which it was possible to reach, without renouncing the inter- ests for which philosophy proper has always been cultivated. Empiricism has other interests, worthy interests, but they are not religious. It was necessary to a philosophical defense of religious doc- trines to establish logical axioms on a broader basis than ex- perience can afford, in order to secure a ground for belief in truths which are inconceivable, or truths of which the terms cannot be united in a judgment either by proofs from what is really known or by intuition; and in order also to reason about such truths, and bring the objects of religious feeling, partially at least, within the scope of our thoughts. Such are the mo- tives for metaphysical philosophy, and such indeed are the only grounds for metaphysics. Philosophy converts practical rea- sons or final causes into theoretical reasons, and postulates a faculty where there is only a feeling. But after all, that which the Best in us most prizes is not so much the service of Phi- losophy as that for which this service is undertaken. Mr. Spencer pursues his discussion of this subject in the first part of his recently published work, the " First Principles of a New System of Philosophy," to the consideration of which we shall presently come. Of his further developments in Psy- chology we can only say that they are very wearisome. He makes little explicit use of his postulate ; for this, after all, is only a license to take any ideas one chooses for the bases of science, if one only cannot conceive their negations. It is one of those unproductive principles which Positivism condemns; and he develops others equally useless, except in the mental discipline there may be in following their evolution. One such application of his method is in search of a definition of Life, which after a development in as many pages results in these THE PHILOSOPHY OF HERBERT SPENCER. 67 words : " Life is defined as — The definite combination of heterogeneous changes, both simultaneous and successive, in correspondence with external co-existences and sequences." These words are sufficiently abstract to be of some scientific service, but they only make Life the more perplexing, which had mysteries enough before. But we ought not to prejudge. Perhaps Mr. Spencer will be able, when he comes to treat of Morality in his new philosophy, to apply this definition in elucidating the principles of correct living. But to return to the argument of his " Social Statics." This is a thorough-going application of one of the conditions of human happiness to all the relations of human life,— namely, the Law of Liberty, or the " Let alone Principle." To warrant the ex- clusive application of this principle to the deduction of social laws and the limits of state powers, he postulates it as a part or one side of a perfect law, of which we have knowledge through a moral sense. This sense has not an a priori char- acter, as the metaphysicians maintain, but is derived from the observation, by the human race as a whole, of the conditions essential to human happiness on the whole, and is developed in our nature with the evolution of civilization, as the instinct which cares for the interests of society, just as the bodily appe- tites are produced to care for the interests of the individual organism. This doctrine is perfectly analogous to that which he develops more explicitly in the "Principles of Psychology " concerning the origin and character of natural beliefs. He makes the same mistake in basing a criterion on an hypothesis, and he is inconsistent in the same way in ascribing to his "moral sense" an original authority. With the exception of these errors, there is nothing in his doctrine of moral sense with which the utilitarian can find fault. But he develops his ideas in this his earlier work so inexplicitly, that not only Mr. Mill,* but many others, have mistaken him for an opponent of utilitarianism. By ascribing an absolute authority to intellect- ual and moral ideas, when on his principles he ought only to have ascribed to them a relative and derivative one, he was led into mistakes which have given rise to misinterpretations of his See Essay on Utilitarianism. 68 PHILOSOPHICAL DISCUSSIONS. doctrines, — misinterpretations of which he cannot justly com- plain. But he has also gained a reputation for orthodoxy, which he does not deserve. Mr. Spencer succeeds better in his shorter essays, many of which for ingenuity, originality, and scientific interest have been rarely surpassed. But judging only by his writing and the general character of his thinking, we should not ascribe to him that precision in the apprehension of scien- tific facts which comes chiefly from a successful cultivation of experimental and mathematical research in natural history and natural philosophy. To learn only the results of such researches and the general character of their processes is not enough. One must also be qualified to pursue them. The fact that Mr. Spencer was at one time a civil engineer seems to militate against this judgment of his qualifications. But though a marked success and a reputation acquired in this pursuit would be of great weight in determining our judgment, yet, in the absence of any evidence of this kind, we adhere to the opinion we have formed from his writings. We will say nothing of the impossibility of any one man's acquiring adequately all the knowledge requisite for the successful ac- complishment of such an undertaking as Mr. Spencer has pro- posed for himself. But a part of this work has become an accomplished fact. The "First Principles" of the new system of philosophy has appeared, and a serial publication of parts of another work on the "Principles of Biology" is now in progress. Mr. Spencer modestly omits from his gigantic scheme any special consider- ation of physics or the principles of inorganic nature ; although his training in mathematics and engineering would seem at first sight to be a preparation best suited to this subject. Perhaps he regards this science as standing in little need of his develop- ments, and besides he has already published some of his views on this subject in his essay on the Nebular Hypothesis, and his "First Principles" involve generalizations from physical theories. To the positivists the sciences of general physics, that is As- tronomy, Mechanical and Chemical Physics, and Chemistry, THE PHILOSOPHY OF HERBERT SPENCER. 69 afford the patterns for all the sciences, and some, like Physiol- ogy/ are beginning to profit by such examples. But Mr. Spen- cer does not find in general physics free play for his ideas. It is only in what constitutes the problems and obscurities of these sciences that he finds free exemplifications of his principles. In the nebular hypothesis and in the obscure relations of phys- ical forces to organic life, and in. the hypothesis of the develop- ment of organic life through successive geological eras, he is at home. He is conscious of the temptation there is to im- pose teleological interpretations upon the obscurities of science; and he therefore aims to free his speculations as much as possi- ble from these biases, but with as little success as he had in his Psychology in correcting the errors of metaphysics by the light of empirical science. The idea which has exercised the profoundest influence on the course of Mr. Spencer's thought, as well as on all thought in modern times, and one which appears more or less distinct- ly in nearly all of Mr. Spencer's writings, is the idea which he elaborates in his " First Principles " as the " Law of Evolution.'-' But what is the origin and value of this idea ? Ostensibly it was derived from the investigations of the physiologists in em- bryology, from Harvey down to the present time. The formula of Von Baer was the first adequate statement of it. This for- mula Mr. Spencer has elaborated and completed, so as to apply, he thinks, not only to the phenomena of embryology, but to the phenomena of nature generally, and especially, as it appears, to those which we know least about, and to those which we only guess at. But while this is the ostensible origin and scientific value of this idea, its real origin is a very curious and instructive fact in human nature. Progress is a grand idea, — Universal Progress is a still grander idea. It strikes the key-note of modern civil- ization. Moral idealism is the religion of our times. What the ideas God, the One and the All, the Infinite First Cause, were to an earlier civilization, such are Progress and Universal Progress to the modern world, — a reflex of its moral ideas and feelings, and not a tradition. Men ever worship the Best, and the consciousness that the Best is attainable is the highest moral 7 o PHILOSOPHICAL DISCUSSIONS. consciousness, the most inspiring of truths. And when in- dications of that attainment are visible not merely to the eye of faith, but in sensible progress, scientifically measurable, civ- ilization is inspired with a new devotion. Faith that moral per- fectibility is possible, not in remote times and places, not in the millennium, not in heaven, but in the furtherance of a present progress, is a faith which to possess in modern times does not make a man suspected, of folly or fanaticism. He may forget the past, cease to be religious in the conventional sense of the word, but he is the modern prophet. When Plato forsook the scientific studies of his youth, and found the truest interpretations of nature by asking his own mind what was the best, according to which, he felt sure, the order and framework of nature must be determined, he did but illustrate the influence which strongly impressed moral ideas have on speculative thought at all times ; but he did it con- sciously and avow r edly. Modern thinkers may be less conscious of this influence, may endeavor to suppress what consciousness they have of it, warned by the history of philosophy that tele- ological speculations are exploded follies ; nevertheless, the in- fluence surrounds and penetrates them like an atmosphere, un- less they be moral phlegmatics and mere lookers-on. It was Mr. Spencer's aim to free the law of evolution from all teleological implications, and to add such elements and lim- itations to its definition as should make it universally applica- ble to the movement of nature. Having done this, as he thinks, he arrives at the following definition : " Evolution is a change from an indefinite incoherent homogeneity to a definite coherent heterogeneity through continuous differentiations and integra- tions." But teleology is a-.subtile poison, and lurks where least suspected. The facts of the sciences which Dr. Whewell calls palsetiological, like the various branches of geology, and every actual concrete series of events which together form an object of interest to us, are apt, unless we are fully acquainted with the actual details through observation or by actual particular deductions from well-known particular facts and general laws, to fall into a dramatic procession in our imaginations. The mythic instinct slips into the place of the chronicles at every THE PHILOSOPHY OF HERBERT SPENCER. 71 opportunity. All history is written on dramatic principles. All cosmological speculations are strictly teleological. We never can comprehend the whole of a concrete series of events. What arrests our attention in it is what constitutes the parts of an order either real or imaginary, and all merely imaginary or- ders are dramatic, or are determined by interests which are spontaneous in human life. Our speculations about what we have not really observed, to which we supply the order and most of the facts, are necessarily determined by some principle of order in our minds. Now the most general principle which we can have is this : that the concrete series shall be an in- telligible series in its entirety ; thus alone can it interest and attract our thoughts and arouse a rational curiosity. But to suppose that such series exist anywhere but where observation and legitimate particular inferences from observa- tion warrant the supposition, is to commit the same mistake which has given rise to teleological theories of nature. The "law of causation," the postulate of positive science, does not go to this extent. It does not suppose that there are through- out nature unbroken series in causation, forming in their en- tirety intelligible wholes, determinable in their beginnings, their progressions, and their ends, with a birth, a growth, a maturation, and a decay. It only presumes that the perhaps unintelligible wholes, both in the sequences and the co-exist- ences of natural phenomena, are composed of intelligible ele- ments ; that chaos does not subsist at the heart of things ; that the order in nature which is discernible vaguely even to the unobservant implies at least a precise elementary order, or fixed relations of antecedents and consequents in its ultimate parts and constituents ; that the apparently irregular heterogeneous masses, the concrete series" of events, are crystalline in their substance. To discover these elementary fixed relations of antecedents and consequents, is the work of scientific induction ; and the only postulate of science is, that these relations are everywhere to be found. To account, as far as possible, for any concrete order, intelligible as a whole, or regular, like that of life, is the work of scientific explanation, by deductions from the element- 72 PHILOSOPHICAL DISCUSSIONS. ary fixed relations which induction may have discovered. But to explain any such order by simply defining it externally in vague, abstract terms, and to postulate such orders as the components of nature and parts of one complete and intelligi- ble order, is to take a step in advance of legitimate speculation, and a step backward in scientific method, — is to commit the mistake of the ancient philosophies of nature. But Mr. Spencer thinks he has established his "Law of Evo- lution" by induction. The examples from which he has an- alyzed his law, the examples of progress in the development of the several elements of civilization, such as languages, laws, fashions, and ideas, — the hypothetical examples of the Nebular Hypothesis and the Development Hypothesis, and the example of embryological development (the only one our conceptions of which are not liable to be tainted by teleological biases), — are examples which, according to Mr. Spencer's philosophy, afford both the definition and its justification. In other words, his definitions are only carefully elaborated general descriptions in abstract terms ; or statements of facts which are observed in numerous instances or classes of instances, in terms detached from all objects, in abstract terms, of which the intension is fully known, but of which the extension is unknown except through the descriptions they embody. This, though a useful, is a precarious kind of induction, and is apt to lead to prema- ture and false generalizations, or extensions of descriptions to what is hypothetical or unknown. Such inductions are liable to be mistaken for another sort, and to be regarded as not merely general, but universal descriptions, and as applicable to what they do not really apply to. This liability is strong just in proportion as prominence is given to such definitions in a philosophical system. No convert to Mr. Spencer's philosophy doubts the substantial correctness of the Nebular and Devel- opment Hypotheses, though these are only hypothetical ex- amples of Mr. Spencer's law. The other surt of inductions to which we have referred are peculiar to the exact inductive sciences. Facts which are not merely general, but, from their elementary character and their immediate relations to the orderliness of nature, are presumed THE PHILOSOPHY OF HERBERT SPENCER. 73 to be universal facts, are the sort which the positive philosophy most prizes, and of which the law of gravitation is the typical example. The honor must be conceded to Mr. Spencer of hav- ing elaborated a precise and very abstract description of cer- tain phenomena, the number, the other characters, and the ex- tent of which are, however, unknown, but are all the more imposing from this circumstance. The law of gravity was a key which deciphered a vast body of otherwise obscure phenomena, and (what is more to the purpose) was successfully applied to the solution of all the problems these phenomena presented. It is common to ascribe to Newton the merit of having discovered the law of gravity, in the same sense in which Mr. Spencer may be said to have dis- covered his law. The justness of this praise may well be doubt- ed ; for others had speculated and defined the law of gravity before Newton. What he really discovered was the universality of this law, or so nearly discovered it that the astronomers who completed the investigation did not hesitate to concede to him the full honor. He established for it such a degree of probability that his successors pursued the verification with un- hesitating confidence, and still pursue it, in the fullness of faith. - Mr. Spencer's law is founded on examples, of which only one class, the facts of embryology, are properly scientific. The others are still debated as to their real characters. Theories of society and of the character and origin of social progress, the- ories on the origins and the changes of organic forms, and the- ories on the origins and the causes of cosmical bodies and their arrangements, are all liable to the taint of teleological'and cos- mological conceptions, — to spring from the order which the mind imposes upon what it imperfectly observes, rather than from that which the objects, were they better known, would supply to the mind. To us Mr. Spencer's speculation seems but the abstract state- ment of the cosmological conceptions, and that kind of order- liness which the human mind spontaneously supplies in the absence of facts sufficiently numerous and precise to justify sound scientific conclusions. Progress and development, when they mean more than a continuous proceeding, have a mean- 4 74 PHILOSOPHICAL DISCUSSIONS. ing suspiciously like what the moral and mythic instincts are inclined to, — something having a beginning, a middle, and an end, — an epic poem, a dramatic representation, a story, a cos- mogony. It is not sufficient for the purposes of science that the idea of progress be freed from any reference to human happiness as an end. Teleology does not consist entirely of speculations having happy denouements , save that the perfection or the end to which the progress tends is a happiness to the intellect that contemplates it in its evolution and beauty of orderliness. Plato's astronomical speculations were teleolog- ical in this artistic sense. It is not sufficient for the purposes of science, that the idea of progress be thus purified ; and it would be better if science itself were purified of this idea, at least until proof of its extent and reality be borne in upon the mind by the irresistible force of a truly scientific induction. Aristotle exhibited the charac- teristics of scientific genius in no way more distinctly than in the rejection of this idea, and of all cosmological speculations. But there is a truth implied in this idea, and an important one, — the truth, namely, that the proper objects of scientific re- search are all of them processes and the results of processes ; not the immutable natures which Plato sought for above- a world of confusion and unreality, in the world of his own in- telligence, but the immutable elements in the orders of all changes, the permanent relations of co-existences and sequences, which are hidden in the confusions of complex phenomena. Thought itself is a process and the mind a complex series of processes, the immutable elements of which must be dis- covered, not merely by introspection or by self-consciousness, but by the aid of physiological researches and by indirect observation. Everything out of the mind is a product, the result of some process. Nothing is exempt from change. Worlds are formed and dissipated. Races of organic beings grow up like their constituent individual members, and dis- appear like these. Nothing shows a trace of an original, im- mutable nature, except the unchangeable laws of change. These point to no beginning and to no end in time, nor to any bounds in space. All indications to the contrary in the results THE PHILOSOPHY OF HERBERT SPENCER. 75 of physical research are clearly traceable to imperfections in our present knowledge of all • the laws of change, and to that disposition to cosmological speculations which still prevails even in science. We propound these doctrines not as established ones, but as having a warrant from the general results of physical research similar to that which the postulate of science, the law of causa- tion, has in the vaguely discerned order in nature, which forces itself on the attention even of the unobservant. But as a mind unfamiliar with science is easily persuaded that there are phenomena in nature to which the law of causation does not apply, phenomena intrinsically arbitrary and capricious, so even to those most familiar with our present knowledge of physical laws, but who have not attended to the implication of their general characters and relations, the supposition is not in- credible that there is a tendency in the forces of nature to a permanent or persistently progressive change in the theatre of their operations, and to an ultimate cessation of all the partic- ular conditions on which their manifestations depend. To show why this is incredible to us would carry us beyond the proper limits of our subject, were it not that our author has speculated in the same direction. Having developed what he thinks to be the true scientific idea of progress in his " Law of Evolution," Mr. Spencer next considers its relations to ultimate scientific ideas, the ideas of space, time, matter, and force. As evolution is change, and as change, scientifically comprehended, is comprehended in terms of matter, motion, and force, and the conditions necessary to these, or time and space, it is necessary that evolution be fur- ther defined in its relations to these ideas. These are only for- mulating terms, entirely abstract. They imply no ontological theory about the nature of existence of mind or matter; and when Mr. Spencer proposes to formulate the. phenomena of mind as well as those of matter in terms of matter, motion, and force, it is because these ideas are the only precise ones in which the phenomena of change can be defined. Mr. Spencer is not a materialist. Materialism and spiritual- ism, or psychological idealism, are as dogmatic theories equally 7 6 PHILOSOPHICAL DISCUSSION'S. self-contradictory and absurd. Mr. Spencer is neither a mate- rialist nor an idealist; neither theist, atheist, nor pantheist. All these doctrines are, he thinks, without sense or reason; and the philosophers who invented them, and the disciples who re- ceived and thought they understood them, were deceived. But we are inclined to the opinion that believers, though they may be deceived about their ability to comprehend these theories (for it is easy to mistake meanings), are not deceived about the motives or the spirit which prompts these speculations, and which in fact determines for each his election of what doctrine best suits his character. For within the pale of philosophy, character determines belief, and ideas stand for feelings. We receive the truths of science on compulsion. Nothing but ig- norance is able to resist them. In philosophy we are free from every bias, except that of our own characters ; and it therefore seems to us becoming in a philosopher, who is solicitous about the moral reputation of his doctrines, and who would avoid classification under disreputable categories, that he teach noth- ing which he does not know, lest the direction of his inquiries be mistaken for that of his dispositions. The vulgar who use the obnoxious terms, materialism, atheism, pantheism, do not pretend to define them; but they somehow have a very definite idea, or at least a strong feeling, about the dangerous character of such speculations, which appear none the less reprehensible because inconceivable. But we must defer the considerations of the moral character of Mr. Spencer's speculations, until we have further examined their scientific grounds. Terms which the real physicist knows how to use as the terms of mathematical formulas, and which were never even suspected of any heterodox tendencies, terms which have been of inestimable service both in formulating and finding out the secrets of nature, are appropriated by Mr. Spencer to the fur- ther elaboration of his vague definitions, and to the abstract description of as much in real nature as they may happen to apply to. As if an inventory of the tools of any craft were a proper account of its handiwork ! Out of mathematical for- mulas these terms lose their definiteness and their utility. THE PHILOSOPHY OF HERBERT SPENCER. 77 They .become corrupting and misleading ideas. They are none the less abstract, but they are less clear. They again clothe themselves in circumstance, though vaguely. They ap- peal to that indefinite consciousness which, as Mr. Spencer says, cannot be formulated, but in which he thinks we have an ap- prehension of cause and causal agencies. "Though along with the extension of generalizations, and concomitant integrations of conceived causal agencies," says Mr. Spencer, "the con- ceptions of causal agencies grow more indefinite ; and though as they gradually coalesce into a universal causal agency they cease to be repre- sentable in thought, and are no longer supposed to be comprehensible, yet the consciousness of cause remains as dominant to the last as it was at first, and can never be got rid of. The consciousness of cause can be abolished only by abolishing consciousness itself." This is quoted by himself from his " First Principles," as one of his "reasons for dissenting from the philosophy of M. Comte." Though he seems solicitous to avoid all ontological implications in his use of scientific terms, yet we cannot avoid the impression of a vague metaphysical signification in his speculations, as if he were presenting all the parts of a system of materialism except the affirmative and negative copulas. These are withheld, because we cannot be supposed to believe anything inconceivable, as all ontological dogmas are. He seems to lead us on to the point of requiring our assent to a materialistic doctrine, and then lets us off on account of the infirmities of our minds; presenting materialism to our con- templation rather than to our understandings. Mr. Spencer regards the ultimate ideas of science as un- knowable ; and in a sense the meanings of the abstractest terms are unknowable, that is, are not referable to any notions more abstract, nor susceptible of sensuous apprehension or represen- tation as such. But the way to know them is to use them in mathematical formulas to express precisely what we do know. It is true that this cannot yet be done, except in the physical sciences proper, and not always with distinctness in these. It is only in astronomy and mechanical physics that these terms are used with mathematical precision. They change their meanings, or at least lose their definiteness, when we come to chemistry and physiology. 7 8 PHILOSOPHICAL DISCUSSIONS. " The indestructibility of matter," " the continuity of mo- tion," "the conservation of force," and "the correlation and equivalence of forces," are ideas which mathematical and phys- ical science has rendered familiar. Besides these, Mr. Spencer has analyzed others, descriptive of the general external char- acteristics of motion; and he continues with a development of what the Law of Evolution implies. To all the ideas which he adopts from science he adds a new sense, or rather a vague- ness, so as to make them descriptive of as much as possible. One of these ideas loses in the process so many of its original features, as well as its name, that we should not have recog- nized it as the same, but for Mr. Spencer's justification of what he regards as a change of nomenclature. He prefers "per- sistence of force" to "conservation of force," because the lat- ter " implies a conservator and an act of conserving," and be- cause " it does not imply the existence of the force before that particular manifestation of it with which we commence." Sci- ence, we are inclined to believe, will not adopt this emenda- tion, because the conservation it refers to is that whereby the special conditions of the production of any mechanical effect in nature are themselves replaced by the changes through which this effect is manifested; so that if this effect ceases to appear as a motion, it nevertheless exists in the altered antece- dents of motions, which may subsequently be developed in the course of natural changes. It is this conservation of the con- ditions of motion by the operations of nature through the strict- est observation of certain mathematical laws, that science wishes to express. The objection (if there be any) to this phrase is in the word "force." This word is used in mathematical me- chanics in three different senses, but fortunately they are distinct. They are not here fused together, as they are by Mr. Spencer, into one vague expression of what nobody in fact knows anything about. There is no danger of ambiguities aris- ing from this source in mathematics. The ideas expressed by this word are perfectly distinct and definable. The liability to ambiguity is only when we pass from mathematical formulas to sciences, in which the word has more or less of vagueness and an ontological reference. This liability is somewhat dimin- THE PHILOSOPHY OF HERBERT SPENCER. 79 ished, at least so far as distinct mathematical comprehension is concerned, by the use of the phrases, "conservation of mechan- ical effect" or "the law of power," which are now employed to express the mathematical theorem which has as one of its corollaries the doctrine that "perpetual motion" is impossible in the sense in which practical mechanics use the words. This theorem is deduced from the fundamental laws of motion, or those transcendental ideas and definitions which have received their proof or justification in their ability to clear up the confu- sions with which the movements of nature fall upon the senses and present themselves to the undisciplined understanding. The phrase "conservation of force" was adopted from mathematical mechanics into chemical physics, with reference to the question of the possibility of "perpetual motion" by means of those natural forces with which chemistry deals. The impossibility of "perpetual motion," or the fact that "in the series of natural processes there is no circuit to be found by which mechanical force can be gained without a corresponding consumption," had been demonstrated only with reference to the so-called "fixed forces" of nature, or those which depend solely on the relative distances of bodies from each other. Chemical forces are not mathematically comprehended, and are therefore utterly unknown, save in their effects, and their laws are unknown, save in the observed invariable orders of these effects. These forces are merely hypotheses, and hypoth- eses which include little or nothing that is definite or profitable to research. But mechanical forces suggested to physicists a problem perfectly clear and definite. "Are the laws of chem- ical forces also inconsistent with 'perpetual motion'?" "Are light, heat, electricity, magnetism, and the force of chemical transformations, correlated with each other, and with mechan- ical motions and forces, as these are among themselves?" Here is something tangible; and the direction which these questions have given to physical researches in recent times mark out a distinct epoch in scientific progress. Here the an- swer could not be found a priori, as a consequent of any known or presumed universal laws of nature. Experiment must establish these presumptions ; and it does so with such 80 PHILOSOPHICAL DISCUSSIONS. an overwhelming amount of evidence, that they are made the grounds of prediction, as the law of gravity was in the dis- covery of the planet Uranus. Physicists have anticipated, on the ground of the impossibility of perpetual motion, such an apparently remote fact as this, " that the freezing temperature in water depends on the pressure to which the water is sub- jected." Experiment confirms this anticipation. The processes of such researches are long and intricate, but they are perfectly precise and definite ; and it is thus that the law of the "Conservation of Force" is made of value, and not by such use as Mr. Spencer is able to make of it, if indeed his "Persistence of Force" can be regarded as having any meaning in common with it. His principle seems to us to bear a much closer resemblance to the old metaphysical " Principle of Causality," or the impossibility of any change in the quantity of existence (whatever this may mean) ; and it also seems to us to be as profitless. Having developed his Law of Evolution to maturity, he ar- rives at "Equilibration." All evolutions must have an end, and this end is "Equilibration." Then there is no longer any tendency to " a definite, coherent heterogeneity, through con- tinuous dirTerentiavtions and integrations." Life is balanced. The worlds are completed. Throughout this speculation the mechanical arguments of the Nebular Hypothesis have been the guides to Mr. Spencer's abstractions, while the doctrines of embryology have furnished the terminology. Recent developments of this hypothesis in connection with the theory of the correlations of mechanical forces and heat, have afforded him a splendid opportunity to carry out and illustrate his theories, and this opportunity Mr. Spencer has not neglected. Fully convinced of the truth of the Nebular Hypothesis, as well as of the importance of his own Law of Evolution, he reasons with the earnestness of conviction and with the blindness of zeal ; and he brings to bear upon his theories the intense interest which the recent developments of physics are calculated to awaken concerning certain problems in astronomy. The source of the sun's heat, the origins of the planets and their motions in the solar system, THE PHILOSOPHY OF HERBERT SPENCER. 81 the past and future histories of the earth and of the universe, — all these topics have an interest outside of science. They ap- peal to the story-loving, mythic instinct which willingly helps Science over her difficulties and uncertainties. It is desirable on this account to distinguish as far as possible between what is demonstrative or scientifically probable, and what is im- aginary or poetically probable, in theories on these sub- jects. To do this adequately is the work of time, patience, and science, following the methods of experimental philosophy rather than those of Mr. Spencer. We can now present only the elements of these problems, with the impressions which come from an a priori distrust of cosmological speculations. The discovery of the constant relation of mechanical effect and heat, and the determination of the measures by which this relation can be mathematically expressed in an equation, gave at once, by a simple computation with well-known astronomical data, results of the most surprising and interesting character. The mere motions of bodies, such as they have in the spaces of the solar system, and such as the sun is able to produce in bodies falling to it and in the masses of which it is com- posed through their mutual attractions, were found to repre- sent vastly greater quantities of heat than could be produced by any known chemical agency, like combustion, with the same quantity of matter of whatever kind. Here then was the long sought for origin of the sun's heat. If the motions continually produced and arrested in the contractions of the sun's mass, incident to its cooling, should only amount to what would diminish the sun's diameter by one part in twenty millions in a year, it would be sufficient to produce all the enormous amount of heat which the sun has been proved to radiate in that time. If a body falling from a height not greater than the known limits of the solar system should have the motion it would thus acquire arrested and dissipated in the form of heat in the mass of the sun, it would also produce this amount of heat, pro- vided the mass of the body be to that of the sun only as one to thirty millions. At least one-half of the energy represented by this heat would be acquired in that part of the fall between the surface of the sun and a height not greater than the dis- 82 PHILOSOPHICAL DISCUSSION'S. tance of this surface from the centre; and if the body should have fallen from the greatest supposable height, all but about one in six thousand parts of this energy would have been ac- quired within the known limits of the solar system, and all but about one in two hundred parts within the limits of the earth's orbit. To explain the origin of the sun's heat, two theories have, therefore, been advanced. One in accordance with the Nebular Hypothesis explains it as arising from the falling in upon itself of the matter which composes the mass of the sun and an arrest of this motion resulting in heat and a continuous contraction of the sun's diameter, but without any change in the sun's mass. The*other, on the evidence there is of the existence of innumerable small bodies moving in irregular and eccentric orbits through the spaces of the solar system, supposes the frequent fall of such bodies to the sun, and the arrest of their motions in its mass, as the origin of its heat. What shall decide between these two theories ? At first sight, the fact that the mass of the sun does not change so fast as the second theory appears to require, as is evinced by the fact that there is not a corresponding change in the attractive energy of the sun, and in the resultant periods of revolution in the earth and other planets, seems to refute this theory, and to decide in favor of the first. On the other hand, the second theory appeals to its foundation in independently probable evidence which the first does not possess, and to another theoretical consideration which explains away this difficulty, namely, the consideration that only one-half of the problem has yet been attended to ; for on either hypothesis we should explain, not only how the sun's heat is produced, but also what becomes of the mechanical energy which this heat repre- sents. Dr. Mayer, who advances the second or the meteoric hy- pothesis, is content to affirm that the matter of the sun is dissipated also, as well as its heat, through the agency of its heat; so that its mass remains sensibly constant. This addi- tional hypothesis has in itself about the same character which the Nebular Hypothesis possesses. So far, therefore, the two explanations are balanced. Both explain the origin of the THE PHILOSOPHY OF HERBERT SPENCER. 8$ sun's heat and the constancy of its mass by the union of facts independently probable with an hypothesis made for the pur- pose of explanation but not inconsistent with observed facts. The one theory adopts the hypothetical contraction of the sun's diameter, which observation has been unable to test, with the observed fact that the sun's mass does not increase so much as the other theory seems to require. And the other theory avoids this requirement by the hypothesis of the dis- sipation of the matter of the sun, united with the independ- ently probable fact that bodies are continually falling to the sun's surface, just as they are continually falling to that of the earth, only in vastly greater numbers. It is enough to say of the Nebular Hypothesis, that no physi- cist of repute regards it as having that degree of independent probability which warrants its use as a ground of probable pre- diction, or as affording a justification of any new or implied hy- pothesis. But the uncertainty as to which of the two mechan- ical theories of the origin of the sun's heat is true, should not for a moment be compared to the uncertainty of the Nebular Hypothesis. For it is almost certain that either one or the other is the true explanation; and, indeed, they are not essentially inconsistent with each other. Both may be true ; or rather a third theory, combining both, may have a probability superior to that of either. If it be true that the sun is a body at a mini- mum of temperature, which on account of its enormous mass and attractive energy is able, through the contractions due to its loss of heat, to make compensation for its radiations at the expense of its dimensions, then it follows that this temperature is also a maximum one, and that an increase of the total heat of the sun by the fall of bodies to it will not increase its temper- ature, but rather its dimensions; its temperature being kept uniform, much as the energies and impulsions of an engine are reduced to uniformity by the inertia of its fly-wheel and that of the bodies on the resistances of which its energies are expended. But on what are the energies of the sun expended ? What becomes of its radiations ? Mr. Spencer speaks in his vague way and in his dialect of the mechanical processes of the solar system as constituting " Evolution where there is a predomi- 84 PHILOSOPHICAL DISCUSSIONS. nant integration of Matter and disintegration of Motion." He regards the laws of change as causes of "Dissolution where there is a predominant integration of Motion and disintegra- tion of Matter." What in the language of physics does all this mean ? We suppose it means that the parts of a body or a system of bodies are brought nearer each other on the whole by a loss of internal motions, whether these be in the form of heat or of massive motions ; and that a system or a body is ex- panded on the whole by an addition to its internal motions or the relative motions of its parts. These are important mechan- ical theorems, but their deduction and extension by generaliza- tion necessitates the scholium, that all such "Evolutions" are attended by corresponding " Dissolutions." Motion is the mo- tion of something, though Mr. Spencer seems to speak of it as capable of existing by itself. Motion may grow less or cease in a body or a system without being lost from it, but in this case it is represented by an expansion of the body or the sys- tem. The motions of the solar system are continually varying, becoming greater or less according as the bodies of the system are approaching or receding from each other on the whole. But motions really lost from one body or system of bodies are taken up by others, and those which are really gained are ac- quired from others. This is so universally true, that it includes the motions of living as well as of so-called dead matter. The motions of heat and of mechanical energy in the living body are necessarily derived from the motions and antecedent special conditions of motion which are contained in the sunbeam and in the food through which the living bodies of plants and an- imals are formed. But while in these bodies, during their growths and throughout their lifetimes, there is a well-marked order and harmony in such changes, the definitions of which are the proper definitions of life, yet such an order is not nec- essarily implied in the universal laws of change. All that is necessarily implied in these is balance and ultimate compensa- tions, — compensations in times and spaces, which are wholly indefinite, and in concrete series of phenomena, which may or may not be simple orders or intelligible as wholes, but over which it is certain an elementary order reigns supreme. THE PHILOSOPHY OF HERBERT SPENCER. 85 The principle of the conservation of mechanical energy in and through the operations by which it is manifested, is the expression of this elementary order, from which, however, nothing can be deduced a pi'iori in regard to any class or con- crete series of phenomena in nature. The positions of the planets are deducible a posteriori from a sufficient number of particular facts in this concrete series, and by means of elemen- tary laws. But while such successions as life exhibits involve the law of the conservation of force, so far as they involve any changes in matter, yet no characteristic features in such suc- cessions are deducible from this law, notwithstanding Mr. Spencer's asserted demonstrations of the contrary. Life must still be studied from without. Its principle is not yet discov- ered. Concentration of matter with a transfer of its internal mo- tions to other matter, and separation of matter by motions received from without, are both exemplified in growth. Mr. Spencer calls the first " Evolution," but the growth of plants is really characterized by the second; for though there is a concentration of carbon in the tissues of the plant, yet the me- chanical operation by which this is effected is really a sepa- ration of the carbon from oxygen by the mechanical energy of the sunbeam, which, coming in from without, overcomes the forces of chemical aggregation in carbonic acid. There is here an aggregation of matter so far as mass or weight is concerned, but none so far as the chemical forces are concerned. In respect to these forces, vegetation is a dispersion of matter through an accession of forces ; and combustion or consump- tion as food in animal bodies is a dispersion of forces with a concentration of matter, though so far as mass or weight is concerned this matter is also dispersed in the form of carbonic acid gas. Dispersion and concentration are not to be mechanically measured by mere distances in space, even in the case of grav- itation; for, as we have said, a body falling from the limits of the solar system acquires on reaching the surface of the sun all but one in six thousand parts of the energy which it could acquire in falling from the height of the remotest star. The S6 PHILOSOPHICAL DISCUSSIONS. immense distances by which the stars are separated from each other are not, therefore, the representant of a much greater energy than that which the dimensions of the solar system rep- resent, though these become as nothing in respect to mere dis- tance. Gravitation is a feeble force except in close proximity, and there is some degree of probability in the speculation which regards it as really a resultant of the forces to which it seems to give rise. Whether this speculation be true or not, there is no evidence that the law of gravity is exact, or more than approximately true, or that the force of gravity subsists at all between the remotest stars. That it plays but an insig- nificant part in determining the distributions and motions of stars and systems of stars is highly probable, since these are but imperfectly accounted for, if at all, by its law. The mo- tions of the closely proximate members of binary stars are in fact the only ones in sidereal astronomy which have been brought under the law of gravity. Still it would be contrary to the postulate of science, or to any sound principle of philoso- phizing, to regard the distribution of the stars as in any abso- lute sense fortuitous ; for in this also, as in nature generally, there is that vaguely discerned order which warrants the postu- late of science, and its efforts to decipher what it has a right to presume, namely, at least an elementary order. We hold the opinion that the mechanical theory of heat, when it comes to be applied in earnest to the problems of dynamics in sidereal astronomy, will be rewarded with triumphs not inferior to those which the law of gravitation has achieved in the solar system ; and that the distribution of the stars will be accounted for, not on the hypothesis of simple attractive or repulsive forces, but by the distributions of matter and heat through the interstellar spaces, and by their actions and re- actions, not as centres of simple forces, but as the receptacles of concrete masses and motions, and as the sources of diffused motions and matters, none of which can ever be lost or de- stroyed; that their motions will be found to result principally from those of the medium of diffused materials, from which they are aggregated precipitates, and into which they are evap- orated by heat. THE PHILOSOPHY OF HERBERT SPENCER. 87 This is at present only an hypothesis, but it is not teleolog- ical in any sense of the term. The most obvious objection to it is the theory that there is u a "universal tendency in nature to the dissipation of mechanical energy," a theory well founded, nay, demonstrated,* if we only follow this energy as far as the present limits of science extend. But to a true Aristotelian this theory, so far from suggesting a dramatic denouement, such as the ultimate death of nature, only propounds new problems. What becomes of the sun's dynamic energy, and whence do the bodies come which support this wasting power ? The earth is composed of masses mechanically as well as chemically heterogeneous. The forces of chemical aggrega- tion overcome this confusion to a limited extent, through the agency of internal heat and aqueous solution, in the formation of metallic deposits and crystalline segregations, but only to a limited extent. Long persistent mechanical actions of air and water, and vegetable aggregations, produce a similar mechanical homogeneity in geological deposits. Still the materials of the earth's surface exist as if they had been thrown together with- out any determinable order, — as if the earth and similar bodies had been compounded of the materials of smaller masses fall- ing together, and gradually wrought by geological forces into the little order they present. Materials continue to arrive at the earth's surface, — in how great quantities it is at present impossible to form a trustworthy estimate. Are not all large bodies so formed ? But how are the smaller bodies formed ? The comets, which are more numerous "in the heavens than fish in the ocean," and the meteors, more numerous than the sands of the desert, — how are they formed ? Our answer is an hypothesis. They are formed by chemical and mechanical aggregation from matters diffused throughout space by the mechanical energy of the sun ; and by their fall they restore this energy. This would complete the round, of nature, but the theory is not thereby demonstrated. Scientific demon- stration is slow and painful, the work of time and patience. All that can now be presented are problems, but these are sci- entific problems. They are concerned with the details of an * By Professor William Thomson. 88 PHILOSOPHICAL DISCUSSIONS. elementary order, which science has a right to presume, and not with the abstract features of an external order, which science has no right to presume. Following the publication of his " First Principles," there ap- peared a short essay by Mr. Spencer on "The Classification of the Sciences;" to which are added his "Reasons for dissenting from the Philosophy of M. Comte." We had a little hope that here at least Mr. Spencer's reputation for philosophical analysis, and for an extensive knowledge of the sciences, would stand proof, and be confirmed by a valuable result. Instead of this, we find nothing deserving attention from any one who does not find in his "First Principles" the germs of a great philos- ophy, except bad criticism, a perverted terminology, and fanciful discriminations. Nearly all philosophers are agreed, we believe, in assigning logic and mathematics to a distinct division of the sciences, and these have with great propriety been denominated formal sciences, as distinguished from the real or material sciences. This propriety is quite independent of any metaphysical or critical theory which we may have about the origin or intrinsic character of mathematical and logical truth. Whether we regard the truths of formal science as really universal or not, their presumed universality is what determines their peculiar character and functions in science generally. But Mr. Spen- cer seems more solicitous to avoid an implication of a meta- physical doctrine, which these terms have, than to avail himself of their real scientific utility ; and he uses, instead of them, the ambiguous and otherwise objectionable terms "abstract" an>i "concrete," and is obliged, consequently, to define and defend these in the sense in which he proposes to use them. Truths that have exemplification in nearly every class of facts of which we have precise knowledge, the axioms and postulates of which are implied, indeed, in all knowledge, may relatively to all other truths be properly regarded as a priori and formal or as the moulds into which these truths are cast. It may be, as Mr. Spencer thinks, that these truths are obtained by ab- straction alone, from our experience of things; nevertheless, to make any reference in a classification to this circumstance is THE PHILOSOPHY OF HERBERT SPENCER. 89 to sacrifice the proper objects of a classification to an extrinsic object, and is also open to the objection which seems to have prevailed with him, though he makes no explicit reference to it, against the more generally received terms "formal" and "ma- terial." "Formal" implies precisely what Mr. Spencer means by wholly abstract, and "material" what he means by wholly concrete; but he uses the unqualified terms "abstract" and "concrete" in these extreme senses. He gets confused about the distinction of "abstract" and "general," and thinks M. Comte and M. Littre have confounded them. According to the most authentic usage, "abstract" and "general," though not the same, are not antithetical, as Mr. Spencer would have them to be. He says: " Abstractness means, detachment from the incidents of particular cases. Gen- erality means manifestation in numerous cases." Total de- tachment he means, for he uses "abstract" and "concrete" as exclusive contraries. In this use, however, Mr. Spencer is not alone; for the character of the process of abstraction, says Sir William Hamilton, has "been overlooked by philosophers, insomuch that they have opposed the terms concrete and ab- stract as exclusive contraries." But no philosopher before Mr. Spencer has attempted to establish any opposition between "abstract" and "general;" for though the "abstract" does not imply generality, yet generality is dependent on abstraction. " Manifestation in numerous cases" is the manifestation of what ? — we would inquire of Mr. Spencer. Of anything but what must be obtained by abstraction ? And yet he claims that his use of the words "abstract," "concrete," and "general" is the correct one. M. Littre's definition of abstractness as "sub- jective generality," does not appear to us a very happy one, but it is vastly superior to his critic's definitions. In designating by the terms "abstract," "abstract-concrete," and "concrete" the divisions of the sciences which the words "formal," "mixed," and "material" have hitherto denoted, Mr. Spencer has only confused a subject already possessed of an adequately precise nomenclature. The presumed univer- sality of mathematical and logical truth, the entirely empirical generality of merely descriptive sciences, and the union of these 9 o PHILOSOPHICAL DISCUSSIONS. kinds of truth in general physics, are properly connoted by the terms already in use. In Mr. Spencer's subdivisions of mathematics he has given a prominence to "Descriptive Geometry" which might be regarded as arising from the partiality of the civil engineer for a branch of his own art, were it not that he says : "I was ignorant of the existence of this as a separate division of mathematics, until it was described to me by Mr. Hirst, whom I have also to thank for pointing out the omission of the subdivision 'Kine- matics.' It was only when seeking to affiliate and define 'Descriptive Geometry ' that I reached the conclusion that there is a negatively-quan- titative mathematics, as well as a positively-quantitative mathematics. In explanation of the term negatively-quantitative, it will suffice to instance the proposition that certain three lines will meet in a point, as a negative- ly-quantitative proposition ; since it asserts the absence of any quantity of space between their intersections. Similarly, the assertion that certain three points will always fall in a straight line is negatively-quantitative ; since the conception of a straight line implies the negation of any lateral quantity or deviation." The propositions selected by Mr. Spencer to illustrate what he calls "Descriptive Geometry" are by no means peculiar to or characteristic of the art to which mathematicians have given this name. In the most elaborate and extensive treatises no more is claimed for this art than that it is an account in a sci- entific order of certain methods of geometrical construction, useful in engineering and architecture, but inferior in scientific extension even to trigonometry, to which Mr. Spencer does not deign to descend. It is possible that Mr. Spencer has in mind certain propositions in the " Higher Geometry " concern- ing relations of position and direction in points and lines ; but these cannot be made to stand alone or independently of di- mensional properties, and if they could, they would be as ap- propriately named "qualitative" mathematics as "negatively- quantitative." In short, this is the most flagrant application of " the principle of contraries " in classification which has ever come to our notice. If Mr. Spencer proposes to select from mathematics all positively-quantitative problems and proposi- tions for one branch, and all negatively-quantitative ones for the other, he must reconstruct, if he can, the whole science, and the question of terminology will then be a question be- tween him and his brothers in his own craft. THE PHILOSOPHY OF HERBERT SPENCER. 9 1 Having treated first in order the second part of Mr. Spencer's "First Principles," which comprises his "Laws of the Know- able," we now turn to the consideration of his doctrine of " the Unknowable," and his position before the religious world. This position has been greatly misunderstood, and Mr. Spen- cer himself has contributed much to the misunderstanding. He has appeared as a champion for what is sound in the older philosophy, and one of his avowed objects is to reconcile the truths of religion with those of science. He is anxious not to be thought a positivist, and he publishes as an appendix to his "First Principles" a response to his reviewer in the Revue des Deux Mondes, to show that he is not a positivist or a follower of M. Comte. It requires only a little thoughtful attention to the specula- tions of Mr. Spencer and M. Comte to see that they are radi- cally unlike, not only in the details of doctrine, but in their os- tensible aims. The religious world, however, though perhaps a little too trusting and a little dull of thought, has very acute feelings, and a fine sagacity in apprehending the religious drift of a system of philosophy. It began to have suspicions, but it was, nevertheless, anxious to see the truths of science recon- ciled with those of religion, and so it has continued to listen to Mr. Spencer. There can be no doubt of the earnestness and moral honesty of Mr. Spencer's writings. He is conscious of a generous pur- pose, and is actuated by the modern form of religious sentiment, — moral idealism, or a belief in the moral perfectibility of things in general. He only lacks a distinct consciousness of his exact position with reference to older forms of religious sentiment. He imagines that his philosophy can conciliate these also. This conciliation is effected, he thinks, by presenting the un- knowable as a subject of contemplation, — the abstract unknow- able, not an entity or a subject for propositions and beliefs. Beliefs about the unknowable are absurd, thinks Mr. Spencer. It is only in the existence of the unknowable as implied in the existence and limits of the knowable that we can believe, and this becomes more and more distinct as the knowable becomes more distinct in its conditions and limits. 9 2 PHILOSOPHICAL DISCUSSIONS. "Thus the consciousness of an Inscrutable Power manifested to u? through all phenomena has been growing ever clearer, and must eventu- ally be freed from its imperfections. The certainty that on the one hand such a Power exists, while on the other hand its nature transcends intui- tion and is beyond imagination, is the certainty towards which intelligence has from the first been progressing. To this conclusion science inevitably arrives as it reaches its confines ; while to this conclusion religion is ir- resistibly driven by criticism. And satisfying as it does the demands of the most rigorous logic at the same time that it gives the religious senti- ment the widest possible sphere of action, it is the conclusion we are bound to accept without reserve or qualification. "Some do indeed allege that though the Ultimate Cause of things can- not really be thought of by us as having specified attributes, it is yet in- cumbent upon us to assert these attributes. Though the forms of our consciousness are such that the Absolute cannot in any manner or degree be brought 'within them, we are nevertheless told that we must represent the Absolute to ourselves under these forms. As writes Mr. Mansel in the work from which I have already quoted largely, ' It is our duty then to think of God as personal ; and it is our duty to believe that he is infi- nite.' " That this is not the conclusion here adopted needs hardly be said. If there be any meaning in the foregoing arguments, duty requires us neither to affirm or deny personality. Our duty is to submit ourselves with all humility to the established limits of our intelligence, and not per- versely to rebel against them. Let those who can believe that there is eternal war set between our intellectual faculties and our moral obligations. I for one admit no such radical vice in the constitution of things. "This, which to most will seem an essentially irreligious position, is an essentially religious one, — nay, is //^religious one to which, as already shown, all others are but approximations." We are inclined to think, nevertheless, that the older forms of religious sentiment, instead of being satisfied with this, and accepting it in lack of a better reconciliation, will resort rather to formularies and the fine arts. Religious sentiments are es- sentially constructive. They must have propositions, or some- thing to believe, — something to give entire, free, and hearty assent to. Strings of abstract incomprehensible terms, with the copulas all left out, — nothing to believe in except our own ig- norance (however respectable this may be), — will never do. If thought cannot furnish the copulas, feeling can and will. But, we must repeat that the philosophy of Sir William Hamilton went as far in the direction of empiricism as was possible without renouncing the interests to which philosophy THE PHILOSOPHY OF HERBERT SPENCER. 93 has always been devoted. Hamilton's doctrine aimed only at this, — to show that unbelief or negative dogmatism was un- founded, and to open the way for the authority of religious feeling. Mr. Mansel, correctly apprehending the drift of Sir William Hamilton's doctrine, elaborated it still further, and supplied what was wanting to make it a religious philosophy, namely, the authority of religious feeling ; but it was the authority of the religious feelings of his own sect, of course. This move- ment, apparently in behalf of the Established Church, roused great opposition to the doctrines of Hamilton on the part of dissenting theologians. They attacked what had been before called in question, the empirical doctrines to which, while ad- mitting" and defending them theoretically, Hamilton opposed what is peculiarly his own philosophy, as a practical defense of religion. But any other sectarians were just as competent to supply the defects of Hamilton's philosophy as Mr. Mansel. They had only to advance the authority of their religious feel- ings into the vacant place. Controversy would have gone on just as before. Only the irreligious would have been excluded from the field. But the vacant place was historically preoc- cupied by Mr. Mansel, and it was thought necessary by the others to carry the whole position. Thus religious controversy blinded both the friends and the foes of religious philosophy in regard to the true scope and po- sition of Sir William Hamilton's doctrine. He has come to be regarded by both parties as the great modern champion of philosophical empiricism, whereas he only cited it against Cousin and the German rationalists, and proposed as his own contribution to philosophy that which is regarded by Mr. Spencer as a defect and an inconsistency in his philosophy. " The Conditioned," says Hamilton, "is a mean between two extremes, two inconditionates, exclusive of each other, neither of which can be con- ceived as possible, but of which, on the principles of contradiction and ex- cluded middle, one must be admitted as necessary. On this opinion, therefore, reason is shown to be weak, but not deceitful. The mind is not represented as conceiving two propositions subversive of each other as equally possible ; but only as unable to understand as possible either of two extremes, one of which, however, on the ground of their mutual 94 PHILOSOPHICAL DISCUSSIONS. repugnance, it is compelled to recognize as true. We are thus taught the salutary lesson, that the capacity of thought is not to be constituted into the measure of existence ; and are warned from recognizing the domain of our knowledge as necessarily co-extensive with the horizon of our faith. And by a wonderful revelation we are thus, in the very consciousness of our inability to conceive aught above the relative and finite, inspired with a belief in the existence of something unconditioned beyond the sphere of all comprehensible reality." Of this passage, in which Sir William Hamilton first stated his own peculiar doctrine, though less clearly than in his subse- quent writings, Mr. Spencer says : "By the laws of thought, as Sir William Hamilton has interpreted them, he finds himself forced to the conclusion, that our consciousness of the absolute is a pure negation. He nevertheless finds that there does exist in consciousness an irresistible conviction of the real 'existence of something unconditioned.' And he gets over the inconsistency by speak- ing of this conviction as a 'wonderful revelation,' 'a belief with which we are 'inspired'-; thus apparently hinting that it is supernaturally at variance with the laws of thought. [!] Mr. Mansel is betrayed into a like inconsistency," — which Mr. Spencer proceeds to point out. Strange inconsistency indeed, if it be true, between that which is mistaken by his critic as the essence of his philosophy, and that which, being the real essence, is regarded as an incon- sistency. Supposing Sir William Hamilton and Mr. Mansel are really arguing in the interests of empiricism, he tries to help them out, and supply another proof of "the relativity of all knowledge;" yet he finds in some of the statements of his friends an implication of " a grave error." He thinks they deny by implication that we can "rationally affirm the positive exis- tence of anything beyond phenomena ; " whereas what they are all along trying to prove is, that we can rationally affirm what we cannot positively conceive or construe to thought. This includes what Mr. Spencer calls "the incomplete thoughts of an indefinite consciousness," and more. It even signifies that we can and do rationally affirm not only what is incompletely thought of, but that of which we can only think the meanings, or the relations of the terms by which it is expressed. Mr. Spencer believes that we have an indefinite conscious- ness of the Absolute and of Cause, but not one which will war- THE PHILOSOPHY OF HERBERT SPENCER. 95 rant any other proposition than that which is implied in this consciousness, namely, that it is not distinct. That we can be distinctly ignorant is the highest religious truth he has to offer. In setting forth this his contribution *to religious philosophy, he characterizes the argument of his predecessors thus : "Truly to realize in thought any one of the propositions of which the argument consists, the unconditioned must be represented as posi- tive, not negative. How then can it be a legitimate conclusion from the argument, that our consciousness of it is negative? An argument, the very construction of which assigns to a certain term a certain meaning, but which ends in showing that this term has no such meaning, is simply an elaborate suicide." But really the argument of which Mr. Spencer has proved his total misapprehension is not an argument about meanings at all, but about the supposed objects of thought which the terms of the argument denote. To conceive the meaning of a proposition and to conceive the proposition itself, or to con- ceive the fact which the proposition expresses, are not the same; though in confounding them Mr. Spencer does not stand alone. The question is about the mind's ability, right, or dutv to believe what, as stated in a proposition, is stated in terms which, while their meanings are clear, cannot be united in a judgment, either by proof from what is truly known, or by intuition. If two such propositions stand in mutual contradic- tion, says Sir William Hamilton, one of them must be true, or the laws of thought are false; and he offers the alternative of absolute or philosophical scepticism, a suspension of all judg- ments, or a belief in something inconceivable. He offers it of course only formally; for a decision in favor of scepticism is self-contradictory, a judgment that all judgments are false, which ends in that painful uncertainty exhibited in the soph- ism of the liar, to which we referred in- treating of Mr. Spen- cer's Psychology. The choice between having judgments and having none is, of course, only a paradoxical mode of presenting the absurdity which cannot really be committed, but which is implied in certain confusions of thought. It was to remove these confusions by clear philosophical statements, and not to prove anything, that Hamilton's doctrine of the conditioned was propounded. 9 6 PHILOSOPHICAL DISCUSSIONS. We have now completed our survey of the principal philo- sophical works of Mr. Spencer, a writer whose pretensions aim at a system of truth which shall formulate all legitimate human knowledge, but whose performance of the part he has under- taken gives little hope of success in what yet remains to do. The number of topics which we have been led to consider in this survey illustrates the versatility of our author, and the number in regard to which we have been compelled to deny his conclusions illustrates his incompetency for the further de- velopment of his encyclopedic abstractions. LIMITS OF NATURAL SELECTION.* Few scientific theories have met with such a cordial recep- tion by the world of scientific investigators, or created in so short a time so complete a revolution in general philosophy, as the doctrine of the derivation of organic species by Natural Selection; perhaps in this respect no other can compare with it when we consider the incompleteness of the proofs on which it still relies, or the previous prejudice against the main thesis im- plied in it, the theory of the development or transmutation of species. The Newtonian theory of gravity, or Harvey's theory of the circulation of the blood, in spite of the complete and overwhelming proofs by which these were soon substantiated, were much longer in overcoming to the same degree the deeply-rooted prejudices and preconceptions opposed to them. In less than a decade the doctrine of Natural Selection had conquered the opposition of the great majority of the students of natural history, as well as of the students of general philoso- phy; and it seems likely that we shall witness the unparalleled spectacle of an all but universal reception by the scientific world of a revolutionary doctrine in the lifetime of its author ; though by the rigorous tests of scientific induction it will yet hardly be entitled to more than the rank of a very probable hypothesis. How is this singular phenomenon to be ex- plained ? Doubtless in great part by the extraordinary skill which Mr. Darwin has brought to the proof and promulgation * From the North American Review, October, 1870. 9 8 PHILOSOPHICAL DISCUSSIONS. of his views. To this, Mr. Wallace thus testifies in the Preface to his book : * "The present work will, I venture to think, prove that I both saw at the time the value and scope of the law which I had discovered, and have since been able to apply it to some purpose in a few original lines of in- vestigation. But here my claims cease. I have felt all my life, and I still feel, the most sincere satisfaction that Mr. Darwin had been at work long before me, and that it was not left for me to attempt to write 'The Origin of Species.' I have long since measured my own strength, and know well that it would be quite unequal to that task. Far abler men than myself may confess that they have not that untiring patience in ac- cumulating, and that wonderful skill in using large masses of facts of the most varied kinds, — that wide and accurate physiological knowledge, — that acuteness in devising, and skill in carrying out, experiments, and that admirable style of composition, at once clear, . persuasive, and judi- cial, — qualities which, in their harmonious combination, mark out Mr. Darwin as the man, perhaps of all men now living, best fitted for the great work he has undertaken and accomplished." But the skillful combination of inductive and deductive proofs with hypothesis, though a powerful engine of scientific discovery, must yet work upon the basis of a preceding and simpler induction. Pythagoras would never have demonstrated the "forty-seventh," if he had not had some ground of believing in it beforehand. The force and value of the preceding and simpler induction have been obscured in this case by sub- sequent investigations. And yet that more fundamental evi- dence accounts for the fact that two such skillful observers and reasoners as Mr. Wallace and Mr. Darwin arrived at the same convictions in regard to the derivation of species, in entire independence of each other, and were constrained to accept the much-abused and almost discarded "transmutation hypothesis." And both moreover reached, independently, the same explanation of the process of derivation. This was ob- viously from their similar experiences as naturalists ; from the force of the same obscure and puzzling facts which their stud- ies of the geographical distributions of animals and plants had brought to their notice, though the Malthusian doctrine of * Contributions to the Theory of Natural Selection. A Series of Essays. By Alfred Rupell Wallace, London, 1870. LIMITS OF NATURAL SELECTION. 99 population was, doubtless, the original source of their common theory. Mr. Darwin, in the Introduction to his later work on " The Variation of Animals and Plants under Domestication," attributes the beginnings of his speculations to the phenomena of the distributions of life over large continental areas, and in the islands of large archipelagoes, and especially refers to the curious phenomena of life in the Galapagos Islands in the Pa- cific Ocean. Mr. Wallace, in his first essay, originally pub- lished in 1855, four years earlier than "The Origin of Species," refers to the same class of facts, and the same special facts in regard to the Galapagos Islands, as facts which demand the transmutation hypothesis for their sufficient explanation. While then much is to be credited to the sagacity and candor of these most accomplished travelers and observers in appreciating the force of obscure and previously little studied facts, yet their theoretical discussions of the hypothesis brought forward to explain them have been of still more importance in arousing an ever-increasing activity in the same field, and in creating a new and most stimulating interest in the ex- ternal economy of life, — in the relations of living beings to the special conditions of their existence. And so the dis- cussion is no longer closet work. It is no web woven from self-consuming brains, but a vast accumulation of related facts of observation, bound together by the bond of what must still be regarded as an hypothesis, — an hypothesis, however, which has no rival with any student of nature in whose mind rever- ence does not, in some measure, neutralize the aversion of the intellect to what is arbitrary. In anticipating the general acceptance of the doctrine which Mr. Darwin and Mr. Wallace, have done so much to illustrate, we ought to except those philosophers who, from a severe, ascetic, and self-restraining temper, or from preoccupation with other researches, are disposed to regard such speculations as beyond the proper province of scientific inquiry. But to stop short in a research of " secondary causes," so long as experience or reason can suggest any derivation of laws and relations in nature which must otherwise be accepted IO o PHILOSOPHICAL DISCUSSION'S. as ultimate facts, is not agreeable to that Aristotelian type of mind which scientific culture so powerfully tends to produce. Whatever the theological tendencies of such a mind, whether ultimate facts are regarded by it as literally arbitrary, the de- crees of an absolute will, or are summarily explained by what Professor De Morgan calls " that exquisite atheism, 'the nature of things,'" it still cannot look upon the intricate system of adaptations, peculiar to the organic world (which illustrates what Cuvier calls " the principle of the conditions of existence, vulgarly called the principle oi final causes"), — it cannot look upon this as an arbitrary system, or as composed of facts in-. dependent of all ulterior facts (like the axioms of mechanics or arithmetic or geometry), so long as any explanation, not tan- tamount to arbitrariness itself, has any probability in the order of nature. This scientific instinct stops far short of an irreverent attitude of mind, though it does not permit things that claim its reverence to impede its progress. And so a class of facts, of which the organical sciences had previously made some use as instruments of scientific discovery, but which was appropri- ated especially to the reasonings of Natural. Theology, has fallen to the province of the discussions of Natural Selection, and has been wonderfully enlarged in consequence. It cannot be denied that this change has weakened the force of the ar- guments of Natural Theology ; but it is simply by way of sub- traction or by default, and not as offering any arguments op- posed to the main conclusions of theology. " Natural Selec- tion is not inconsistent with Natural Theology," in the sense of refuting the main conclusions of that science ; it only reduces to the condition of an arbitrary assumption one im- portant point in the interpretation of special adaptations in or- ganic life, namely, the assumption that in such adaptations foresight and special provision is shown, analogous to the de- signing, anticipatory imaginings and volitions in the mental actions of the higher animals, and especially in the mind of man. Upon this point the doctrine of Natural Selection assumes only such general anticipation of the wants or advantages of LIMITS OF NATURAL SELECTION. IO i an animal or plant as is implied in the laws of inheritance. That is, an animal or plant is produced adapted to the general conditions of its existence, with only such anticipations of a change or of varieties in these conditions as is implied in its general tendency to vary from the inherited type. Pardcular uses have no special causal relations to the variations that oc- cur and become of use. In other word's, Natural Selection, as an hypothesis, does not assume, and, so far as it is based on ob- servation, it affords no evidence, that any adaptation is specially anticipated in the order of nature. From this point of view, the wonderfully intricate system of special adaptations in the organic world is, at any epoch of its history, altogether retro- spective. Only so far as the past affords a type of the future, both in the organism itself and in its externa] conditions, can the conditions of existence be said to determine the adaptations of life. As thus interpreted, the doctrine of Final Causes is de- prived of the feature most obnoxious to its opponents, that abuse of the doctrine "which makes the cause to be engendered by the effect." But it is still competent to the devout mind to take a broader view of the organic world, to regard, not its sin- gle phases only, but the whole system from its first beginnings as presupposing all that it exhibits, or has exhibited, or could exhibit, of the contrivances and adaptations which may thus in one sense be said to be foreordained. In this view, however, the organical sciences lose their traditional and peculiar value to the arguments of Natural Theology, and become only a part of the universal order of nature, like the physical sciences gen- erally, in the principles of which philosophers have professed to find no sign of a divinity. But may they not, while professing to exclude the idea of God from their systems, have really in- cluded him unwittingly, as immanent in the very thought that denies, in the very systems that ignore him ? So far as Natural Theology aims to prove that the principles of utility and adaptation are all-pervasive laws in the organic world, Natural Selection is not only not inconsistent, but is iden- tical with it. But here Natural Selection pauses. It does not go on to what has been really the peculiar province of Natural 102 PHILOSOPHICAL DISCUSSIONS. Theology, to discover, or trace the analogies of organic adapta- tions to proper designs, or to the anticipations of wants and ad- vantages in the mental actions of man and the higher animals. In themselves these mental actions bear a striking resemblance to those aspects of organic life in general, which Natural Selec- tion regards; and according to the views of the experiential psy- chologist, this resemblance is not a mere analogy. In them- selves, and without reference to the external uses of these mental actions, they are the same generalized reproductions of. a past experience as those which the organic world exhibits in its laws of inheritance, and are modified by the same tenta- tive powers and processes of variation, but to a much greater degree. But here the resemblance ceases. The relations of such mental actions to the external life of an organism, in which they are truly prophetic and providential agencies, though founded themselves on the observation of a past order in experience, are entirely unique and unparalleled, so far as any assumption in the doctrine of Natural Selection, or any uroofs which it adduces are concerned. Nevertheless a greater though vaguer analogy remains. Some of the wants and adap- tations of men and animals are anticipated by their designing mental actions. Does not a like foreseeing power, ordaining and governing the whole of nature, anticipate and specially provide for some of its adaptations ? This appears to be the distinctive position in which Natural Theology now stands. We have dwelt somewhat at length on this aspect of our au- thor's subject, with reference to its bearing on his philosophical views, set forth in his concluding essay on "The Limits of Nat- ural Selection as applied to Man," in which his theological position appears to be that which we have just defined. We should like to quote many passages from the preceding essays, in illustration of the principle of utility and adaptation, in which Mr. Wallace appears at his best; but one example must suffice. "It is generally acknowledged that the best test of the truth and completeness of a theory is the power which it gives us of prevision " ; and on this ground Mr. Wallace justly claims great weight for the following inquiry into the " use of the gaudy LIMITS OF NATURAL SELECTION'. 103 colors of many caterpillars," in the essay on Mimicry, etc., p. 117: " Since this essay was first published, a very curious difficulty has been cleared up by the application of the general principle of protective coloring. Great numbers of caterpillars are so brilliantly marked and colored as to be very conspicuous even at a considerable distance, and it has been no- ticed that such caterpillars seldom hide themselves. Other species, how- ever, are green or brown, closely resembling the colors of the substances on which they feed ; while others again imitate sticks, and stretch them- selves out motionless from a twig, so as to look like one of its branches. Now, as caterpillars form so large a part of the food of birds, it was not easy to understand why any of them should have such bright colors and markings as to make them specially visible. Mr. Darwin had put the case to me as a difficulty from another point of view, for he had arrived at the conclusion that brilliant coloration in the animal kingdom is mainly due to sexual selection, and this could not have acted in the case of sexless larvae. Applying here the analogy of other insects, I reasoned, that since some caterpillars were evidently protected by their imitative coloring, and others by their spiny or hairy bodies, the bright colors of the rest must also be in some way useful to them. I further thought, that as some but- terflies and moths were greedily eaten by birds while others were distaste- ful to them, and these latter were mostly of conspicuous colors, so proba- bly these brilliantly colored caterpillars were distasteful and therefore never eaten by birds. Distastefulness alone would, however, be of little ser- vice to caterpillars, because their soft and juicy bodies are so delicate, that if seized and afterwards rejected by a bird they would almost certainly be killed. Some constant and easily perceived signal was therefore nec- essary to serve as a warning to birds never to touch these uneatable kinds, and a very gaudy and conspicuous coloring, with the habit of fully expo- sing themselves to view, becomes such a signal, being in strong contrast with the green and brown tints and retiring habits of the eatable kinds. The subject was brought by me before the Entomological Society (see Proceedings, March 4, 1867), in order that those members having oppor- tunities for making observations might do so in the following summer," etc. Extensive experiments with birds, insectivorous reptiles, and spiders, by two British naturalists, were published two years later, and fully confirmed Mr. Wallace's anticipations. His book is full of such curious matters. In a controversial essay called " Creation by Law," an an- swer to various criticisms of the doctrine of Natural Selection, Mr. Wallace is equally happy and able; and in his essay on 104 PHILOSOPHICAL DISCUSSIONS. "The Action of Natural Selection on Man," he shows a won- derful sagacity and skill in developing a new phase of his sub- ject, while meeting, as in so many other cases, obstacles and objections to the theory. It appears, both by geological evi- dence and by deductive reasonings in this essay, that the human race is singularly exempt from variation and the ac- tion of Natural Selection, so far as its merely physical quali- ties are concerned. This follows from theoretical considera- tions, since the race has come to depend mainly on its mental qualities, and since it is on these, and not on its bodily powers, that Natural Selection must act. Hence the small amount of physical differences between the earliest men of whom the re- mains have been found and the men of the present day, as com- pared to differences in other and contemporary races of mam- mals. We may generalize from this and from Mr. Darwin's observation on the comparatively extreme variability of plants, that in the scale of life there is a gradual decline in physical variability, as the organism has gathered into itself resources for meeting the exigencies of changing external conditions; and that while in the mindless and motionless plant these resources are at a mhiimum, their maximum is reached in the mind of man, which, at length, rises to a level with the total order and powers of nature, and in its scientific comprehension of nature is a summary, an epitome of the world. But the scale of life determined by the number and variety of actual resources in an organism ought to be distinguished from the rank that de- pends on a high degree of specialty in particular parts and functions, since in such respects an organism tends to be highly variable. But Mr. Wallace thinks, and argues in his concluding essay, that this marvelous being, the human mind, cannot be a prod- uct of Natural Selection; that some, at least, of the mental and moral qualities of man are beyond the jurisdiction and measure of utility; that Natural Selection has its limits, and that among the most conspicuous examples of its failure to explain the order of nature are the more prominent and char- acteristic distinctions of the human race. Some of these, ac- LIMITS OF NATURAL SELECTION. 105 cording to Mr. Wallace, are physical; not only the physical instruments of man's mental nature, his voluminous brain, his cunning hand, the structure and power of his vocal organs, but also a characteristic which appears to have no relation to his mental nature, — his nakedness. Man is distinguished from all soft and delicate skinned terrestrial mammals in having no hairy covering to protect his body. In other mammals the hair is a protection against rain, as is proved by the manner in which it is disposed, — a kind of argument, by the way, espe- cially prized by Cuvier, which has acquired great validity since Harvey's reasonings on the valves of the veins.* The backs of these animals are more especially protected in this way. But it is from the back more especially that the hairy cover- ing is' missed in the whole human race; and it is so effectually abolished as a character of the species, that it never occurs even by such reversions to ancestral types as are often exhib- ited in animal races. How could this covering have ever been * It is remarkable that our author should be so willing to attribute such a slight and unimportant character as the hair of animals, and even the lay of it, to Natural Selec- tion, and, at the same time, should regard the absence of it from the human back as be- yond the resources of natural exp'anations. We credit him, nevertheless, with the clearest appreciation, through his studies and reflections, of the extent of the action of •he law which he independently discovered; which comprises in its scope, not merely the stern necessities of mere existence, but the gentlest amenities of the most favored life. Sexual Selection, with all its obscure and subtle influences, is a type of this gen- tler action, which ranges all the way in its command of fitnesses from the hard necessi- ties of utility and warfare to the apparently useless superfluities of beauty and affection. Nay, more, a defect which, without subtracting from the attractions or any other im- portant external advantage in an animal, should simply be the source of private discom- fort to it, is certain to come under the judgments of this all-searching principle. It is a fair objection, however, sometimes made against the theory of Natural Selec- tion, that it abounds in loopholes of ingenious escape from the puzzling problems of na- ture ; and that, instead of giving real explanations of many phenomena, it simply refers them in general terms to obscure and little known, perhaps wholly inadequate causes, of which it holds omne iguohuii pro magiiijico. But this objection, though good, so far as it goes, against the theory, is not in favor of any rival hypothesis, least of all of that greatest of unknown causes, the supernatural, which is magnificent indeed in adequacy, if it be only real, but whose reality must rest forever on the negative evidence of the in- sufficiency, not only of the known, but of all possible natural explanations, and whose sufficiency even is, after all, only the counterpart or reflection of their apparent insuffi- ciencies. Hence the objection is a fair one only against certain phases of this theory, and against the tendency to rest satisfied with its imperfect explanations, or to regard them lightly as trivial defects. But to such criticisms the progress of the theory itself, in the study of nature, is a sufficient answer in general, and is a triumphant vindication of the mode of inquiry, against which such criticisms are sometimes unjustly made. 106 PHILOSOPHICAL DISCUSSIONS. injurious, or other than useful to men ? Or, if at any time in the past history of the race it was for any unknown reason in- jurious, why should not the race, or at least some part of it, have recovered from the loss and acquired anew so important a protection ? Mr. Wallace is not unmindful of Mr. Darwin's doctrine of Correlated Variation, and the explanation it affords of useless and even injurious characters in animals; but he limits his consideration of it to the supposition that the loss of hair by the race might have been a physiological consequence of correlation with some past unknown hurtful qualities. From such a loss, however, he argues, the race ought to have recov- ered. But he omits to consider the possible correlation of the absence of hair with qualities not necessarily injurious, but useful, which remain and equally distinguish the race. Many correlated variations are quite inexplicable. "Some are quite whimsical: thus cats, which are entirely white and have blue eyes, are generally deaf," and very few instances could be an- ticipated from known physiological laws, such as homological relations. There is, however, a case in point, cited by Mr. Darwin, the correlation of imperfect teeth with the nakedness of the hairless Turkish dog. If the intermediate varieties be- tween men and the man-apes had been preserved, and a regu- lar connection between the sizes of their brains, or develop- ments of the nervous system, and the amount of hair on their backs were observed, this would be as good evidence of cor- relation between these two characters as that which exists in most cases of correlation. But how in the absence of any evidence to test this or any other hypothesis, can Mr. Wal- lace presume to say that the law of Natural Selection cannot explain such a peculiarity? It may be that no valid proof is possible of any such explanation, but how is he warranted in assuming on that account some exceptional and wholly occult cause for it? There is a kind of correlation between the pres- ence of brains and the absence of hair which is not of so ob- scure a nature, and may serve to explain in part, at least, why Natural' Selection has not restored the protection of a hairy coat, however it may have been lost. Mr. Wallace himself LIMITS OF NATURAL SELECTION. 107 signalizes this correlation in the preceding essay. It is that through which art supplies to man in a thousand ways the de- ficiencies of nature, and supersedes the action of Natural Se- lection. Every savage protects his back by artificial coverings. Mr. Wallace cites this fact as a proof that the loss of hair is a defect which Natural Selection ought to remedy. But why should Natural Selection remedy what art has already cared for? In this essay Mr. Wallace seems to us to have laid aside his usual scientific caution and acuteness, and to have devoted his powers to the service of that superstitious reverence for human nature which, not content with prizing at their worth the actual qualities and acquisitions of humanity, desires to intrench them with a deep and metaphysical line of demarkation. There are, doubtless, many and very important limitations to the action of Natural Selection, which the enthusiastic stu- dent of the science ought to bear in mind ; but they belong to the application of the principle of utility to other cases as well as to that of the derivation of human nature. Mr. Wallace regards the vocal powers of the human larynx as beyond the generative action of Natural Selection, since the savage neither uses nor appreciates all its powers. But the same observation applies as well to birds, for certain species, as he says in his essay on "The Philosophy of Birds' Nests," " which have natu- rally little variety of song, are ready in confinement to learn from other species, and become much better songsters." It would not be difficult to prove that the musical capacities of the human voice involve no elementary qualities which are not involved in the cadences of speech, and in such other powers of expression as are useful at least, if not indispensable, in lan- guage. There are many consequences of the ultimate laws or uniformities of nature, through which the acquisition of one useful power will bring with it many resulting advantages, as well as limiting disadvantages, actual or possible, which the principle of utility may not have comprehended in its action. This principle necessarily presupposes a basis in an antecedent constitution of nature, in principles of fitness, and laws of cause and effect, in the origin of which it has had no agency. IC 8 PHILOSOPHICAL DISCUSSIONS. The question of the origin of this constitution, if it be a proper question, belongs to metaphysical philosophy, or, at least, to its pretensions. Strictly speaking, Natural Selection is not a cause at all, but is the mode of operation of a certain quite limited class of causes.* Natural Selection never made it come to pass, as a habit of nature, that an unsupported stone should move downwards rather than upwards. It applies to no part of inorganic nature, and is very limited even in the phenomena of organic life. In his obvious anxiety to establish for the worth of human nature the additional dignity of metaphysical isolation, Mr. Wallace maintains the extraordinary thesis that "the brain of * Though very limited in extent, this class is marked out only by the single character, that the efficient causes (of whatever nature, whether the forces of simple growth and re- production, or the agency of the human will), are yet of such a nature as to act through the principles of utility and choice. It includes in its range, therefore, developments of the simplest adaptive organic characters on one hand, and the growths of language and other human customs on the other. It has been objected that Natural Selection does not apply to the origin of languages, because language is an invention, and the work of the human will ; and it is clear, indeed, that Natural, as distinguished from Artificial, Selection is not properly the cause of language, or of the custom of speech. But to this it is sufficient to reply, that the contrast of Natural and Artificial Selections is not a con- trast of principles, but only of illustrations, and that the common principle of " the survival of the fittest" is named by Synecdoche from the broader though more obscure illustration of it. If it can be shown that the choice of a word from among many words as the name of an object or idea, or the choice of a dialect from among many varie- ties of speech, as the language of literature, is a universal process in the developments of speech and is determined by real, though special grounds of fitness, then this choice is a proper illustration of the principle of Natural Selection ; and is the more so, with reference to the name of the principle, in proportion as the process and the grounds of fitness in this choice differ from the common volitions and motives of men, or are ob- scured by the imperfections of the records of the past, or by the subtleties of the associa- tions which have determined it in the minds of the inventors and adopters of language. It is important, however, to distinguish between the origins of languages or linguistic customs, which are questions of philology, and the psychological question of the origin of language in general, or the origin in human nature of the inventions and uses of speech. Whether Natural Selection will serve to solve the latter question remains to be seen. In connection, however, with the resemblance, here noted, between the primitive, but regularly determined inventions of the mind and Natural Selection in its narrower sense, it is interesting to observe a corresponding resemblance between the theories of Free-Will and Creation, which are opposed to them. The objection that the origin of languages does not belong to the inquiries of Natural Selection, because language is an invention, and the work of Free-Will, thus appears to be parallel to the objection to Natural Selection, that it attempts to explain the work of Creation ; and both objections obviously beg the questions at issue. But both objections have force with reference to the real and proper limitations of Natural Selection, and to the antecedent conditions of its action. LIMITS OF NATURAL SELECTION I09 the savage is larger than he needs it to be " ; from which he would conclude that there is in the size of the savage's brain a special anticipation or prophecy of the civilized man, or even of the philosopher, though the inference would be far more natural, and entirely consistent with Natural Selection, that the savage has degenerated from a more advanced condition. The proofs of our author's position consist in showing that there is a very slight difference between the average size of the savage's brain and that of the European, and that even in prehistoric man the capacity of the skull approaches very near to that of the modern man, as compared to the largest capacity of anthropoid skulls. Again, the size of the brain is a measure of intellectual power, as proved by the small size of idiotic brains, and the more than average size of the brains of great men, or "those who combine acute perception with great reflective powers, strong passions, and general energy of character." By these considerations " the idea is suggested of a surplusage of pow- er, of an instrument beyond the needs of its possessor." From a rather artificial and arbitrary measure of intellectual power, the scale of marks in university examinations, as com- pared to the range of sizes in brains, Mr. Wallace concludes it to be fairly inferred, "that the savage possesses a brain capa- ble, if cultivated and developed, of performing work of a kind and degree far beyond what he ever requires it to do." But how far removed is this conclusion from the idea that the savage has more brains than he needs! Why may it not be that all that he can do with his brains beyond his needs is only incidental to the powers which are directly serviceable ? Of what significance is it that his brain is twice as great as that of the man-ape, while the philosopher only surpasses him one sixth, so long as we have no real measure of the brain power implied in the one universal characteristic of humanity, the power of language, — that is, the power to invent and use arbitrary signs ? Mr. Wallace most unaccountably overlooks the significance of what has always been regarded as the most important dis- tinction of the human race, — its rationality as shown in Ian- HO PHILOSOPHICAL DISCUSSIONS. guage. He even says that " the mental requirements of sav- ages, and the faculties actually exercised by them, are very little above those of animals." We would not call in question the accuracy of Mr. Wallace's observations of savages; but we can hardly accord equal credit to his accuracy in estimating the mental rank of their faculties. No doubt the savage mind seems very dull as compared with the sagacity shown by many animals; but a psychological analysis of the faculty of lan- guage shows that even the smallest proficiency in it might re- quire more brain power than the greatest in any other direc- tion. For this faculty implies a complete inversion of the or- dinary and natural orders of association in the mind, or such an inversion as in mere parroting would be implied by the rep- etition of the words of a sentence in an inverse order, — a most difficult feat even for a philosopher. "The power of abstract reasoning and ideal conception," which Mr. Wallace esteems as a very great advance on the savage's proficiency, is but another step in the same direction, and here, too, ce n'est que le premier pas qui coute. It seems probable enough that brain power proper, or its spontaneous and internal determinations of the perceptive faculties, should afford directly that use or command of a sign which is implied in language, and essentially consists in the power of turning back the attention from a suggested fact or idea to the suggesting ones, with reference to their use, in place of the naturally passive following and subserviency of the mind to the orders of first impressions and associations. By inverting the proportions which the latter bear to the forces of internal impressions, or to the powers of imagination in an- imals, we should have a fundamentally new order of mental actions; which, with the requisite motives to them, such as the social nature of man would afford, might go far towards defin- ing the relations, both mental and physical, of human races to the higher brute animals. Among these the most sagacious and social, though they may understand language, or follow its significations, and even by indirection acquire some of its uses, yet have no direct power of using, and no power of in- LIMITS OF NATURAL SELECTION. m But as we do not know, and have no means of knowing, what is the quantity of intellectual power, as measured by brains, which even the simplest use of language requires, how shall we be able to measure on such a scale the difference be- tween the savage and the philosopher; which consists, net so much in additional elementary faculties in the philosopher, as in a more active and persistent use of such faculties as are com- mon to both; and depends on the external inheritances of civ- ilization, rather than on the organic inheritances of the civilized man ? It is the kind of mental acquisition of which a race may be capable, rather than the amount which a trained indi- vidual may acquire, that we should suppose to be more imme- diately measured by the size of the brain; and Mr. Wallace has not shown that this kind is not serviceable to the savage. Idiots have sometimes great powers of acquisition of a certain low order of facts and ideas. Evidence upon this , point, from the relations of intellectual power to the growth of the brain in children, is complicated in the same way by the fact that pow- ers of acquisitions are with difficulty distinguished from, and are not a proper measure of, the intellectual powers, which de- pend directly on organic conditions, and are independent of an external inheritance. But Mr. Wallace follows, in his estimations of distinct men- tal faculties, the doctrines of a school of mental philosophy which multiplies the elementary faculties of the mind far be- yond any necessity. Many faculties are regarded by this school as distinct, which are probably only simple combinations or easy extensions of other faculties. The philosopher's men- tal powers are not necessarily different in their elements from those which the savage has and needs in his struggle for exist- ence, or to maintain his position in the scale of life and the re- sources on which he has come to depend. The philosopher's powers are not, it is true, the direct results of Natural Selection, or of utility ; but may they not result by the elementary laws of mental natures and external circumstances, from faculties that are useful ? If they imply faculties which are useless to the savage, we have still the natural alternative left us, which Mr. Wallace does not consider, that savages, or all the races of H2 PHILOSOPHICAL DISCUSSIONS. savages now living, are degenerate men, and not the proper representatives of the philosopher's ancestors. But this alter- native, though the natural one, does not appear to us as neces- sary; for we are not convinced that "the power of conceiving eternity and infinity, and all those purely abstract notions of form, number, and harmony, which play so large a part in the life of civilized races," are really so " entirely outside of the world of thought of the savage" as our author thinks. Are they not rather implied and virtually acquired in the powers that the savage has and needs, — his powers of inventing and using even the concrete terms of his simple language ? The fact that it does not require Natural Selection, but only the education of the individual savage, to develop in him these results, is to us a proof, not that the savage is specially provided with faculties beyond his needs, nor even that he is degenerated, but that mind itself, or elementary mental natures, in the sav- age and throughout the whole sentient world, involve and im- ply such relations between actual and potential faculties; just as the elementary laws of physics involve many apparently, or at first sight distinct and independent applications and utilities. Ought we to regard the principle of " suction," applied to the uses of life in so many and various animal organisms, as spe- cially prophetic of the mechanical invention of the pump and of similar engines? Shall we say that in the power of "suc- tion " an animal possesses faculties that he does not need ? Natural Selection cannot, it is true, be credited with such re- lations in development. But neither can they be attributed to a special providence in any intelligible sense. They belong rather to that constitution of nature, or general providence, which Natural Selection presupposes. The theories of associational psychology are so admirably adapted to the solution of problems, for which Mr. Wallace seems obliged to call in the aid of miracles, that we are sur- prised he was not led by his studies to a more careful consid- eration of them. Thus in regard to the nature of the moral sense, which Mr. Wallace defines in accordance with the intui- tional theory as "a feeling, — a sense of right and wrong, — in our nature, antecedent to, and independent of, experiences of LIMITS OF NATURAL SELECTION. 113 utility," — this sense is capable of an analysis which meets and answers very simply the difficulties he finds in it on the theory of Natural Selection. The existence of feelings of approval and disapproval, or of likings and aversions to certain classes of actions, and a sense of obligation, are eminently useful in the government of human society, even among savages. These feelings may be associated with the really useful and the really harmful classes of actions, or they may not be. Such associations are not determined simply by utility, any oftener than beliefs are by proper evidence. But utility tends to pro- duce the proper associations ; and in this, along with the in- crease of these feelings themselves, consists the moral progress of the race. Why should not a fine sense of honor and an un- compromising veracity be found, then, among savage tribes, as in certain instances cited by Mr. Wallace; since moral feelings, or the motives to the observance of rules of conduct, lie at the foundation of even the simplest human society, and rest directly on the utility of man's political nature ; and since veracity and honor are not merely 1 useful, but indispensable in many rela- tions, even in savage lives ? Besides, veracity being one of the earliest developed instincts of childhood, can hardly with propriety be regarded as an original moral instinct, since it matures much earlier than the sense of obligation, or any feel- ing of the sanctity of truth. It belongs rather to that social and intellectual part of human nature from which language it- self arises. The desire of communication, and the desire of communicating the truth, are originally identical in the ingen- uous social nature. Is not this the source of the "mystical sense of wrong," attached to untruthfulness, which is, after all, regarded by mankind at large as so venial a fault ? It needs but little early moral discipline to convert into a strong moral sentiment so natural an instinct. Deceitfulness is rather the acquired quality, so far as utility acts directly on the develop- ment of the individual, and for his advantage ; but the native instinct of veracity is founded on the more primitive utilities of society and human intercourse. Instead, then, of regarding veracity as an original moral instinct, "antecedent to, and in- dependent of, experiences of utility," it appears to us more II4 • PHILOSOPHICAL DISCUSSIONS. natural to regard it as originally an intellectual and social in- stinct, founded in the broadest and most fundamental utilities of human nature. The extension of the moral nature beyond the bounds of the necessities and utilities of society does not require a mir- acle to account for it ; since, according to the principles of the associational psychology, it follows necessarily from the elementary laws of the mind. The individual experiences of utility which attach the moral feelings to rules of conduct are more commonly those of rewards and punishments, than of the direct or natural consequences of the conduct itself; and associations thus formed come to supersede all conscious reference to rational ends, and act upon the will in the man- ner of an instinct. The uncalculating, uncompromising moral imperative is not, it is true, derived from the individual's direct experiences of its utility ; but neither does the instinct of the bee, which sacrifices its life in stinging, bear any relation to its individual advantage. Are we warranted, then, in infer- ring that the sting is useless to the bee ? Suppose that whole communities of bees should occasionally be sacrificed to their instinct of self-defense, would this prove their instinct to be in- dependent of a past or present utility, or to be prophetic of some future development of the race ? Yet such a conclusion would be exactly parallel to that which Mr. Wallace draws from the fact that savages some times deal honorably with their enemies to their own apparent disadvantage. It is a universal law of the organic world, and a necessary consequence of Nat- ural Selection, that the individual comprises in its nature chiefly what is useful to the race, and only incidentally what is useful to itself; since it is the race, and not the individual, that endures or is preserved. This contrast is the more marked in proportion as. a race exhibits a complicated polity or social form of life ; and man, even in his savage state, " is more political than any bee or ant." The doctrine of Natu- ral Selection awakens a new interest in the problems of psy- chology. Its inquiries are not limited to the origin of species. " In the distant future," says Mr. Darwin. "I see open fields for far more important researches. Psychology will be based LIMITS OF NA TURAL SELECTION. "5 7- on a new foundation. — that of the necessary acquirements of each mental power and capacity by gradation. Light will be thrown on the origin of man and his history." More light we are sure can be expected from such researches than has been discovered by Mr. Wallace, in the principles and analysis of a mystical and metaphysical psychology. The " origin of consciousness," or of sensation and thought, is relegated similarly by Mr. Wallace to the immediate agency or interposition of a metaphysical cause, as being beyond the province of secondary causes, which could act to produce it under the principle of Natural Selection. And it is doubtless true, nay, unquestionable, that sensation as a simple nature, with the most elementary- laws of its activity, does really belong to the primordial facts in that constitution of nature, which is presupposed by the principle of utility as the ground or condi- tion of the fitnesses through which the principle acts. In like manner the elements of organization, or the capacities of living matter in general, must be posited as antecedent to the mode of action which has produced in it, and through its elementary laws, such marvelous results. But if we mean by "conscious- ness" what the word is often and more properly used to ex- press, — that total and complex structure of sensibilities, thoughts, and emotions in an animal mind, which is so closely related to the animal's complex physical organization, — so far is this from being beyond the province of Natural Selection, that it affords one of the most promising fields for its future investigations.* Whatever the results of such investigations, * In further illustration of the range of the explanations afforded by the principle of Natural Selection, to which we referred in our note, page 108, we may instance an ap- plication of it to the more special psychological problem of the development of the indi- vidual mind by its own experiences, which presupposes, of course, the innate powers and mental faculties derived (whether naturally or supernaturally) from the development x>f the race. Among these native faculties of the individual mind is the power of reproducing its own pasl experiences in memory and belief; and this is, at least, analogous, as we have said, to the reproductive powers of physical organisms, and like these is in itself an unlimited, expansive power of repetition. Human beliefs, like human desires, are naturally illimitable. The generalizing instinct is native to the mind. It is not the result of habitual experiences, as is commonly supposed, but acts as well on single experiences, which are capable of producing, when unchecked, the most unbounded beliefs and ex- pectations of the future. The only checks to such unconditional natural beliefs a.reot/ier and equally unconditional and natural beliefs, or the contradictions and limiting condi- tions of experience. Here, then, is a close analogy, at least, to those fundamental facts n6 PHILOSOPHICAL DISCUSSIONS. we may rest assured that they will not solve ; will never even propound the problem peculiar to metaphysics (if it can prop- of the organic world on which the law of Natural Selection is based ; the facts, namely, of the "rapid increase of organisms," limited only by "the conditions of existence," and by competition in that "struggle for existence" which results in the "survival of the fittest." As the tendency to an unlimited increase in existing organisms is held in check only by those conditions of their existence which are chiefly comprised in the like tend- encies of other organisms to unlimited increase, and is thus maintained (so long as ex- ternal conditions remain unchanged) in an unvarying balance of life ; and as this balance adjusts itself to slowly changing external conditions, so, in the history of the individual mind, beliefs which spring spontaneously from simple and single experiences, and from a naturally unlimited tendency to generalization, are held mutually in check, and in their harmony represent the properly balanced experiences and knowledges of the mind, and by adaptive changes are kept in accordance with changing external conditions, or with the varying total results in the memory of special experiences. This mutual limitation of belief by belief, in which consists so large a part of their proper evidence, is so prominent a feature in the beliefs of the rational mind, that philosophers had failed to discover their true nature, as elementary facts, until this was pointed out by the greatest of living psy- chologists, Professor Alexander Bain. The mutual tests and checks of belief have, in- deed, always appeared to a great majority of philosophers as their only proper evidence; and beliefs themselves have appeared as purely intellectual phases of the mind. But Bain has defined them, in respect to their ultimate natures, as phases of the will ; or as the tendencies we have to act on mere experience, or to act on our simplest, most limited experiences. They are tendencies, however, which become so involved in intellectual de- velopments, and in their mutual limitations, that their ultimate results in rational beliefs have very naturally appeared to most philosophers as purely intellectual facts ; and their real genesis in experience has been generally discredited, with the exception of what are designated specially as " empirical beliefs." It may be objected that the generative process we have here described bears only a remote and fanciful analogy, and not an essential resemblance, to Natural Selection in the organic world. But to this it is, perhaps, sufficient to reply (as in the case of the origin of language), that if "the survival of the fittest" is a true expression of the law, — it is to Mr. Herbert Spencer we owe this most precise definition, — then the development of the individual mind presents a true example of it; for our knowledges and rational beliefs re- sult, truly and literally, from the survival of the fittest among our original and sponta- neous beliefs. It is only by a figure of speech, it" is true, that this "survival of the fittest" can be described as the result of a "struggle for existence " among our primitive beliefs; but this description is equally figurative as applied to Natural Selection in the organic world. The application of the principle to mental development takes for granted, as we have said, the faculties with which the individual is born, and in the human mind these include V that most efficient auxiliary, the faculty of using and inventing language. How Natu- ral Selection could have originated this is not so easy to trace, and is an almost wholly speculative question ; but if the faculty consists essentially, as we have supposed, in a preponderance of the active and spontaneous over the passive powers of the brain, effect- ing the turning-back or reflective action of the mind, while the latter simply result in the following-out or sagacious habit, we see at least that the contrast need not depend on the absolute size of the brain, but only on the proportion of the powers that depend on its quan- tity to those that depend on its quality. We should naturally suppose, therefore, that the earliest men were probably not very sagacious creatures, perhaps much less so than the present uncivilized races. But they were, most likely, very social ; even more so, perhaps, than the sagacious savage ; for there was needed a strong motive to call this complicated and difficult mental action into exercise ; and it is even now to be observed that sagacity and LIMITS OF NA TURA L SELECTION. j 1 7 erly be called a problem), the origin of sensation or simple con- sciousness, the problem par excellence of pedantic garrulity or philosophical childishness. Questions of the special physical antecedents, concomitants, and consequents of special sensa- tions will doubtless continue to be the legitimate objects of empirical researches and of important generalizations; and such researches may succeed in reducing all other facts of actual experience, all our knowledge of nature, and all our thoughts and emotions to intelligible modifications of these simple and fundamental existences; but the attempt to reduce sensation to anything but sensation is as gratuitous and as devoid of any suggestion or guidance of experience, as the attempt to reduce the axioms of the mathematical or mechanical sciences to simpler orders of universal facts. In one sense material phe- nomena, or physical objective states, are causes or effects of sensations, bearing as they do the invariable relations to them of antecedents, or concomitants, or consequents. But these are essentially empirical relations, explicable perhaps by more and more generalized empirical laws, but approaching in this way never one step nearer to an explanation of material con- ditions by mental laws, or of mental natures by the forces of matter. Matter and mind co-exist. There are no scientific principles by which either can be determined to be the cause sociability are not commonly united in high degrees even among civilized men. Growths both in the quantity and quality of the brain are, therefore, equally probable in the history of human development, with always a preponderance of the advantages which depend upon quantity. But the present superiority of the most civilized races, so far as it is independent cf any external inheritance of arts, knowledges, and institutions, would appear to depend . chiefly upon the quality of their brains, and upon characteristics belonging to their moral and emotional natures rather than the intellectual, since the intellectual acquisitions of civilization are more easily communicated by education to the savage than the refine- ments of its moral and emotional characteristics. Though all records and traces of this development are gone, and a wide gulf separates the lowest man from the highest brute animal, yet elements exist by which we may trace the succession of utilities and advan- tages that have determined the transition. The most essential are those of the social nat- ure of man, involving mutual assistance in the struggle for existence. Instrumental to these are his mental powers, developed by his social nature, and by the reflective char- acter of his brain's action into a general and common intelligence, instead of the special- ized instincts and sagacities characteristic of other animals; and from these came lan- guage, and thence all the arts, knowledges, governments, traditions, all the external in- heritances, which, reacting on his social nature, have induced the sentiments of morality, worship, and refinement; at which gazing as in a mirror he sees his past, and thinks it his future. 1 1 8 PHIL OSOPHICA L DISCUSSIONS. of the other. Still, so far as scientific evidence goes, mind ex- ists in direct and peculiar relations to a certain form of matter, the organic, which is not a different kind, though the proper- ties of no other forms are in themselves capable, so far as sci- entific observation has yet determined, of giving rise to it. The materials and the forces of organisms are both derived from other forms of matter, as well as from the organic ; but the organic form itself appears to be limited to the productive powers of matters and forces which already have this form. The transcendental doctrine of development (which is not wholly transcendental, since it is guided, at least vaguely, by the scientific principles of cause and effect, or by the continuities and uniformities of natural phenomena) assumes that in the past course of nature the forms as well as the materials and forces of organic matter had at one time a causal connection with other forms of material existence. Mental natures, and especially the simplest, or sensations, would have had, accord- ing to this assumption, a more universal relation of immediate connection than we now know with properties of the sort that we call material. Still, by the analogies of experience they cannot be regarded as having been either causes or effects of them. Our ignorances, or the as yet unexplored possibilities of nature, seem far preferable to the vagueness of this theory, which, in addition to the continuities and uniformities univer- sally exhibited in nature, assumes transcendentally, as a uni- versal first principle, the law of progressive change, or a law which is not universally exemplified by the course of nature. We say, and say truly, that a stone has no sensation, since it exhibits none of the signs that indicate the existence of sensa- tions. It is not only a purely objective existence, like every- thing else in nature, except our own individual self-consciousness, but its properties indicate to us no other than this purely ob- jective existence, unless it be the existence of God. To suppose that its properties could possibly result in a sensitive nature, not previously existing or co-existing with them, is to reason entirely beyond the guidance and analogies of experience. It is a purely gratuitous supposition, not only metaphysical or transcendental, but also materialistic ; that is, it is not only asking a foolish ques- LIMITS OF NATURAL SELECTION. 119 tion, but giving a still more foolish answer to it. In short, the metaphysical problem may be reduced to an attempt to break down the most fundamental antithesis of all experience, by de- manding to know of its terms which of them is the other. To this sort of fatuity belongs, we think, the mystical doctrine which Mr. Wallace is inclined to adopt, "that force is a product of mind" ; which means, so far as it is intelligible, that forces, or the physical antecedents and conditions of motion (appre- hended, it is true, along with motion itself, through our sensa- tions and volitions), yet bear to our mental natures the still closer relation of resemblance to the prime agency of the Will ; or it means that "all force is probably will-force." Not only does this assumed mystical resemblance, expressed by the word "will-force," contradict the fundamental antithesis of subject and object phenomena (as the word "mind-matter" would), but it fails to receive any confirmation from the law of the correlation of the physical forces. All the motions of animals, both voluntary and in voluntary,, are traceable to the efficiency of equivalent material forces in the animal's physical organiza- tion. The cycles of equivalent physical forces are complete, even when their courses lie through the voluntary actions of animals, without the introduction of conscious or mental con- ditions. The sense of effort is not a form of force. The pain- ful or pleasurable sensations that accompany the conversions of force in conscious volitions are not a consciousness of this force itself, nor even a proper measure of it. The Will is not a measurable quantity of energy, with its equivalents in terms of heat, or falling-force, or chemical affinity, or the energy of mo- tion, unless we identify it with the vital energies of the organ- ism, which are, however (unfortunately for this hypothesis), the causes of the involuntary movements of an animal, as well as of its proper volitions considered from their physical side. But Mr. Wallace is inclined to the opinion that the Will is an incident force, regulating and controlling the action of the physical forces of the vital machine, but contributing, even in this capacity, some part at least to the actual moving forces of the living frame. He says: "However delicately a machine may be constructed, with the most ex- 120 PHILOSOPHICAL DISCUSSIONS. quisitely contrived detents to release a weight or spring by the exertion of the smallest possible amount of force, some external force will always be required; so in the animal machine, however minute may be ihe changes required in the cells or fibres of the brain, to set in motion the nerve currents that loosen or excite the pent-up forces of certain muscles, some force must be required to effect those changes." And this force he supposes to be the Will. This is the most in- telligible materialism we have ever met with in the discussions of this subject. It is true that in a machine, not only the main efficient forces, but also the incident and regulating ones, are physical forces; and however small the latter may be, they are still of the same nature, and are comparable in amount with the main efficient forces. But is not this one of the most es- sential differences between a machine and a sensitive organ- ism ? Is it impossible, then, that nature has contrived an in- finitely more perfect machine than human art can invent, — machinery which involves the powers of art itself, if it be proper to call that contrivance a machine, in which the regu- lating causes are of a wholly different nature from the efficient forces? May it not be that sensations and mental conditions, generally, are regulating causes which add nothing, like the force of the hand of the engineer to the powers which he con- trols in his machine, and subtract nothing, as an automatic ap- paratus does, from such powers in the further regulation of the machine? We may not be able to understand how such reg- ulation is possible; how sensations and other mental conditions can restrain, excite, and combine the conversions of physical forces in the cycles into which they themselves do not enter; though there is a type of such regulation in the principles of theoretical mechanics, in the actions of forces which do not af- fect the quantities of the actual or potential energies of a sys- tem of moving bodies, but simply the form of the movement, as in the rod of the simple pendulum. Such regulation in the sensitive organism is more likely to be an ultimate inexplicable fact; but it is clear that even in a machine the amounts of the regulating forces bear no definite relations to the powers they control, and might, so far as these are directly concerned, be reduced to nothing as forces; and in many cases they are re- duced to a minimum of the force of friction. They must, LIMITS OF NA TURA L SELE C TWIST. 121 however, be something in amount in a machine, because they are physical, and, like all physical forces, must be derived in quantity from pre-existing forms of force. To infer from this that the Will must add something to the forces of the organism is, therefore, to assume for it a material nature. But Mr. Wallace escapes, or appears to think (as others think who hold this view) that he escapes, from complete materialism by the doctrine of the freedom of the Will. Though he makes the Will an efficient physical force, he does not allow it to be a physical effect. In other words, he regards the Will as an ab- solute source of physical energy, continually adding, though in small amounts, to the store of the forces of nature; a sort of molecular leakage of energy from an absolute source into the nervous system of animals, or, at least, of men. This, though in our opinion an unnecessary and very improbable hypothesis, is not inconceivable. It is improbable, inasmuch as it denies to the Will a character common to the physical forces with which the Will is otherwise assimilated by this theory, — the character, namely, of being an effect in measurable amount as well as a cause, or the character of belonging to cycles of changes related by invariable quantities; but as we do not re- gard the conservation of force as a necessary law of the uni- verse, we are able to comprehend Mr. Wallace's position. It is the metaphysical method of distinguishing a machine from a sensitive organism. But we do not see why Mr. Wallace is not driven by it to the dilemma of assuming free-wills for all sentient organisms; or else of assuming, with Descartes, that all but men are machines. The latter alternative would, doubtless, redound most effectively to the metaphysical digni- ty of human nature. Mr. Wallace appears to think that un- less we can attribute to the Will some efficiency or quantity of energy, its agency must be regarded as a nullity, and our appar- ent consciousness of its influence as an illusion ; but this opin- ion appears to be based on the still broader assumption, which seems to us erroneous, that all causation is reducible to the conversions of equivalent physical energies. It may be true (at least we are not prepared to dispute the assumption) that every case of real causation involves such conversions or 6 I2 2 PHILOSOPHICAL DISCUSSIONS. changes in forms of energy, or that every effect involves changes of position and motion. Nevertheless, every case of real causation may still involve also another mode of causation. A much simpler conception than our author's theory, and one that seems to us far more probable is that the phenomena of conscious volition involve in themselves no proper efficiencies or forces coming under the law of the conservation of force, but are rather natural types of causes, purely and absolutely regulative, which add nothing to,' and subtract nothing from, the quantities of natural forces. No doubt there is in the actions of the nervous system a much closer resemblance than this to a machine. No doubt it is automatically regulated, as well as moved, by physical forces ; but this is probably just in proportion as its agency — as in our habits and instincts — is removed from our con- scious control. All this machinery is below, beyond, ex- ternal, or foreign to our consciousness. The profoundest, most attentive introspection gains not a glimpse of its activity, nor do we ever dream of its existence; but both by the laws of its operations, and by the means through which we become aware of its existence, it stands in the broadest, most funda- mental contrast to our mental natures ; and these, so far from furnishing a type of physical efficiency in our conscious voli- tions, seem to us rather, in accordance with their general con- trast with material phenomena, to afford a type of purely reg- ulative causes, or of an absolutely forceless and unresisted control and regulation of those forces of nature which are comprised in the powers of organic life. Perhaps a still higher type of such regulation is to be found in those "laws of nature," which, without adding to, or subtracting from, the real forces of nature, determine the order of their conversions by "fixed, stated, or settled" rules of succession; and these may govern also, and probably do govern, the successions of our mental or self-conscious states, both in themselves and in their relations to material conditions. Simple, absolute, inva- riable rules of succession in phenomena, both physical and mental, constitute the most abstract conception we can have of causal relations ; but they appear under two chief classes, the LIMITS OF NATURAL SELECTION. 123 physical laws which determine the possible relations of the forms of force, and those which are also concerned in the still further determination of its actual orders of succession, or which, by their combinations in the intricate web of uniformities in nature, both mental and physical, determine the events in particular that in relation to the laws of force are only deter- mined in general. The proper laws of force, or of the con- versions of energy, are concerned exclusively with relations in space. Relations in time are governed by the other class of laws. Thus, in the abstract theory of the pendulum, the phenomena of force involved are limited simply to the vertical rise and fall of the weight, upon which alone the amounts of its motions depend. The times of its vibrations are deter- mined by the regulating length of the rod, which in theory adds nothing to, and subtracts nothing from, the efficient mutually convertible forces of motion and gravity. What is here assumed in theory to be true, we assume to be actually and absolutely true of mental agencies. But it may be said, and it often is said, " that this theory of the Will's agency is directly contradicted in both its features by consciousness; that we are immediately conscious both of energy and freedom in willing." There is much in our voli- tional consciousness to give countenance to this contradiction ; but it is only such as dreams give to contradictions of rational experience. The words " force," " energy," " effort," " resist- ance," " conflict," all point to states of feeling in our volitional consciousness which seem to a superficial observation to be true intuitions of spontaneous self-originated causes ; and it is only when these states of feeling are tested by the scientific definitions and the objective measure of forces, and by the orders of the conversions of force, that they are found to be only vague, subjective accompaniments, instead of distinct ob- jective apprehensions or perceptions of what "force" signifies in science. Such tests prove them to be like the complement- ary or subjective colors of vision. In one sense they are in- tuitions of force, our only intuitions of it (as the aspects of nature are our only intuitions of the system of the world) ; but they are not true perceptions, since they do not afford, each 124 PHILOSOPHICAL DISCUSSIONS. feeling in itself, definite and invariable indications of force as an objective existence, or as affecting all minds alike. Even the sense of weight is no proper measure of weight as an ele- ment of force ; and the muscular effort of lifting is only a vague and variable perception of this conversion of force, and does not afford even a hint of the great law of the conserva- tion and convertibility of forces, but, on the contrary, seems to contradict it. The muscular feeling of resistance to motion or to a change of motion is an equally vague measure of inertia. Indeed, the feelings of weight and resistance, which are often regarded as intuitions of gravity and inertia, are insusceptible of precise measurement or numerical comparison; and though capable of being trained to some degree of precision in esti- mating what is properly measured by other means, they could never have revealed through their unaided indications the law of the fixed and universal proportionality of these two forces. The feeling of effort itself (more or less intense, and more or less painful, according to circumstances, which are quite irrel- evant to its apparent effect) appears by the testimony of con- sciousness to be the immediate cause of the work which is done, — work really done by forces in the vital organism, which only the most recondite researches of science have dis- closed. But if this much-vaunted authority of immediate con- sciousness so blunders in even the simplest cases, how can our author or any judicious thinker trust its unconfirmed, unsup- ported testimony in regard to the agency of the Will ? Is it not like trusting the testimony of the senses as to the immo- bility of the earth ? . * With hardly a point, therefore, of Mr. Wallace's concluding essay are we able to agree; and this impresses us the more, since we find nothing in the rest of his book which appears to us to call for serious criticism, but many things, on the con- trary, which command our most cordial admiration. We ac- count for it by the supposition that his metaphysical views, carefully excluded from his scientific work, are the results of an earlier and less severe training than that which has secured to us his valuable positive contributions to the theory of Nat- ural Selection. Mr. Wallace himself is fully aware of this con- LIMITS OF NA TURAL SELECTION. ™5 trast, and anticipates a scornful rejection of his theory by many who in other respects agree with him. The doctrines of the special and prophetic providences and decrees of God, and of the metaphysical isolation of human nature, are based, after all, on barbaric conceptions of dignity, which are restricted in their application by every step forward in the progress of science. And the sense of security they give us of the most sacred things is more than replaced by the ever-growing sense of the universality of inviolable laws, — laws that underlie our sentiments and desires, as well as all that these can rationally regard in the outer world. It is un- fortunate that the prepossessions of religious sentiment in favor of metaphysical theories should make the progress of science always seem like an indignity to religion, or a detraction from what is held as most sacred; yet the responsibility for this be- longs neither to the progress of science nor to true religious sentiment, but to a false conservatism, an irrational respect for the ideas and motives of a philosophy which finds it more and more difficult with every advance of knowledge to reconcile its assumptions with facts of observation. THE GENESIS OF SPECIES* ♦ It is now, nearly twelve years since the discussion of that "mystery of mysteries," the origin of species, was re-opened by the publication of the first edition of Mr. Darwin's most re- markable work. Again and again in the history of scientific debate this question had been discussed, and, after exciting a short-lived interest, had been condemned by cautious and con- servative thinkers to the limbo of insoluble problems or to the realm of religious mystery. They had, therefore, sufficient grounds, a priori, for anticipating that a similar fate would attend this new revival of the question, and that, in a few- years, no more would be heard of the matter; that the same condemnation awaited this movement which had overwhelmed the venturesome speculations of Lamarck and of the author of the " Vestiges of Creation." This not unnatural anticipation has been, however, most signally disappointed. But what can we say has really been accomplished by this debate ; and what reasons have we for believing that the judgment of conservative thinkers will not, in the main, be proved right after all, though present indications are against them? One permanent consequence, at least, will remain, in the great additions to our knowledge of natural history, and of general physiology, or theoretical biology, which the discus- sion has produced; though the greater part of this positive contribution to science is still to be credited directly to Mr. Darwin's works, and even to his original researches. But, besides this, an advantage has been gained which cannot be too highly estimated. ( Orthodoxy has been won over to the * From the North American Review, July, 1871. / THE GENESIS OF SPECIES. 127 doctrine of evolution. In asserting this result, however, we are obliged to make what will appear to many persons impor- tant qualifications and explanations. We do not mean that the heads of leading religious bodies, even in the most enlight- ened communities, are yet willing to withdraw the dogma that the origin of species is a special religous mystery, or even to assent to the hypothesis of evolution as a legitimate question for scientific inquiry. We mean only, that many eminent stu- dents of science, who claim to be orthodox, and who are cer- tainly actuated as much by a spirit of reverence as by scientific inquisitiveness, have found means of reconciling the general doctrine of evolution with the dogmas they regard as essential to religion. Even to those whose interest in the question is mainly scientific this result is a welcome one, as opening the way for a freer discussion of subordinate questions, less tram- meled by the religious prejudices which have so often been serious obstacles to the progress of scientific researches. But again, in congratulating ourselves on this result, we are obliged to limit it to the doctrine of evolution in its most gen- eral form, the theory common to Lamarck's zoological philos- ophy, to the views of the author of the " Vestiges of Creation," to the general conclusions of Mr. Darwin's and Mr. Wallace's theory of Natural Selection, to Mr. Spencer's general doctrine of evolution, and to a number of minor explanations of the processes by which races of animals and plants have been de- rived by descent from different ancestral forms. What is no longer regarded with suspicion as secretly hostile to religious beliefs by many truly religious thinkers is that which is denoted in common by the various names "transmutation," "develop- ment," "derivation," "evolution," and "descent with modifi- cation." These terms are synonymous in their primary and general signification, but refer secondarily to various hypoth- eses of the processes of derivation. But there is a choice among them on historical grounds, and with reference to as- sociations, which are of some importance from a theological point of view. "Transmutation" and "development" are under ban. "Derivation" is, perhaps, the most innocent word; though "evolution" will probably prevail, since, spite I2 8 PHILOSOPHICAL DISCUSSIONS. of its etymological implication, it has lately become most' acceptable, not only to the theological critics of the theory,, but to its scientific advocates; although, from the neutral ground of experimental science, " descent with modification " is the most pertinent and least exceptionable name. While the general doctrine of evolution has thus been suc- cessfully redeemed from theological condemnation, this is not yet true of the subordinate hypothesis of Natural Selection, to the partial success of which this change of opinion is, in great measure, due. It is, at first sight, a paradox that the views most peculiar to the eminent naturalist, whose work has been chiefly instrumental in effecting this change of opinion, should still be rejected or regarded with suspicion by those who have nevertheless been led by him to adopt the general hypothesis, - — an hypothesis which his explanations have done so much to render credible. It would seem, at first sight, that Mr. Dar- win has won a victory, not for himself, but for Lamarck. Transmutation, it would seem, has been accepted, but Natural Selection, its explanation, is still rejected by many converts to the general theory, both on religious and scientific grounds. But too much weight might easily be attributed to the deduct- ive or explanatory part of the evidence, on which the doctrine of evolution has come to rest. In the half-century preceding the publication of the "Origin of Species," inductive evidence on the subject had accumulated, greatly outweighing all that was previously known; and the "Origin of Species" is not less remarkable as a compend and discussion of this evidence than for the ingenuity of its explanations. It is not, therefore, to what is now known as " Darwinism " that the prevalence of the doctrine of evolution is to be attributed, at least directly. Still, most of this effect is due to Mr. Darwin's work, and something undoubtedly to the indirect influence of reasonings that are regarded with distrust by those who accept their con- clusions ; for opinions are contagious, even where their reasons are resisted. The most effective general criticism of the theory of Natural Selection which has yet appeared, and, at the same time, one which is likely to exert great influence in overcoming the re- THE GENESIS OF SPECIES. 129 maining prejudice against the general doctrine of evolution, is the work of Mr. St. George Mivart " On the Genesis of Species." Though the work falls short of what we might have expected from an author of Mr. Mivart's attainments as a naturalist, yet his position before the religious world, and his unquestionable familiarity with the theological bearings of his subject, will undoubtedly gain for him and for the doctrine of evolution a hearing and a credit, which might be denied to the mere student of science. His work is mainly a critique of "Darwinism"; that is, of the theories peculiar to Mr. Darwin and the " Darwinians," as distinguished from the believers in the general doctrine of evolution which our author accepts. He also puts forward an hypothesis in opposition to Mr. Dar- win's doctrine of the predominant influence of Natural Selec- tion in the generation of organic species, and their relation to the conditions of their existence. On this hypothesis, called "Specific Genesis," an organism, though at any one time a fixed and determinate species, approximately adapted to sur- rounding conditions of existence, is potentially, and by innate potential combinations of organs and faculties, adapted to many other conditions of existence. It passes, according to the hypothesis, from one form to another of specific "mani- festation," abruptly and discontinuously in conformity to the emergencies of its outward life ; but in any condition to which it is tolerably adapted it retains a stable form, subject to varia- tion only within determinate limits, like oscillations in a stable equilibrium. For this conception our author is indebted to Mr. Galton, w 7 ho, in his work on " Hereditary Genius," "com- pares the development of species with a many-faceted spheroid tumbling over from one facet or stable equilibrium to another. The existence of internal conditions in animals," Mr. Mivart adds (p. in), "corresponding with such facets is denied by pure Darwinians, but it is contended in this work that some- thing may also be said for their existence." There are many facts of variation, numerous cases of abrupt changes in individuals both of natural and domesticated species, which, of course, no Darwinian or physiologist denies, and of which Natural Selection professes to offer no direct explanation. I3 o PHILOSOPHICAL DISCUSSIONS. The causes of these phenomena, and their relations to external conditions of existence, are matters quite independent of the principle of Natural Selection, except so far as they may di- rectly affect the animal's or plant's well-being, with the origin of which this principle is alone concerned. General physi- ology has classified some of these sudden variations under such names as "reversion" and "atavism," or returns more or less complete to ancestral forms. Others have been con- nected together under the law of "correlated or concomitant variations," changes that, when they take place, though not known to be physically dependent on each other, yet usually or often occur together. Some cases of this law have been re- ferred to the higher, more fundamental laws of homological variations, or variations occurring together on account of the relationships of homology, or due to similarities and physical relations between parts of organisms, in tissues, organic con- nections, and modes of growth. Other variations are explained by the laws and causes that determine monstrous growths. Others again are quite inexplicable as yet, or cannot yet be referred to any general law or any known antecedents. These comprise, indeed, the most common cases. The almost uni- versal prevalence of well-marked phenomena of variation in species, the absolutely universal fact that no two individual organisms are exactly alike, and that the description of a species is necessarily abstract and in many respects by means of averages, — these facts have received no particular expla- nations, and might indeed be taken as ultimate facts or highest laws in themselves, were it not that in biological speculations such an assumption would be likely to be misunderstood, as denying the existence of any real determining causes and more ultimate laws, as well as denying any known antecedents or regularities in such phenomena. No physical naturalist would for a moment be liable to such a misunderstanding, but would, on the contrary, be more likely to be off his guard against the possibility of it in minds otherwise trained and habituated to a different kind of studies. Mr. Darwin has undoubtedly erred in this respect. He has not in his works repeated with suffi- cient frequency his faith in the universality of the law of THE GENESIS OF SPECIES. 131 causation, in the phenomena of general physiology or theoret- ical biology, as well as in all the rest of physical nature. He has not said often enough, it would appear, that in referring any effect to "accident," he only means that its causes are like particular phases of the weather, or like innumerable phenom- ena in the concrete course of nature generally, which are quite beyond the power of finite minds to anticipate or to account for in detail, though none the less really determinate or due to regular causes. That he has committed this error appears from the fact that his critic, Mr. Mivart, has made the mis- take, which nullifies nearly the whole of his criticism, of sup- posing that "the theory of Natural Selection may (though it need not) be taken in such a way as to lead men to regard the present organic world as formed, so to speak, accidentally, beautiful and wonderful as is confessedly the hap-hazard re- sult" (p. 33). Mr. Mivart, like many another writer, seems to forget the age of the world in which he lives and for which he writes, — the age of " experimental philosophy," the very stand- point of which, its fundamental assumption, is the universality of physical causation. This is so_ familiar to minds bred in physical studies, that they rarely imagine that they may be mistaken for disciples of Democritus, or for believers in " the fortuitous concourse of atoms," in the sense, at least, which theology has attached to this phrase. If they assent to the truth that may have been meant by the phrase, they would not for a moment suppose that the atoms move fortuitously, but only that their conjunctions, constituting the actual concrete orders of events, could not be anticipated except by a knowl- edge of the natures and regular histories of each and all of them, — such knowledge as belongs only to omniscience. The very hope of experimental philosophy, its expectation of con- structing the sciences into a true philosophy of nature, is based on the induction, or, if you please, the a priori presumption, that physical causation is universal; that the constitution of nature is written in its actual manifestations, and needs only to be deciphered by experimental and inductive research; that it is not a latent invisible writing, to be brought out by the magic of mental anticipation or metaphysical meditation. Or, as 132 PHILOSOPHICAL DLSCUSSLONS. Bacon said, it is hot by the "anticipations of the mind," but by the "interpretation of nature," that natural philosophy is to be constituted; and this is to presume that the order of na- ture is decipherable, or that causation is everywhere either manifest or hidden, but never absent. Mr. Mivart does not wholly reject the process of Natural Selection, or disallow it as a real cause in nature, but he re- duces it to "a subordinate role" in his view of the derivation of species. It serves to perfect the imperfect adaptations, and to meet within certain limits unfavorable changes in the condi- tions of existence. The "accidents" which Natural Selection acts upon are allowed to serve in a subordinate capacity and in subjection to a foreordained, particular, divine order, or to act like other agencies dependent on an evil principle, which are compelled to turn evil into good. Indeed, the only differ- ence on purely scientific grounds, and irrespective of theological considerations, between Mr. Mivart's views and Mr. Darwin's is. in regard to the extent to which the process of Natural Selec- tion has been effective in the modifications of species. Mr. Darwin himself, from the very nature of the process, has never supposed for it, as a cause, any other than a co-ordinate place among other causes of change, though he attributes to it a su- perintendent, directive, and controlling agency among them. The student of the theory would gather quite a different im- pression of the theory from Mr. Mivart's account of it, which attributes to "Darwinians" the absurd conception of this cause as acting "alone" to produce the changes and stabilities of species ; whereas, from the very nature of the process, other causes of change, whether of a known or as yet unknown nat- ure, are presupposed by it. Even Mr. Galton's hypothet- ical "facets," or internal conditions of abrupt changes and successions of stable equilibriums, might be among these causes, if there were any good inductive grounds for sup- posing their existence. Reversional and correlated variations are, indeed, due to such internal conditions and to laws of inheritance, which have been ascertained inductively as at least laws of phenomena, but of which the causes, or the ante- cedent conditions in the organism, are unknown. Mr Dar- • THE GENESIS OF SPECIES. I33 win continually refers to variations as arising from unknown causes, but these are always such, so far as observation can determine their relations to the organism's conditions of exist- ence, that they are far from accounting for, or bearing any re- lations to, the adaptive characters of the organism. It is solely upon and with reference to such adaptive characters that the process of Natural Selection has any agency, or could be supposed to be effective. If Mr. Mivart had cited anywhere in his book, as he has not, even a single instance of sudden variation in a whole race, either in a state of nature or under domestication, which is not referable by known physiological laws to the past history of the race on the theory of evolution, and had further shown that such a variation was an adaptive one, he might have weakened the arguments for the agency and extent of the process of Natural Selection. As it is, he has left them quite intact. The only direct proofs which he adduces for his theory that adaptive as well as other combinations proceed from innate predeterminations wholly within the organism, are drawn from, or rather assumed in, a supposed analogy of the specific forms in organisms to those of crystals. As under different circum- stances or in different media the same chemical substances or constituent substances assume different and distinct crystalline forms, so, he supposes, organisms are distinct manifestations of typical forms, one after another of which will appear under various external conditions. He quotes from Mr. J. J. Mur- phy's "Habit and Intelligence," that, "it needs no proof that in the case of spheres and crystals, the forms and structures are the effect and not the cause of the formative principle. At- traction, whether gravitative or capillary, produces the spher- ical form ; the spherical form does not produce attraction. And. crystalline polarities produce crystalline structure and form ; crystalline structure and form do not produce polarities." And, by analogy, Mr. Murphy and our author infer that innate vital forces always produce specific vital forms, and that the vital forms themselves, or " accidental " variations of them, cannot modify the types of action in vital force. Now, al- though Mr. Murphy's propositions may need no proof, they I34 PHILOSOPHICAL DISCUSSIONS. will bear correction ; and, clear as they appear to be, a better interpretation of the physical facts is needed for the purposes of tracing out analogy and avoiding paralogism. Strange as it may seem, Mr. Murphy's clear antitheses are not even partially true. No abstraction ever produced any other abstraction, much less a concrete thing. The abstract laws of attraction never produced any body, spherical or polyhedral. It was actual forces acting in definite ways that made the sphere or crystal ; and the sizes, particular shapes, and positions of these bodies determined in part the action of these actual forces. It is the resultants of many actual attractions, dependent in turn on the actual products, that determine the spherical or crystal- line forms. Moreover, in the case of crystals, neither these forces nor the abstract law of their action in producing definite angles reside in the finished bodies, but in the properties of the surrounding media, portions of whose constituents are changed into crystals, according to these properties and to other conditioning circumstances. So far as these bodies have any innate principle in them concerned in their own produc- tion, it is manifested in determining, not their general agree- ments, but their particular differences in sizes, shapes, and positions. The particular position of a crystal that grows from some fixed base or nucleus, and the particular directions of its faces, may, perhaps, be said to be innate ; that is, they were determined at the beginning of the particular crystal's growth. Finding, therefore, what Mr. Murphy and Mr. Mivart suppose to be innate to be really in the outward conditions of the crys- tal's growth, and what they would suppose to be superinduced to be all that is innate in it, we have really found the contrast in place of an analogy between a crystal and an organism. For, in organisms, no doubt, and as we may be readily con- vinced without resort to analogy, there is a great deal that is really innate, or dependent on actions in the organism, which diversities of external conditions modify very little, or affect at least in a very indeterminate manner, so far as observation has yet ascertained. External conditions are, nevertheless, essen- tial factors in development, as well as in mere increase or growth. No animal or plant is developed, nor do its develop- THE GENESIS OF SPECIES. 135 ments acquire any growth without very special external condi- tions. These are quite as essential to the production of an organism as a crystalline nucleus and fluid material are to the growth and particular form of a crystal ; and as the general resemblances of the crystals of any species, the agreements in their angles, are results of the physical properties of their food and other surrounding conditions of their growth, so the gen- eral resemblances of animals or plants of any species, their agreements in specific characters, are doubtless due, in the main, to the properties of what is innate in them, yet not to any abstraction. This is sufficiently conspicuous to "need no proof," and is denied by no Darwinian. The analogy is so close indeed between the internal determinations of growth in an organism and the external ones of crystals, that Mr. Darwin was led by it to invent his "provisional hypothesis of Pangen- esis," or theory of gemmular reproduction. The gemmules in this theory being the perfect analogues of the hypothetical atoms of the chemical substances that are supposed to arrange themselves in crystalline forms, the theory rather gives prob- ability to the chemical theory of atoms than borrows any from it. But we shall recur to this theory of Pangenesis further on. General physiology, or physical and theoretical biology, are sciences in which, through the study of the laws of inheritance, and the direct and indirect effect of external conditions, we must arrive, if in any way, at a more and more definite knowl- edge of the causes of specific manifestations ; and this is the end to which Mr. Darwin's labors have been directed, and have par- tially accomplished. Every step he has taken has been in strict conformity to the principles of method which the examples of inductive and experimental science have established. A stricter observance of these by Mr. Murphy and our author might have saved them from the mistake we have noticed, and from many others,— the "realism" of ascribing efficacy to an abstraction, making attraction and polarity produce structures and forms independently of the products and of the concrete matters and forces in them. A similar "realism" vitiates nearly all specu- lations in theoretical biology, which are not designedly, or even instinctively, as in Mr. Darwin's work, made to conform to the 136 PHILOSOPHICAL DISCUSSIONS. rigorous rules of experimental philosophy. These require us to assume no causes that are not true or phenomenally known, and known in some other way than in the effect to be explained; and to prove the sufficiency of those we do assume in some other way than by putting an abstract name or description of an effect for its cause, like using the words "attraction" and "polarity" to account for things the matters of which have come together in a definite form. It may seem strange to many readers to be told that Mr. Darwin, the most consummate speculative genius of our times, is no more a maker of hypoth- eses than Newton was, who, unable to discover the cause of the properties of gravitation, wrote the often-quoted but much misunderstood words, " Hypotheses non Jingo." "For," he adds, "whatever is not deduced from the phenomena is to be called an hypothesis; and hypotheses, whether metaphysical or physical, whether of occult qualities or mechanical, have no place in experimental philosophy. In this philosophy particular propositions are inferred from the phenomena, and afterwards rendered general by induction. Thus it was that the impen- etrability, the mobility, and the impulsive force of bodies, and the laws of motion and gravitation, were discovered. And to us it is enough that gravity does really exist and act according to the laws which we have explained, and abundantly serves to account for all the motions of the celestial bodies and of our sea." Thus, also, it is that the variability of organisms and the known laws of variation and inheritance, and of the influ- ences of external conditions, and the law of Natural Selection, have been discovered. And though it is not enough that vari- ability and selection do really exist and act according to laws which Mr. Darwin has explained (since the limits of their action and efficiency are still to be ascertained), yet it is enough for the present that Darwinians do not rest, like their opponents, contented with framing what Newton would have called, if he had lived after Kant, "transcendental hypotheses" which have no place in experimental philosophy. It may be said that Mr. Darwin has invented the hypothesis of Pangenesis, against the rules of this philosophy; but so also did Newton invent the corpuscular theory of light, with a similar purpose and utility. THE GENESIS OF SPECIES. 137 In determining the limits of the action of Natural Selection, and its sufficiency within these limits, the same demonstrative adequacy should not, for obvious reasons, be demanded as con- ditions of assenting to its highly probable truth, that Newton proved for his speculation. For the facts for this investigation are hopelessly wanting. Astronomy presents the anomaly, among the physical sciences, of being the only science that deals in the concrete with a few naturally isolated causes, which are separated from all other lines of causation in a way that in other physical sciences can only be imitated in the care- fully guarded experiments of physical and chemical laboratories. The study of animals and plants under domestication is, in- deed, a similar mode of isolating with a view to ascertaining the physical laws of life by inductive investigations. But the theory of Natural Selection, in its actual application to the phenomena of life and the origin of species, should not be compared to the theory of gravitation in astronomy, nor to the principles of physical science as they appear in the natures that are shut in by the experimental resources of the labora- tory, but rather to these principles as they are actually work- ing, and have been working, in the concrete courses of outward nature, in meteorology and physical geology. Still better, perhaps, at least for the purposes of illustration, we may compare the principle of Natural Selection to the fundamental laws of political economy, demonstrated and actually at work in the production of the values and the prices in the market of the wealth which human needs and efforts demand and supply. Who can tell from these principles what the market will be next week, or account for its prices of last week, even by the most ingenious use of hypotheses to supply the missing evidence ? The empirical economist and statistician imagines that he can discover some other principles at work, some pre- determined regularity in the market, some ''innate" principles in it, to which the general laws of political economy are subor- dinated ; and speculating on them, might risk his own wealth in trade, as the speculative "vitalist" might, if anything could be staked on a transcendental hypothesis. In the same way the empirical weather-philosopher thinks he can discern regu- 138 PHILOSOPHICAL DISCUSSIONS. larities in the weather, which the known principles of mechan- ical and chemical physics will not account for, and to which they are subordinate. This arises chiefly from his want of imagination, of a clear mental grasp of these principles, and of an adequate knowledge of the resources of legitimate hypothesis to supply the place of the unknown incidental causes through which these principles act. Such are also the sources of most of the difficulties which Mr. Mivart has found in the application of the theory of Natural Selection. His work is chiefly taken up with these difficulties. He does not so much insist on the probability of his own transcendental hypothesis, as endeavor to make way for it by discrediting the sufficiency of its rival; as if this could serve his purpose; as if experimental philosophy itself, without aid from " Darwin- ism," would not reject his metaphysical, occult, transcendental hypothesis of a specially predetermined and absolute fixity of species, — an hypothesis which multiplies species in an organ- ism to meet emergencies, — the emergencies of theory, — much as the epicycles of Ptolemy had to be multiplied in the heav- ens. Ptolemy himself had the sagacity to believe that his was only a mathematical theory, a mode of representation, not a theory of causation ; and to prize it only as representative of the facts of observation, or as "saving the appearances/' Mr. Mivart's theory, on the other hand, is put forward as a theory of causation, not to save appearances, but to justify the hasty conclusion that they are real; the appearances, namely, of complete temporary fixity, alternating with abrupt changes, in the forms of life which are exhibited by the scanty records of geology and in present apparently unchanging natural species. Before proceeding to a special consideration of Mr. Mivart's difficulties on the theory of Natural Selection, we will quote from Mr. Darwin's latest work, "The Descent of Man," his latest views of the extent of the action of this principle and its relations to the general theory of evolution. He says (Chapter IV): "Thus a very large yet undefined extension may safely be given to the direct and indirect results of Natural Selection ; but I now admit, after reading the essay by Nageli on plants, and the remarks by various authors THE GENESIS OF SPECIES. 139 with respect to animals, more especially those recently made by Professor Broca, that in the earlier editions of my 'Origin of Species' I probably attributed too much to the action of Natural Selection, or the survival of the fittest. I have altered the fifth edition of the 'Origin' [the edition which Mr. Mivart reviews in his work] so as to confine my remarks to adaptive changes of structure. I had not formerly sufficiently considered the existence of many structures which appear to be, as far as we can judge, neither beneficial nor injurious; and this I believe to be one of the greatest oversights as yet detected in my work. I may be permitted to say, as some excuse, that I had two distinct objects in view: firstly, to show that species had not been separately created; and secondly, that Natural Selection had been the chief agent of change, though largely aided by the inherited effects of habit, and slightly by the direct action of the surrounding conditions. Nevertheless, I was not able to annul the influence of my former belief, then widely prevalent, that each species had been purposely created; and this led to my tacitly assuming that every detail of structure, excepting rudiments, was of some special, though unrecognized, service. Any one with this assumption in his mind would naturally extend the action of Natural Selection, either during past or present times, too far. Some of those who admit the principle of evolution, but reject Natural Selection, seem to forget, when criticising my work, that I had the above two objects in view; hence, if I have erred in giving to Natural Selection great power, which I am far from admitting, or in having exaggerated its power, which is in itself probable, I have at least, as I hope, done good service in aiding to overthrow the dogma of separate creations." In one other respect Mr. Darwin has modified his views of the action of Natural Selection, in consequence of a valuable criticism in the North British Review of June, 1&67 ; and Mr. Mivart regards this modification as very important, and says of it that "this admission seems almost to amount to a change of front in the face of the enemy." It is not, as we shall see, an important modification at all, and does not change in any essential particular the theory as propounded in the first edi- tion of the " Origin of Species," but Mr. Mivart's opinion of it has helped us to discover what, without this confirmation, seemed almost incredible, — how completely he has misappre- hended, not merely the use of the theory in special applica- tions, which is easily excusable, but also the nature of its gen- eral operation and of the causes employed by it; thus furnishing an additional illustration of what he says in his Introduction, that " few things are more remarkable than the way in which 1 4 o PHILOSOPHICAL DISCUSSIONS. it [this theory] has been misunderstood." One other consid- eration has also been of aid to us. In his concluding chapter on "Theology and Evolution," in which he very ably shows, and on the most venerable authority, that there is no necessary conflict between the strictest orthodoxy and the theory of evo- lution, he remarks (and quotes Dr. Newman) on the narrowing effect of single lines of study. Not only inabilities may be produced by a one-sided pursuit, but "a positive distaste may grow up, which, in the intellectual order, may amount to a spontaneous and unreasoning disbelief in that which appears to be in opposition to the more familiar concept, and this at all times." This is, of course, meant to apply to those who, from want of knowledge, lack interest in and even acquire a distaste for theological studies. But it also has other and equally important applications. Mr. Mivart, it would at first sight seem, being distinguished as a naturalist and also versed in theology, is not trammeled by any such narrowness as to disable him from giving just weight to both sides of the question he discusses. But what are the two sides ? Are they the view of the theologian and the naturalist ? Not at all. The debate is between the theologian and descriptive naturalist on one side, or the theologian and the student of natural history in its narrowest sense, that is, systematic biol- ogy; and on the other side the physical naturalist, physiolo- gist, or theoretical biologist. Natural history and biology, or the general science of life, are very comprehensive terms, and comprise in their scope widely different lines of pursuit and a wide range of abilities. In fact, the sciences of biology contain contrasts in the objects, abilities, and interests of scientific pursuit almost as wide as that presented by the physical sci- ences generally, and the sciences of direct observation, descrip- tion, and classification. The same contrast holds, indeed, even in a science so limited in its material objects as astronomy. The genius of the practical astronomer and observer is very different from that of the physical astronomer and mathema- tician; though success in this science generally requires now- adays that some degree of both should be combined. So the genius of the physiologist is different from that of the naturalist THE GENESIS OF SPECIES. T 4 I 4 proper, though in the study of comparative anatomy the ob- server has to exercise some of the skill in analysis and in the use of hypotheses in which the student of the physical sciences displays his genius in the search for unknown causes. We may, perhaps, comprise all the forms of intellectual genius (exclud- ing aesthetics) under three chief classes, namely, first, the genius that pursues successfully the researches for unknown causes by the skillful use of hypothesis and experiment; secondly, that which, avoiding the use of hypotheses or preconceptions alto- gether and the delusive influence of names, brings together in clear connections and contrasts in classification the objects of nature in their broadest and most real relations of resem- blance; and thirdly, that genius which seeks with success for reasons and authorities in support of cherished convictions. That Mr. Mivart may have the last two forms of genius, even in a notable degree, we readily admit; but that he has not the first to the degree needed for an inquiry, which is essentially a branch of physical science, we propose to show. We have already pointed out how his theological education, his school- ing against Democritus, has misled him in regard to the mean- ing of "accidents" or accidental causes in physical science; as if to the physical philosopher these could possibly be an absolute and distinct class, not included under the law of cau- sation, "that every event must have a cause or determinate antecedents," whether we can trace them out or not. The accidental causes of science are only "accidents" relatively to the intelligence of a man. Eclipses have the least of this character to the astronomer of all the phenomena of nature; yet to the savage they are the most terrible of monstrous acci- dents. The accidents of monstrous variation, or even of the small and limited variations normal in any race or species, are only accidents relatively to the intelligence of the naturalist, or to his knowledge of general physiology. An accident is what cannot be anticipated from what we know, or by any intelli- gence, perhaps, which is less than omniscient. But this is not the most serious misconception of the acci- dental causes of science, which Mr. Mivart has fallen into. He utterly mistakes the particular class of accidents concerned in 142 PHILOSOPHICAL DISCUSSIONS. the process of Natural Selection. To make this clear, we will enumerate the classes of causes which are involved in this proc- ess. In the first place, there are the external conditions of an animal's or plant's life, comprising chiefly its relations to other organic beings, but partly its relations to inorganic na- ture, and determining its needs and some of the means of satisfying them. These conditions are consequences of the external courses of events or of the partial histories of organic and inorganic nature. In the second place, there are the general principles of the fitness of means to ends, or of sup- plies to needs. These comprise the best ascertained and most fundamental of all the principles of science, such as the laws of mechanical, optical, and acoustical science, by which we know how a leg, arm, or wing, a bony frame, a muscular or a vascular system, an eye or an ear, can be of use. In the third place, there are the causes introduced by Mr. Darwin to the attention of physiologists, as normal facts of organic nature, the little known phenomena of variation, and their relations to the laws of inheritance. There are several classes of these. The most important in the theory of Natural Selection are the diversities always existing in any race of animals or plants, called "individual differences," which always determine a bet- ter fitness of some individuals to the general conditions of the existence of a race than other less fortunate individuals possess. The more than specific agreements in characters, which the best fitted individuals of a race must thus exhibit, ought, if possible, according to Cuvier's principles of zoology, to be included in the description of a species (as a norm or type which only the best exhibit), instead of the rough averages to which the naturalist really resorts in defining species by marks or characters that are variable. But probably such averages in variable characters are really close approximations to the characters of the best general adaptation ; for variation being, so far as known, irrespective of adaptation, is as likely to exist to the same extent on one side of the norm of utility as on the other, or by excess as generally as by defect. Though varia- tion is irrespective of utility, its limits are not. Too great a departure from the norm of utility must put an end to life anil THE GENESIS OF SPECIES. 143 its successions. Utility therefore, in conjunction with the laws of inheritance, determines not only the middle line or safest way of a race, but also the bounding limits of its path of life ; and so long as the conditions and principles of utility embodied in a form of life remain unchanged, they will, together with the laws of inheritance, maintain a race unchanged in its average characters. "Specific stability," therefore, for which theological and descriptive naturalists have speculated a transcendental cause, is even more readily and directly accounted for by the causes which the theory of Natural Selection regards than is specific change. But just as obviously it follows from these causes that a change in the conditions and resources of utility, not only may but must change the normal characters of a species, or else the race must perish. Again, a slow and grad- ual change in the conditions of existence must, on these principles, slowly change the middle line or safest way of life (the descriptive or graphic line) ; but always, of course, this change must be within the existing limits of variation, or the range of "individual differences." A change in these limits would then follow, or the range of "individual differences" would be extended, at least, so far as we know, in the direc- tion of the change. That it is widened or extended to a greater range by rapid and important changes in conditions of exist- ence, is a matter of observation in many races of animals and plants that have been long subject to domestication or to the capricious conditions imposed by human choice and care. This phenomenon is like what would happen if a roadway or path across a field were to become muddy or otherwise obstructed. The traveled way would swerve to one side, or be broadened, or abandoned, according to the nature and degree of the ob- struction, and to the resources of travel that remained. This class of variations, that is, " individual differences," constant and normal in a race, but having different ranges in different races, or in the same race under different circumstances, may be regarded as in no proper sense accidentally related to the advantages that come from them ; or in no other sense than a tendril, or a tentacle, or a hand searching in the dark, is acci- 1 4 4 PHILOSOPHICAL DISCUSSIONS. dentally related to the object it succeeds in finding. And yet we say properly that it was by "accident" that a certain ten- dril was put forth so as to fulfill its function, and clasp the par- ticular object by which it supports the vine; or that it was an accidental movement of the tentacle or hand that brought the object it has secured within its grasp. The search was, and continues to be, normal and general ; it is the particular suc- cess only that is accidental ; and this only in the sense that lines of causation, stretching backwards infinitely, and unre- ^ lated except in a first cause, or in the total order of nature, come together and by their concurrence produce it. Yet over even this concurrence " law " still presides, to the effect that for every such concurrence the same consequences follow. But Mr. Mivart, with his mind filled with horror of "blind chance," and of " the fortuitous concourse of atoms," has en- tirely overlooked the class of accidental variations, on which, even in the earlier editions of the " Origin of Species," the theory of Natural Selection is based, and has fixed his attention exclu- sively on another class, namely, abnormal or unusual variations, which Mr. Darwin at first supposed might also be of service in this process. The error of his critic might, perhaps, be re- garded as due to Mr. Darwin's failure to distinguish suffi- ciently the two classes, as well as to his overlooking, until it was pointed out in the article in the "North British Review," before referred to, the fact that the latter class could be of no service; if it were not that Mr. Mivart's work is a review of the last edition of the " Origin of Species " and of the treatise on "Animals and Plants under Domesti- cation," in both of which Mr. Darwin has emphatically dis- tinguished the two classes, and admitted that it is upon the first class only that Natural Selection can normally depend ; though the second class of unusual and monstrous variations may give rise, by highly improbable though possible accidents, to changes in the characters of whole races. Mr. Mivart char- acterizes this admission by the words we have quoted, that "it seems almost to amount to a change of front in the face of the enemy"; of which it might have been enough to say, that the strategy of science is not the same as that of rhetorical dispu- THE GENESIS OF SPECIES. 145 tation, and aims at cornering facts, not antagonists But Mr. Mivart profits by it as a scholastic triumph over he :esy, which he insists upon celebrating, rather than as a correction of his own misconceptions of the theory. He continues throughout his book to speak of the variations on which Natural Selection depends as if they were all of rare occurrence, like abrupt and monstrous variations, instead of being always present in a race ; and also as having the additional disadvantage of being "in- dividually slight," "minute," "insensible," "infinitesimal," "fortuitous," and "indefinite." These epithets are variously combined in different passages, but his favorite compendious formula is, "minute, fortuitous, and indefinite variations." When, however, he comes to consider the enormous time which such a process must have taken to produce the present forms of life, he brings to bear all his forces, and says (p. 154) : "It is not easy to believe that less than two thousand million years would be required for the totality of animal development by no other means than minute, fortuitous, occasional, and in- termitting variations in all conceivable directions." This ex- ceeds very much — by some two hundred-fold — the length of time Sir William Thomson allows for the continuance of life on the earth. It is difficult to see how, with such uncertain "fortuitous, occasional, and intermitting" elements, our author could have succeeded in making any calculations at all. On the probability of the correctness of Sir William Thomson's physical arguments "the author of this book cannot presume to advance an opinion; but," he adds (p. 150), "the fact that they have not been refuted pleads strongly in their favor when we consider how much they tell against the theory of Mr. Darwin." He can, it appears, judge of them on his own side. For the descriptive epithets which Mr. Mivart applies to the variations on which he supposes Natural Selection to depend he has the following authority. He says (p. 35) : " N dw it is distinctly enunciated by Mr. Darwin that the spontaneous vari- ations upon which his theory depends are individually slight, minute, and insensible. He says (Animals and Plants imder Domestication, Vol. II, p. 192): 'Slight individual differences, however, suffice for the work, and are probably the sole difler- 7 146 PHILOSOPHICAL DISCUSSIONS. ences which are effective in the production of new species.' " After what we have said as to the real nature of the differences from which nature selects, it might be, perhaps, unnecessary to explain what ought at least to have been known to a natu- ralist, that by "individual differences" is meant the differences between the individuals of a race of animals or plants ; that the slightness of them is only relative to the differences between the characters of species, and that they may be very consider- able in themselves, or their effects, or even to the eye of the naturalist. How the expression "slight individual differences" could have got translated in the writer's mind into "individu- ally slight, minute, and insensible" ones, has no natural expla- nation. But this is not the only instance of such an unfathom- able translation in Mr. Mivart's treatment of the theory of Natural Selection. Two others occur on page 133. In the first he says : " Mr. Darwin abundantly demonstrates the vari- ability of dogs, horses, fowls, and pigeons, but he none the less shows the very small extent to which the goose, the peacock, and the guinea-fowl have varied. Mr. Darwin attempts to explain this fact as regards the goose by the animal being valued only for food and feathers, and from no pleasure having been felt in it on other accounts. He adds, however, at the erid, the striking remark, which concedes the whole position, ' but the goose seems to have a singularly inflexible organiza- tion.' 1 " The translation is begun in the author's italics, and completed a few pages further on (p. 141), where, recurring to this subject, he says : "We have seen that Mr. Darwin him- self implicitly admits the principle of specific stability in assert- ing the singular inflexibility of the organization of the goose." This is what is called in scholastic logic, Fallacia a dicto secundum quid ad dictum simpliciter. The obvious meaning, both from the contexts and the evidence, of the expression, "singularly inflexible," is that the goose has been much less changed by domestication than other domestic birds. But this relative inflexibility is understood by Mr. Mivart as an admission of an absolute one, in spite of the evidence that geese have va- ried from the wild type, and have individual differences, and even differences of breeds, which are sufficiently conspicuous, THE GENESIS OF SPECIES. 147 even tc the eye of a goose. The next instance of Mr. Mivart's translations (p. 133) is still more remarkable. He continues: " This is not the only place in which such expressions are used. He [Mr. Darwin] elsewhere makes use of phrases which quite harmonize with the conception of a normal specific con- stancy, but varying greatly and suddenly at intervals. Thus he speaks of a whole organism seeming to have become plastic and tending to depart from the parental type (' Origin of Spe- cies,' 5th edit., 1869, p. 13)." The italics are Mr. Mivart's. The passage from which these words are quoted (though they are not put in quotation-marks) is this : " It is well worth while carefully to study the several treatises on some of our old cul- tivated plants, as on the hyacinth, potato, even the dahlia, etc. ; and it is really surprising to note the endless points in structure and constitution in w T hich the varieties and sub-varieties differ slightly from each other. The whole organization seems to have become plastic, and tends to depart in a slight degree from that of the parental type." The words that we have italicized in this quotation are omitted by Mr. Mivart, though essential to the point on which he cites Mr. Darwin's authority, namely, as to the organism "varying greatly and suddenly at intervals." Logic has no adequate name for this fallacy ; but there is an- other in Mr. Mivart's understanding of the passage which is very familiar, — the fallacy of ambiguous terms. Mr. Darwin obviously uses the word " plastic " in its secondary signification as the name of that which is "capable of being moulded, mod- eled, or fashioned to the purpose, as clay." His critic quite as obviously understands it in its primary signification as the name of anything "having the power to give form." But this is a natural enough misunderstanding, since in scholastic philosophy the primary signification of "plastic" is the prevail- ing one. Such being Mr. Mivart's misconceptions of the principle of Natural Selection, and such their source, it would be useless to follow him in his tests of it by hypothetical illustrations from the history of animals; but we are bound to make good our assertion that his difficulties have arisen, not only from his want of a clear mental grasp of principles, but also from 1 4 8 PHIL OSOPHICA L DISC US S IONS. an inadequate knowledge of the resources of legitimate hy- pothesis to supply the unknown incidental causes through which the principle has acted. These deficiencies of knowledge and imagination, though more excusable, are not less conspic- uous in his criticisms than the defects we have noticed. He says (p. 59): "It may be objected, perhaps, that these diffi- culties are difficulties of ignorance ; that we cannot explain them, because we do not know enough of the animals." It is not surprising that he adds: "But it is here contended that this is not the case; it is not that we merely fail to see how Natural Selection acted, but that there is a positive incompatibility between the cause assigned and the results." And no wonder that he remarks at the close of the chapter (Chapter II): "That minute, fortuitous, and indefinite varia- tions could have brought about such special forms and mod- ifications as have been enumerated in this chapter seems to contradict, not imagination, but reason." In this chapter on " Incipient Structures," two facts are quite overlooked, — the one, which is so conspicuous in the principles of comparative anatomy, how few the fundamental structures are, which have been turned to such numerous uses; that is, how meagre have been the resources of Natural Selection, so far as it has depended on the occurrence of structures which were of no previous use, or were not already partially useful in directions in which they have been modified by the selection and inheritance of "individual differences"; the other, how important to Natural Selection have been the principles of indirect utility and "correlated acquisi- tion," dependent as they are on ultimate physical laws. The human hand is still useful in swimming, and the fishes' fins could even be used for holding or clasping, if there were occasion for it. We might well attribute the paucity of indif- ferent types of structure to the agency of the rarest accidents of nature, though not in a theological sense. Animals and plants are no longer dependent for improvement on their occurrence, and, perhaps, never were after their competition and struggle for existence had fully begun. It is so much easier for them to turn to better account powers that they already THE GENESIS OF SPECIES. 149 possess in small degrees. Previously to such a competition and struggle, when the whole field of the inorganic condi- tions of life was open to simple organisms, they were doubtless much more variable than afterwards. But variability would then have been, as it is now, in no absolute sense accidental. On the contrary, variation, instead of comparative stability in species, would have been the most prominent normal feature of life. The tentative powers of life, trying all things, but not holding fast to that which is good, or not so firmly as after- wards, instead of its hereditary features, would have been its most characteristic manifestation. Our author's general diffi- culty in this chapter is as to how variations too small to have been of use could have been preserved, and he is correct in thinking that it could not be by Natural Selection, or the sur- vival of the fittest, but wrong in thinking that variations are generally so rare or so insignificant, even in present forms of life as to require a power other than those of life in general to bring them forth when needed, or to produce them in useful amounts. The first example of the working of Natural Selection is the well-known case of the neck of the giraffe. This, it has been imagined, though not by Mr. Darwin, was produced by its supposed use in aiding this animal to feed on the foliage of trees, and by the occasional advantage of length of neck to the highest reaching individuals, when in drought and scarcity the ground vegetation and lower foliage were consumed enabling them to survive the others and in continuing the species, to transmit this advantage to their offspring. With- out denying that this is an excellent hypothetical illustra- tion of the process of Natural Selection, Mr. Mivart attacks its probability as a matter of fact. In reply to it he says : " But against this it may be said, in the first place, that the argument proves too much; for, on this supposition, many species must have tended to undergo a similar modification and we ought to have at least several forms similar to the giraffe developed from different Ungulata" or hoofed beasts. We would even go further than Mr. Mivart, and hold that, on the hypothesis in question, not only several forms, but i5° PHIL OSOPHICA L DISC US S IONS. the whole order of Ungulata, or large portions of it, should have been similarly modified; at least those inhabiting re- gions subject to droughts and presenting the alternative of grazing on the ground and browsing on the foliage of high trees. But as these alternatives do not universally exist in regions inhabited by such animals, very long necks would not, perhaps, if this hypothesis were true, characterize the whole order; as the habit of herding does, for example. We may ob- serve, however, that this illustration from the giraffe's neck is not an argument at all, and proves nothing, though the hy- pothesis employed by it is very well called in question by Mr. Mivart's criticism. But can Mr. Mivart suppose that, having fairly called in question the importance of the high-feeding use of the giraffe's neck, he has thereby destroyed the utility of the neck altogether, not only to the theory of Natural Selection, but also to the animal itself? Is there, then, no important use in the giraffe's neck? Is it really the monstrosity it appears to be, when seen out of relation to the normal conditions of the animal's life ? But if there be any utility left in the neck, as a teleologist or a believer in Final Causes would assume without question, and in spite of this criticism, then this other utility might serve the purposes of Natural Selection even better perhaps than that of the mistaken hypothesis. If Mr. Mi- vart had approached this subject in the proper spirit, his criticism would probably have led him to an important ob- servation, which his desire to discredit a much more im- portant discovery has hidden from his view. He would have inquired what are the conditions of existence of the Ungulates generally and of the giraffe in particular, which are so close pressing and so emphatically attest the grounds of their severest struggle for life, as to be likely to cause in them the highest degree of specialty and adaptation. The question of food is obviously not concerned in such a struggle, for this order of animals lives generally upon food which is the most abundant and most easily obtained. Mr. Mivart compares his objection to one that has been made against Mr. Wallace's views as to the uses of color in animals, that "color being dangerous, should not exist in nature,' or THE GENESIS OF SPECIES. ISI that " a dull color being needful, all animals should be so col- ored." He quotes Mr. Wallace's reply, but does not take the clue to the solution of his difficulty respecting the giraffe's neck, which it almost forces on him. This reply was, that many an- imals can afford brilliant colors, and their various direct uses or values, when the animals are otherwise provided with suffi- cient protection, and that brilliant colors are even sometimes indirectly protective. The quills of the porcupine, the shells of tortoises and mussels, the very hard coats of certain beetles, the stings of certain other insects, the nauseous taste of brilliantly colored caterpillars, and other instances, are given as examples of protection with color. Now, what bearing has this on the long neck of the giraffe? According to Mr. Mivart, who is himself at this point on the defensive, it is as follows. He says: "But because many different kinds of animals can elude the observation or defy the attack of enemies in a great variety of ways, it by no means follows that there are any similar number and variety of ways for attaining vegetable food in a country where all such food other than the lofty branches of trees has been destroyed. In such a country we have a number of vegetable-feeding Ungulates, all of which present minute variations as to the length of the neck." Mr. Mivart is appar- ently not aware that he is here arguing, not against the theory of Natural Selection, but against a subordinate and false hy- pothesis under it. But if he thinks thus to undermine the theory, it must be because he is not aware of, or has not present to his imagination, the numberless ingenuities of nat- ure, and the resources of support the theory has to rest upon. There can be no doubt that the neck of the giraffe, whatever other uses it can be put to, and it is put to several, is pre-emi- nently useful as a watch-tower. Its eyes, large and lustrous, "which beam with a peculiarly mild but fearless expression, are so placed as to take in a wider range of the horizon than is subject to the vision of any other quadruped. While browsing on its favorite acacia, the giraffe, by means of its laterally pro- jecting orbits, can direct its sight so as to anticipate a threat- ened attack in the rear from the stealthy lion or any other foe of the desert." When attacked, the giraffe can defend itself I 5 2 PHILOSOPHICAL DLSCUSSLONS. by powerful blows with its well-armed hoofs, and even its short horns can inflict fatal blows by the sidelong swing of its neck. But these are not its only protections against danger. Its nos- trils can be voluntarily closed, like the camel's, against the sandy, suffocating clouds of the desert. "The tail of the giraffe looks like an artificially constructed fly-flapper; and it seems at first incredible," says Mr. Darwin, "that this could have been adapted for its present purpose by successive slight modi- fications, each better and better fitted, for so trifling an object as to drive away flies ; yet we should pause before being too positive, even in this case, for we know that the distribution and existence of cattle and other animals in South America absolutely depend on their power of resisting the attacks of insects; so that individuals which could, by any means, defend themselves from these small enemies, would be able to range into new pastures, and thus gain a great advantage. It is not that the larger quadrupeds are actually destroyed (except in rare cases) by flies, but they are incessantly harrassed and their strength reduced, so that they are more subject to disease, or not so well enabled in a coming dearth to search for food, or to escape from beasts of prey." This passage recalls our main problem, which does not con- cern the giraffe alone, but all the Ungulates; and its solution will show that this order of animals exhibits, almost as well as Mr. Wallace's examples, the resources that nature has for the protection of animals that have the disadvantage, not, indeed, generally of brilliant colors, but of exposure by living exclu- sively on bulky and comparatively innutritious food. Nearly all the resources of defensive warfare are exhausted in their specialties of protection. The giraffe alone is provided with a natural watch-tower, but the others are not left without defense. All, or nearly all, live in armies or herds, and some post senti- nels around their herds. The numerous species of the ante- lope resort to natural fortifications or fastnesses. "They are the natives for the most part of the wildest and least accessible places in the warmer latitudes of the globe, frequenting the cliffs and ledges of mountain rocks or the verdure-clad banks of tropical streams, or the oases of the desert." Other tribes THE G EXE SIS OF SPECIES, I53 depend on their fleetness, and on hiding in woods like the deer. Others, again, on great powers of endurance in flight and long marches, like the camels with their commissaries of provision. Others, again, with powerful frames, like the rhinoceros and the bisons, resort to defensive attack. The ruminant habits and organs of large numbers are adapted to rapid and danger- ous foraging, and to digestion under protection from beasts of prey and insects. But Mr. Mivart, with little fertility of defense for the theory of Natural Selection, is still not without some ingenuity in at- tack. He objects, in the second place, that the longest necked giraffes, being by so much the larger animals, would not be strong in proportion, but would need more food to sustain them, a disadvantage which would, perhaps, more than out- balance the neck in times of drought ; and he cites Mr. Spen- cer's ingenious speculations on the relations of size, food, and strength, in confirmation of this objection. But he forgets or overlooks the important physiological law of the compensa- tion or economy of growth which prevails in variations. A longer neck does not necessarily entail a greater bulk or weight on the animal as a whole. The neck may have grown at the expense of the hind parts in the ancestors of the giraffe. If we met with an individual man with a longer neck than usual, we should not expect to find him heavier, or relatively weaker, or requiring more food on that account. But let us pass to the next illustration of the insufficiency of Natural Selection. This is the difficulty Mr. Mivart finds in attributing to this cause various cases of mimicry or pro- tective resemblances of animals to other animals, or to other natural objects. In some insects this is carried to a won- derful extent. Thus, some which imitate leaves when at rest, in the sizes, shapes, colors, and markings of their wings, "extend the imitation even to the very injuries on those leaves made by the attacks of insects or fungi." Thus Mr. Wallace says of the walking-stick insects : " One of these creatures, obtained by myself in Borneo, was covered over with foliaceous excrescences of a clear olive-green color so as exactly to resemble a stick grown over by creeping J 54 PHILOSOPHICAL DISCUSSIONS. moss or junger'mannia. The Dyak who brought it me assured me it was grown over with moss, although alive, and it was only after a most minute examination that I could convince myself it was not so." And in speaking of the leaf-butterfly, he says: "We come to a still more extraordinary part of the imitation, for we find representations of leaves in every stage of decay, variously blotched and mildewed, and pierced with holes, and in many cases irregularly covered with powdery black dots, gathered into patches and spots, so closely resem- bling the various kinds of minute fungi that grow on dead leaves that it is impossible to avoid thinking, at first sight, that the butterflies themselves have been attacked by real fungi." Upon these passages Mr. Mivart remarks : " Here imitation has attained a development which seems utterly beyond the power of the mere ' survival of the fittest ' to produce. How this double mimicry can importantly aid in the struggle for life seems puzzling indeed, but much more so how the first begin- nings of the imitation of such injuries in the leaf can be devel- oped in the animal into such a complete representation of them ; a fortiori, how simultaneous and similar first beginnings of imitations of such injuries could ever have been developed in several individuals, out of utterly indifferent and indetermi- nate infinitesimal variations in all conceivable directions." What ought to have been first suggested to a naturalist by this wonderful mimicry is, what clever entomologists some insectivorous birds must have become to be able to press the conditions of existence and the struggle for life in these in- sects to such a degree of specialty. But this, after all, is not so very wonderful, when we consider what microscopic sight these birds must have acquired and what practice and exclusive interest in the pursuit ! We may feel pretty confident, how- ever, that neither Natural Selection nor any occult or transcend- ental cause has ever carried protective mimicry beyond eye- sight, though it may well be a better eyesight than that even of a skillful naturalist. There is no necessity to suppose, with our author, that the variations on which this selection depended were either simultaneous, or infinitesimal, or indifferent, for "individual differences" are always considerable and generally THE GENESIS OF SPECIES. ^S. greatest in directions in which variations have already most recently occurred, as in characters in which closely allied races, differ most from each other; but, doubtless, a very long time was required for these very remarkable cases of mimicry to come to pass. The difficulties they present resemble those of the development of sight itself, on which Mr. Mivart com- ments elsewhere ; but in these particular cases the conditions of "hide and seek" in the sport of nature offer correlated difficulties, which, like acid and alkali, serve to neutralize each other. In these cases, four distinct forms of life of widely diverse origins, or very remotely connected near the beginnings of life itself, like four main branches of a tree, have come to- gether into closest relations, as parts of the foliage of the four main branches might do. These are certain insectivorous birds, certain higher vegetable forms, the imitated sticks or leaves, certain vegetable parasites on them, and the mimicking insects. But the main phenomenon was and is the neck-and- neck race of variation and the selection between the powers of hiding in the insect and the powers of finding in the bird. Mr. Mivart overlooks the fact that variations in the bird are quite as essential to the process as those of the insect, and has chosen to consider elsewhere the difficulties which the developments of the eye present, and to consider them in equal independence of its obvious uses. The fact that these, as well as other ex- traordinary cases of mimicry, are found only in tropical cli- mates, or climates equable not only in respect to short periodic but also secular changes, accords well with the probable Length of time in which this competition has been kept up ; and the extraordinary, that is, rare character of the phenomenon agrees well with the probable supposition that it has always begun in what we call in science "an accident." If its beginnings were common, their natural consequences would also be common, and would not be wonderful ; and if it arose from a destructive, unintelligent, evil principle, — from Ahriman, — it has, at least, shown how the course of nature has been able to avoid destruc- tion, to the astonishment of human intelligence, and how Oromasdes has been able to defeat his antagonist by turning evil into good. I5 6 PHILOSOPHICAL DISCUSSIONS. Let us take next Mr. Mivart's treatment of a supposed origin of the mammary, or milk glands : "Is it conceivable," he asks (p. 60), "that the young of any animal was ever saved from destruction by accidentally sucking a drop of scarcely nutritious fluid from an accidentally hypertrophied cutaneous gland of its mother ? And even if one was so, what chance was there of the perpet- uation of such a variation? On the hypothesis of 'Natural Selection' itself we must assume that, up to that time, the race had been well adapt- ed to the surrounding conditions; the temporary and accidental trial and change of conditions, which caused the so-sucking young one to be the 'fittest to survive' under the supposed circumstances, would soon cease to act, and then the progeny of the mother, with the accidentally hyper- trophied sebaceous glands, would have no tendency to survive the far- outnumbering descendants of the normal ancestral form." Here, as before, Mr. Mivart stakes the fate of the theory on the correctness of his own conceptions of the conditions of its action. He forgets, first of all, that the use of a milk gland in its least specialized form requires at least a sucking mouth, and that sucking mouths and probosces have very extensive uses in the animal kingdom. They are good for drinking water and nectar, and are used for drawing blood as well as milk ; and, without reference to alimentation, are, still serviceable for sup- port to parasitical animals. Might not the young, which before birth are, in a high degree, parasitical in all animals, find it highly advantageous to continue the habit after birth, even without reference to food, but for the generally quite as impor- tant use of protection against enemies, by clinging by a suck- ing mouth to the body of its dam ? If this should cause seba- ceous glands to become hypertrophied and ultimately a valuable or even an exclusive source of nutrition, it would, perhaps, be proper to describe the phenomenon as an unintended or acci- dental, but not as a rare or improbable one. Moreover, though on the theory of Natural Selection (or, indeed, on any theory of the continuance of a race by modifications of structures and habits), the race must, while it lives, be fitted to live, yet it need be no more fitted to do so than to survive in its offspring. No race is so well fitted to its general conditions of existence, but that some individuals are better fitted than others, and have, on the average, an advantage. And new resources do not imply abandonment of the old, but only additions to them, THE GENESIS OF SPECIES. 157 giving superiorities that are almost never superfluous. How, indeed, but by accidents of the rarest occurrence, could varia- tion (much less selection) give superfluous advantages, on the whole, or except temporarily and so far as normal variations anticipate in general, regular, or usual changes in the condi- tions of existence ? We have, to be sure, on the hypothesis we have proposed, still to account for the original of the sucking mouth, though its numerous uses are obvious enough, on the really uniform and unvarying types of natural law, the laws of inorganic physics, the principles of suction. But we are not ambitious to rival nature in ingenuity, only to contrast its re- sources with those of our naturalist. His next example is a criticism of the theory of Sexual Selection. Speaking . of apes, he says: "When we consider what is known of the emotional nature of these animals and the periodicity of its intensification, it is hardly credible that a female would often risk life or limb through her ad- miration of a trifling shade of color or an innnitesimally greater, though irresistibly fascinating degree of wartiness." Is it credible that Mr. Mivart can suppose that the higher or spiritual emotions, like affection, taste, conscience, ever act directly to modify or compete with the more energetic lower impulses, and not rather by forestalling and indirectly regulating them, as by avoiding temptation in the case of con- science; or by establishing social arrangements, companion- ships, friendships, and more or less permanent marriages in the case of sexual preferences ? All such arrangements, all grounds for the action of taste or admiration, or any but the most monstrous friendships, are prevented or removed in the lives of caged beasts. His example and his inference from it are as much as if an explorer should discover a half-famished tribe of savages sustaining life upon bitter and nauseous food, and should conclude that not only these but all savages, the most provident, or even all men, are without any choice in food, and that in providing for future wants they are influ- enced by no other considerations than the grossest cravings of appetite. But to return to Natural Selection. The next example is i58 PHILOSOPHICAL DISCUSSIONS. that of the rattling and expanding powers of poisonous snakes. The author says that "in poisonous serpents, also, we have structures which, at all events, at first sight, seem positively hurtful to these reptiles. Such are the rattle of the rattlesnake and the expanding neck of the cobra, the former serving to warn the ear of the intended victim as the latter warns the eye." This "first sight" is all the use our author discovers in these organs; but why should these warnings be intended or used to drive away intended victims rather than enemies? Or is it among the intentions of nature to defeat those of the ser- pent? If the effects of such "warnings" really were to deprive these snakes of their proper food, would not experience itself and intelligence be sufficient in the wily serpent to correct such perverse instincts? It is, indeed, at first sight, curious that certain snakes, though these are the sluggish kinds, and cannot so easily escape their enemies by flight as others can, should be provided, not only with poisonous fangs, but with these means of warning either victims or dangerous enemies. But Mr. Wallace has furnished a clew to their correlation by his example of the relations between conspicuous colors and nauseous tastes in many caterpillars, the color serving as a sign of the taste and warning birds not to touch these kinds. The poisonous fang and its use are expensive and risky means of defense; the warnings associated with them are cheap and safe. But if, as is very likely, these "warnings" are also used against intended victims, they can only be used either to paralyze them with terror or allure them from curiosity, or to produce in them that curious and paralyzing mixture of the two emotions, alarm and something like curiosity, which is all that is probably true of the supposed powers of fascination * in ser- pents. Perhaps, also, the rattle serves to inspire the sluggish snake itself with courage; and in this case the rattle will serve * This is a real condition of mind in the subject of it; a condition in which interest or emotion gives to an idea such fixity and power that it takes possession at a fatal mo- ment of the will and acts itself out; as in the fascination of the precipice. It is not, however, to be regarded as a natural contrivance in the mental acquisitions of the vic- tims for the benefit of the serpent any more than the serpent's warnings are for their benefit ; but as a consequence of ultimate mental laws in general, of which the serpent s faculties and habits take advantage. THE GENESIS OF SPECIES. 159 all the purposes that drums, trumpets, and gongs do in human warfare. The swaying body and vibrating tongue of most snakes, and the expanding neck and the hood of the cobras, may serve for banners. But the rattle has also been supposed to serve as a sexual call, very much as the inspirations of war- fare are turned into the allurements of the tournament, or as gongs also serve to call travelers to dinner. What poverty of resources in regard to the relations of use in the lives of ani- mals thus distinguishes our naturalist from the natural order of things ! What wealth and capital are left for the employ- ments and industries of Natural Selection ! In the next chapter Mr. Mivart charges the theory of Natural Selection with inability to account for independent similarities of structure; "that it does not harmonize with the co-existence of closely similar structures of diverse origin," like the dental structures in the dog and in the carnivorous marsupial, the Thylacine, closely similar structures and of exactly the same utilities, though belonging to races so diverse that their com- mon ancestors could not have been like them in respect to this resemblance. But these structures really differ in points not essential to their utilities; in characters which, though incon- spicuous, are marks of the two great divisions of mammalia, to which these animals belong. Mr. Mivart here attacks the theory in its very citadel, and has incautiously left a hostile force in his rear. He has claimed in the preceding chapter for Natural Selection that it ought to have produced several independent races of long-necked Ungulates, as well as the giraffe; so that, instead of pursuing his illustrations any further, we may properly demand his surrender. Of course Natural Selection requires for similar products similar means and con- ditions; but these are of such a general sort that they belong to wide ranges of life; and as it does not act by "blind chance," or theological accidents, but by the invariable laws of nature and the tentative powers of life, it is not surprising that it often repeats its patterns independently of descent, or of the copying powers of inheritance. That the highest products of nature are not the results of the mere forces of inheritance, and do not come from the birth j6o philosophical discussions. of latent powers and structures, seems to be the lesson of the obscure discourse in which Jesus endeavored to instruct Nico- demus the Pharisee. How is it that a man can be born again, acquire powers and characters that are not developments of what is already innate in him ? How is it possible when he is old to acquire new innate principles, or to enter a second time into his mother's womb and be born ? The reply does not suggest our author's hypothesis of a life turning over upon a new " facet," or a new set of latent inherited powers. Only the symbols, water and the Spirit, which Christians have ever since worshiped, are given in reply; but the remarkable illus- tration of the accidentality of nature is added, which has been almost equally though independently admired. " Marvel not that I said unto thee, Ye must be born again. The wind blow- eth where it listeth, and thou hearest the sound thereof, but canst not tell whence it cometh and whither it goeth; so is every one that is born of the Spirit." The highest products of nature are the outcome of its total and apparently accidental orders; or are born of water and the Spirit, which symbolize creative power. To this the Pharisee replied: "How can these things be?" And the answer is still more significant: "Art thou a master of Israel and knowest not these things ?" We bring natural evidences, "and ye receive not our witness. If I have told you earthly (natural) things, and ye believe not, how shall ye believe if I tell you heavenly (supernatural) things ? " The bearing of our subject upon the doctrine of Final Causes in natural history has been much discussed and is of considerable importance to our author's theory and criticism. But we propose, not only to distinguish between this branch of theology and the theories of inductive science on one hand, but still more emphatically, on the other hand, between it and the Christian faith in divine superintendency, which is very lia- ble to be confounded with it. The Christian faith is that even the fall of a sparrow is included in this agency, and that as men are of more value than many sparrows, so much more is their security. So far from weakening this faith by showing the connection between value and security, science and the theory of Natural Selection have confirmed it. The very agencies THE GENESIS OF SPECIES. 161 that give values to life secure them by planting them most broadly in the immutable grounds of utility. But Natural Theology has sought by Platonic, not Christian, imaginations to discover, not the relations of security to value, but some- thing worthy to be the source of the value considered as abso- lute, some particular worthy source of each valued end. This is the motive of that speculation of Final Causes which Bacon condemned as sterile and corrupting to philosophy, interfering, as it does, with the study of the facts of nature, or of what is, by preconceptions, necessarily imperfect as to what ought to be; and by deductions from assumed ends, thought worthy to be the purposes of nature. The naturalists who " take care not to ascribe to God any intention," sin rather against the spirit of Platonism than that of Christianity, while obeying the pre- cepts of experimental philosophy. Though, as our author says, in speaking of the moral sense and the impossibility, as he thinks, that the accumulations of small repugnances could give rise to the strength of its abhorrence and reprobation; though, as he says, " no stream can rise higher than its source"; while fully admitting the truth of this, we would still ask, Where is its source? Surely not in the little fountains that Platonic explorers go in search of, a priori, which would soon run dry but for the rains of heaven, the water and the vapor of the distilling atmosphere. Out of this come also the almost weightless snow-flakes, which, combined in masses of great gravity, fall in the avalanche. The results of moralizing Pla- tonism should not be confounded with the simple Christian faith in Divine superintendence. The often-quoted belief of Professor Gray, "that variation has been led along certain beneficial lines, like a stream along definite lines of irrigation," might be interpreted to agree with either view. The lines on which variations are generally useful are lines of search, and their particular successes, dependent, it is true, on no theo- logical or absolute accidents, may be regarded as being lines of beneficial variations, seeing that they have resulted through laws of nature and principles of utility in higher living forms, or even in continuing definite forms of life on the earth. But thousands of movements of variation, or efforts of search, have !62 PHILOSOPHICAL DISCUSSIONS. not succeeded to one that has. These are not continued along evil lines, since thousands of forms have perished in conse- quence of them for every one that has survived. The growth of a tree is a good illustration of this process, and more closely resembles the action of selection in nature generally than might at first sight appear ; for its branches are selected growths, a few out of many thousands that have begun in buds ; and this rigorous Selection has been effected by the accidents that have determined in surviving growths superior relations to their supplies of nutriment in the trunk and in ex- posure to light and air. This exposure (as great as is consist- ent with secure connection with the sources of sap) seems actually to be sought, and the form of the tree to be the result of some foresight in it. But the real seeking process is bud- ding, and the geometrical regularity of the production of buds in twigs has little or nothing to do with the ultimate selected results, the distributions of the branches, which are different for each individual tree. Even if the determinate variations really existed, — the "facets" of stable equilibrium in life, which Mr. Mivart supposes, — and were arranged with geometrical regu- larity on their spheroid of potential forms, as leaves and buds are in the twig, they would probably have as little to do with determining the ultimate diversities of life under the action of the selection which our author admits, as phyllotaxy has to do with the branching of trees. But phyllotaxy, also, has its utility. Its orders are the best for packing the incipient leaves in the bud, and the best for the exposure to light and air of the developed leaves of the stem. But here its utility ends, except so far as its arrangements also present the great- est diversity of finite elements, within the smallest limits, for the subsequent choice of successful growths ; being the nearest approaches that finite regularity could make io "indefinite vari- ations in all conceivable directions." The general resemblance of trees of a given kind depends on no formative principle other than physical and physiological properties in the woody tissue, and is related chiefly to the tenacity, flexibility, and vascularity of this tissue, the degrees of which might almost be inferred from the general form of the tree. It cannot be doubted, in THE GENESIS OF SPECIES. 163 the case pf the tree, that this tentative though regular budding has been of service to the production of the tree's growth, and that the particular growths which have survived and become the bases of future growths were determined by a beneficial though accidental order of events under the total orders of the powers concerned in the tree's development. But if a rigorous selection had not continued in this growth, no proper branching would have resulted. The tree would have grown like a cab- bage. Hence it is to selection, and not to variation, — or rather to the causes of selection, and not to those of variation, — that species, or well-marked and widely separated forms of life, are due. If we could study the past and present forms of life, not only in different continents, which we may compare to different individual trees of the same kind, or better, perhaps, to different main branches from the same trunk and roots, but could also study the past and present forms of life in different planets, then diversities in the general outlines would probably be seen sim- ilar to those which distinguish different kinds of trees, as the oak, the elm, and the pine ; dependent, as in these trees, on differences in the physical and physiological properties of living matters in the different planets, — supposing the planets, of course, to be capable of sustaining life, like the earth, or, at least, to have been so at some period in the history of the solar system. We might find that these general outlines of life in other planets resemble elms or oaks, and are not pyramidal in form like the pine, with a "crowning" anima^like man to lead their growths. For man, for aught we know or could guess, but for the highly probable accidents of nature, which blight the topmost terminal bud and give ascendency to some lateral one, except for these accidents, man may have always been the crown of earthly creation, or always "man," if you choose so to name and define the creature who, though once an as- cidian (when the ascidian was the highest form of life), may have been the best of the ascidians. This would, perhaps, add nothing to the present value of the race, but it might satisfy the Platonic demand that the race, though not derived from a source quite worthy of it, yet should come from the best in nature. j64. philosophical dlscusslons. We are thus led to the final problem, at present an appar- ently insoluble mystery, of the origin of the first forms of life on the earth. On this Mr. Darwin uses the figurative language of religious mystery, and speaks " of life with its several pow- ers being originally breathed by the Creator into a few forms or into one." For this expression Mr. Mivart takes him to task, though really it could mean no more than if the gravita- tive properties of bodies were referred directly to the agency of a First Cause, in which the philosopher professed to believe; at the same time expressing his unwillingness to make hypoth- eses, that is, transcendental hypotheses, concerning occult modes of action. But life is, indeed, divine, and there is grandeur in the view, as Mr. Darwin says, which derives from so simple yet mysterious an origin, and "from the war of nature, from fam- ine and death, the most exalted object which we are capable of conceiving, namely, the production of the higher animals." Mr. Mivart, however, is much more "advanced" than Mr. Darwin on the question of the origin of life or archigenesis, and the possibility of it as a continuous and present operation of nature. He admits what is commonly called "spontane- ous generation," believing it, however, to be not what in the- ology is understood by "spontaneous," but only a sudden production of life by chemical synthesis out of inorganic ele- ments. The absence of decisive evidence on this point does not deter him, but the fact that the doctrine can be reconciled to the strictest orthodoxy, and accords well with our author's theory of sudden changes in species, appears to satisfy him of its truth. The theory of Pangenesis, on the other hand, invented by Mr. Darwin for a different purpose, though not inconsistent with the very slow generation of vital forces out of chemical actions, — slow, that is, and insignificant compared to the normal actions and productions of chemical forces, — is hardly compatible with the sudden and conspicuous appear- ance of new life under the microscope of the observer. This theory was invented like other provisional theories, — like New- ton's corpuscular theory of light, like the undulatory theory of light (though this is no longer provisional), and like the chem- ical theory of atoms, — for the purpose of giving a material or THE GENESIS OF SPECIES. l6 5 visual basis to the phenomena and empirical laws of life in general, by embodying in such supposed properties the phe- nomena of development, the laws of inheritance, and the vari- ous modes of reproduction, just as the chemical theory of atoms embodies in visual and tangible properties the laws of definite and multiple proportions, and the relations of gaseous volumes in chemical unions, together with the principle of isomerism and the relations of equivalent weights to specific heats. The theory of Pangenesis presents life and vital forces in their ulti- mate and essential elements as perfectly continuous, and in great measure isolated from other and coarser orders of forces, like the chemical and mechanical, except so far as these are the necessary theatres of their actions. Gemmules, or vital mole- cules, the smallest bodies which have separable parts under the action of vital forces, and of the same order as the scope of action in these forces, — these minute bodies, though probably as much smaller than chemical molecules as these are smaller than rocks or pebbles, may yet exist in unorganized materials as well as in the germs of eggs, seeds, and spores, just as crys- talline structures or chemical aggregations may be present in bodies whose form and aggregation are mainly due to mechan- ical forces. And, as in mechanical aggregations (like sediment- ary rocks), chemical actions and aggregations slowly supervene and give in the metamorphosis of these rocks an irregular crysT talline structure, so it is supposable that finer orders of forces lying at the heart of fluid matter may slowly produce imperfect and irregular vital aggregations. But definite vital aggrega- tions and definite actions of vital forces exist, for the most part, in a world by themselves, as distinct from that of chemical forces, actions, and aggregations as these are from the mechan- ical ones of dynamic surface-geology, which produce and are embodied in visible and tangible masses through forces the most directly apparent and best understood; or as distinct as these are from the internal forces of geology and the masses of continents and mountain formations with which they deal; or as distinct again as these are from the actions of gravity and the masses in the solar system ; or, again, as these are from the unknown forces and conditions that regulate sidereal aggrega- i66 PHILOSOPHICAL DISCUSSIONS. tions and movements. And as to the size of the gemmules, the various orders of molecular sizes are limited in our powers of conception only by the needs of hypothesis in the representation of actual phenomena under visual forms and properties. Sir William Thomson has lately determined the probable sizes of chemical molecules from the phenomena of light, and experi- ments relating to the law of the "conservation of force." Ac- cording to these results, these sizes are such that if a drop of water were to be magnified to the size of the earth, its molecules, or parts dependent on the forces of chemical physics, would be seen to range from the size of a pea to that of a billiard-ball. But there is no reason to doubt that in every such molecule there are still subordinate parts and structures; or that, even in these parts, a still finer order of parts and structures exists, at least to the extent of assimilated growth and simple division. Mr. Darwin supposes such growths and divisions in the vital gemmules; but our author objects (p. 230) that, " to admit the power of spontaneous division and multiplication in such rudimentary structures seems a complete contradiction. The gemmules, by the hypothesis of Pangenesis, are the ultimate organized components of the body, the absolute organic atoms of which each body is composed; how then can they be divisi- ble? Any part of a gemmule would be an impossible (because less than possible) quantity. If it is divisible into still smaller organic wholes, as a germ-cell is, it must be made up, as the germ-cell is, of subordinate component atoms, which are then the true gemmules." But this is to suppose what is not im- plied in the theory (nor properly even in the chemical theory of atoms), that the sizes of these bodies are any more constant or determinate than those of visible bodies of any order. It is the order only that is determinate; but within it there may be wide ranges of sizes. A billiard-ball may be divided into parts as small as a pea, or peas may be aggregated into masses as large as a billiard-ball, without going beyond the order of forces that produce both sizes. Our author himself says afterwards and in another connection (p. 290), " It is possible that, in some minds, the notion may lurk that such powers are simpler and easier to understand, because the bodies they affect are so THE GENESIS OF SPECIES. 167 minute ! This absurdity hardly bears stating. .We can easily conceive a being so small that a gemmule would be to it as large as St. Paul's would be to us." This argument, however, is intended to discredit the theory on the ground that it does not tend to simplify matters, and that we must rest somewhere in "what the scholastics called 'substantial forms.'" But this criticism, to be just, ought to insist, not only that vital phe- nomena are due to "a special nature, a peculiar innate power and activity," but that - chemical atoms only complicate the mysteries of science unnecessarily; that corpuscles and undu- lations only hide difficulties; and that we ought to explain very simply that crystalline bodies are produced by " polarity," and that the phenomena of light and vision are the effects of "luminosity." This kind of simplicity is not, however, the purpose which modern science has in view; and, consequently, our real knowledges, as well as our hypotheses, are much more complicated than were those of the schoolmen. It is not impossible that vital phenomena themselves include orders of •forces as distinct as the lowest vital are from chemical phe- nomena. May not the contrast of merely vital or vegetative phenomena with those of se7isibility be of such orders ? But, in arriving at sensibility, we have reached the very elements out of which the conceptions of size and movement are con- structed, — the elements of the tactual and visual constructions that are employed by such hypotheses. Can sensibility and the movements governed by it be derived directly by chem- ical synthesis from the forces of inorganic elements? It is probable,, both from analogy and direct observation, that they cannot (though some of the believers in " spontaneous genera- tion" think otherwise); or that they cannot, except by that great alchemic experiment which, employing all the influences of nature and all the ages of the world, has actually brought forth most if not all of the definite forms of life in the last and greatest work of creative power. EVOLUTION BY NATURAL SELECTION.* The physical problem, proposed independently and almost simultaneously near the beginning of this century by three eminent men of genius, Goethe, Geoffroy St. Hilaire, and the elder Darwin, how animals and plants came to have the structures and habits that characterize them as distinct species, this question which was proposed in place of the teleolog- ical inquiry, why they were so produced, has now fairly be- come a simple question for scientific investigation. There is no longer any doubt that this effect was by some natural process, and was not by a formless creative fiat. Moreover, there scarcely remains any doubt that this natural process connects the living forms of the present with very different forms in the past; and that this connection is properly described in general terms as "descent with modification." The question has thus become narrowed down to the inquiry, What is the nature of this modification, or what are the causes and the modes of ac- tion by which such modifications have been effected ? This is a great step in scientific progress. So long as a doubt remained about the fact that such modifications have been ef- fected, and that present living forms are the results of them, the inquiry, how they were effected, belonged to the region of profitless speculation, — profitless except for this, that specu- lative minds, boldly laying aside doubts which perplex and impede others, and anticipating their solution, have often in the history of science, by preparing a way for further progress, greatly facilitated their actual solution. Difficulties and ques- tions lying beyond such doubts — walls to scale after outworks * Frotfi the North American Review, July, 1872. E VOL UTION BY NA TURA L SELECTION. 169 and ditches are passed — do not inspire the cautious with cour- age. And so the scientific world waited, though prepared with ample force of evidence, and hesitated to take the step which would bring it face to face with the questions of the present and the future. Darwin's " Origin of Species," by marshaling and largely reinforcing the evidences of evolution, and by can- didly estimating the opposing evidence, and still more by pointing out a way to the solution of the greatest difficulty, gave the signal and the word of encouragement which effected a movement that had long been impending. The "that," the fact of evolution, maybe regarded as estab- lished. The "how," the theory or explanation of it, is the problem immediately before us. Its solution will require many years" of patient investigation, and much discussion may be anticipated, which will doubtless sometimes degenerate into acrimonious disputes, more especially in the immediate future, while what may be called the dialectics of the subject are being developed, and while the bearings and the limits of views and questions are being determined, and conceptions and definitions and kinds of arguments appropriate to the discussion, are the subjects on which it is necessary to come to a common under- standing. It is highly desirable that this discussion should be as free as possible from mere personalities, and there is strong hope that it may be kept so through the manners and methods of procedure established by means of the experience which the history of modern science affords. That it is impossible, however, to avoid errors of this sort altogether, is evident from the provocations experienced and keenly felt by some of the noblest of modern students of science in the estab- lishment of theories in modern astronomy, and of theories in geology, to which may now be added the theory of evolution. That the further discussion of rival hypotheses on the causes and modes of evolution will profit by these older examples may be hoped, since there have grown up general methods of inves- tigation and discussion, which prescribe limits and precautions for hypothesis and inference, and establish rules for the con- duct of debate on scientific subjects, that have been of the greatest value to the progress of science, and will, if faithfully 170 PHILOSOPHICAL DISCUSSIONS. observed, doubtless direct the present discussion to a successful issue. These methods are analogous in their purposes to the gen- eral rules in courts of law, and constitute the principles of method in experimental philosophy, or in philosophy founded on the sciences of observation. They serve to protect an investigation, by demanding that it shall be allowed on cer- tain pretty strict conditions (in the conduct of experiments and observations, and in the formation and verification of hypotheses) to proceed without hindrance from prejudice for any existing doctrine or opinion. An investigation may thus start from the simplest basis of experience, and, for this purpose, may waive, yet without denying, any presumption or conclusion held in existing theories or doctrines. Again, these rules protect an investigation from a one-sided criticism or ex /prejudgment, since they demand of the criticism or judgment the same judicial attitude that is demanded of the investiga- tion. Advocacy, and especially the sort that is of essential value in courts of law, where two advocates are set against each other, each with the duty of presenting only what can be said for his own side, and where the same judge and jury are bound to hear both, is singularly out of place in a scientific discussion, unless in oral debate before the tribunal of a sci- entific society. Moreover, there are no burdens of proof in science. Such advocacy in a published work claiming scien- tific consideration is almost an offense against the proprieties of such discussions. To collect together in one place all that can be said for an hypothesis, and in another all that can be said against it, is at best a clumsy and inconvenient method of discussion, the natural results of which may best be seen in the present condition of theological and religious doctrines. These practical considerations are of the utmost importance for the attainment of the end of scientific pursuit; which is not to arrive at decisions or judgments that are probably true, but is the discovery of the real truths of nature, for which science can afford to wait, and for which suspended judgments are the soundest substitutes. No work of science, ancient or modern, dealing with prob- EVOLUTION BY NATURAL SELECTION. 171 lematic views and doctrines, has more completely conformed to these principles, or more fully justified them by its success, than the " Origin of Species." For its real or principal success has been in convincing nearly all naturalists, a majority of whom, at least, were still unconvinced, of the truth of the theory of evolution; and this has resulted from its obvious fairness and spirit of caution almost as much as from the pre- ponderance of the evidences for the theory when thus pre- sented. And the very same qualities of spirit and method governed the leading and more strictly original design of the work, which cannot, however, yet be said to be a complete success, namely, the explanatio?i of evolution by natural selec- tion. That Mr. Darwin himself is fully convinced of the truth of this explanation is sufficiently evident. He holds that natu- ral selection is the principal or leading cause in determining the changes and diversities of species, though not the only cause of the development of their characters. Conspicuously at the close of the Introduction in the first edition of the work, and in all subsequent editions, occur these words : "lam convinced that Natural Selection has been the most important, but not the ex- clusive, means of modification." That the work is not a merely dialectical performance is clear; and it is equally clear that in proportion to the strength of the author's conviction is his solicitude to give full and just weight to all valid objections to it. In this respect the work stands in marked contrast to much that has been written on the subject and in reply to it. Once to leave the vantage-ground of scientific method and adopt the advocate's ex parte mode of discussion almost neces- sitates a continuance of the discussion under this most incon- venient form. Mr. Mivart's " Genesis of Species," which we examined in this Review last July, though a conspicuous exam- ple of such a one-sided treatment of a proper scientific question, was by a writer so distinguished for his attainments in science that his criticism could not well be passed by without notice; and, having also the character of a popular treatise, it came within a wider province of criticism tha/ that of strictly scien- tific reviews. Our notice of his work was chiefly devoted to sup- plying something of what could be and had been said in favor I j2 PHILOSOPHICAL DISCUSSIONS. of the theory thus criticised, both by way of denning and de- fending it. We also followed the author to some extent into the consideration of a subject, namely, the general philosophical and theological bearings of this theory, which does not, we en t deavored to show, belong properly to the discussion, and ought to be kept in abeyance, so long, at least, as the laws of exper- imental philosophy are observed in the conduct of the inquiry. One of the first questions asked in past times in regard to phys- ical hypotheses, which have now become established theories or doctrines of science, was, if they were orthodox, or at least theistic; and the negative decision of this question by what was deemed competent authority determined temporarily and in a measure the fate of the hypothesis and the standing of those who held to it. It was to be hoped that, in the light of such a history, this discussion could be spared the question, at least till the hypothesis could be fairly tried, when, if it should be found wanting in scientific validity, its banishment to the limbo of exploded errors might, without much harm, be changed to a severer sentence ; and, if it should withstand the tests of purely scientific criticism, the same means of reconcil- ing it to orthodoxy would doubtless be found as in the case of older physical hypotheses. Mr. Mivart himself claimed and argued a similar exemption for the general theory of evolution, or rather attempted the later office of reconciliation, or the af- fording of proofs of its conformity to the most venerable and authoritative decisions of orthodoxy. But he appeared unwill- ing to allow either such an exemption, or the possibility of an accordance with orthodoxy, to the theory of natural selection, for he more than once quoted and applied to the discussion of this theory the saying and supposed opinions of an heretical heathen philosopher, Democritus. In his reply to our criticisms,* he wonders who could have so misled us as to make us suppose that his was a " theological education" and a "schooling against Democritus"; the fact being just the reverse of this, his education being in that ph-i- * See the number of the North American Review for April, 1872. Mr. Mivart has reprinted his reply, without notice of the present essay, in his volume entitled, "Les- sons from Nature," London, 1876. EVOLUTION BY NATURAL SELECTION. 173 losophy of "nescience," out Of the evils and fallacies of which he had at length struggled. Clearly we were misled by the author himself. Our error, slight except as a biographical one, would have been amended if we had referred the character of his criticism to his theological studies. This would have left the period in his life in which he acquired his mode of thought and discussion as undetermined, as it was unimportant to the point of our criticism; since, through the influence of these studies, or similar dialectical pursuits, his unquestionable abili- ties appeared to us to have been developed, and, as we believe, misapplied. It was the bringing in of "the fortuitous concourse of atoms," and "blind chance," "accidents," and "hap-hazard results," in a discussion with which they had no more to do, and no less, than they have to do with geology, meteorology, politics, philosophical history, or political economy. It was this irrelevancy in his criticism which we regarded as oblivious of the age in which we live and for which he wrote, — the age of experimental philosophy. Mr. Mivart thinks he is clear of all blame for speaking of the theory of natural selection as lia- ble "to lead men to regard the present organic world as formed, so to speak, accidentally, beautiful and wonderful as is confessedly the hap-hazard result," since he qualified the word "accidentally" by the phrase "so to speak." The real fault was in speaking so at all. Accidents in the ordinary every-day sense are causes in every concrete course of events, — in the weather, in history, in politics, in the market, — and no theory of these events can leave them out. Explanation of the events consists in show- ing how they will result, or have resulted, through certain fixed principles or laws of action from the occasions or opportunities, which such accidents present. Given the state of the atmos- phere over a large district in respect to temperature, moisture, pressure, and motion, — none of which could have been antici- pated without similar data for a short time before, all in fact being accidents, — and the physical principles of meteorology might enable us to explain the weather that immediately fol- lows. So with the events of history, etc. In no other sense are accidents supposed as causes in the theory of natural selec- 174 PHILOSOPHICAL DISCUSSIONS. X tion. Accidental variations and surrounding conditions of existence, and the previous condition of the organic world, (none of which could have been anticipated from anything we actually know, all in fact being "accidents") — these are the causes which present the occasions or opportunities through which principles of utility and advantage are brought to bear in changing structures and habits, and improving their adap- tations. If this is like the philosophy of Democritus, or any other excommunicated philosopher of antiquity, and is, there- fore, to be condemned for the heresy, then all the sciences with which we have compared it, and many others, the con- quests of human intelligence, must share the condemnation. We dwelt in our review, perhaps unnecessarily, on the fact that accidents in this sense, and in the theory of natural selec- tion, as well as elsewhere, are relative to our knowledge of causes; that the same event, like an eclipse of the sun, might be an accident to one mind, and an anticipated event to an- other. We did so because we could not understand otherwise why our author should single out the theory of natural selection from analogous theories and sciences for a special criticism of this sort; or except on the idea that the accidents in natural selection were supposed by him to be exceptional, and of the type which Democritus is reputed to have put in the place of intelligent design, or on the throne of Nous. We did not, as Mr. Mivart imagines, think him "ignorant that the various phenomena which we observe in nature have their respective phenomenal antecedents," nor suppose that he "held the opinion that phenomena of variation, etc., are not determined by definite, invariable, physical antecedents." We only thought that, knowing better,- — knowing that "natural selec- tion," like every other physical theory, dealt with physical causes and their laws, — he was unjust and inconsistent in con- demning the employment of it, as a leading or prominent cause, in explanation of the phenomena of the organic world, in the manner in which he did; except on the hypothesis, which we repudiated in behalf of experimental philosophy but without positively attributing it to him, — the hypothesis of absolute accidents. It was inconsistency and irrelevancy which we meant to attribute to him. E VOL UTION B Y NA TURA L SELECTION. J 75 That he supposed absolute accidents to be meant in the an- cient atheistical philosophy appeared from a passage in his chap- ter on Theology and Evolution (p. 276), in which he speaks of the kind of action we might expect in physical nature from a theistic point of view, as an action " which is orderly, which disaccords with the action of blind chance and with the ' fortui- tous concourse of atoms' of Democritus." But in his reply to us he repudiates the idea that this old philosophy held events to be accidental in the strict sense; and he further says of us that we "know very well that Democritus and Empedocles and their school no more held phenomena to be undetermined or unpreceded by other phenomena than do their successors at the present day." We are far from being so well informed, or willing to accept this as a statement of our views. For, in the first place, the terms "undetermined" and "unpreceded" are not synonymous. Moreover, so far as phenomena are deter- mined, they are "orderly," "harmonize with man's reason" (p. 275), though in their complexity they may be quite beyond the power of any man's imagination to represent or disen- tangle; and, as our author has said, they are what we might expect "from a theistic point of view." Whether Democritus believed in absolute accidents or not we do not know. Little is really known of his opinions in this respect. The question has been disputed, but not decided. All his works are lost, except a few quoted sentences and max- ims. He is in a peculiarly exposed condition for an attack from any one disposed to be his opponent. The words ascribed to him are unprotected by contexts, or by the scruples an oppo- nent might feel about their meaning were he assigning to him his place in the history of speculation. It is very likely that he did not hold to absolute accidents as occurring in the course of nature; though it is very doubtful whether he was so thoroughly convinced as his "successors of the present day" are of the universality of the "law of causation," or that every event must have determinant antecedents. The concep- tion of cause, as based by experimental science on the ele- mentary invariable orders of phenomenal successions, is, even at the present day, altogether too precise and abstract for the 176 PHILOSOPHICAL DISCUSSIONS. apprehension of a mind untrained by scientific studies. How much more so must it have been when among the old Ionian, philosophers the first crude conceptions of science were being fashioned by attempts at discovering the physical bond of union and the inchoate form of nature, regarded as a universe. It is an anachronism to speak of these philosophers as mate- rialists and atheists, since the distinctions and questions which could make such a classification intelligible had not yet been, proposed. And it is equally an anachronism to attribute even to later thinkers, like Democritus, such a conception of physical causation as only the latest and maturest products of scientific thought have rendered definite. There can be no antithesis in the problem of the beginning of the world between accident and law, that is, between accident and the orderly movements which imply determinant antece- dents. The real antithesis is between accident and miracle, that is, between accident and the extraordinary action of pre- existent designing intelligence; and in this relation Accident can only have an absolute meaning, equivalent in fact to Des- tiny or Fate, when unintelligible. Unintelligible Destiny or "blind chance" is directly opposed to the intelligible Destiny which is the principle of "law" in nature; though these have often been confounded as equally fatalistic and atheistical. Mr. Mivart, however, does not confound them; for he has said that the latter is what we might expect from a theistic point of view. It is altogether likely, however, that the Democritus to whom the former meaning could be attributed as a characteristic one is not the real thinker, but is a myth; or is rather the orthodox lay-figure of atheism of the theological studio. The reputation for atheism which the real Democritus doubt- less had may have come from a cause which has often pro- duced it in the history of physical science. He invented a theory of atoms with which he attempted physical explanations quite in advance of previous speculations. And the invention of physical hypotheses has often been regarded as an invasion of the province and jurisdiction of divine power and a first cause. For men rarely allow the explanation of any impor- tant effect in nature to remain an open question. If observed E VOL UTION BY NA TURA L SELECTION. 177 of inferred physical causes do not suffice, invisible or even spiritual ones are invented; and thus the ground is preoccu- pied, and closed against the inquiries of the physical phi- losopher. It is probably the general direction or tendency of these inquiries, rather than any positive positions or results at which they may arrive, which puts the physical philosopher in an apparently irreligious attitude. For in following out. the consequences of physical hypotheses into the details of natural phenomena, reasoning from supposed causes to their effects, his interests and his modes of thought are the reverse of those of mankind in general, and of the religious mind. He appears to turn his back on divinity, and though seeking to approach nearer the first cause, or the total order of nature, his aspect of looking downward from a proximate principle through a nat- ural order appears to the popular view to be darkened by a sombre shadow. The theory of universal gravitation was con- demned on this account for impiety by even so liberal and en- lightened a thinker as Leibnitz. This seems very strange to us now, since the law of gravitation is almost as familiar as fire, or even gravity itself. When in ancient times any one had burned his fingers, or been bruised by a fall, one did not, except perhaps in early childhood, attribute the harm to a person, a spirit, or a god, but to the qualities of fire or gravity; yet the sounds of the thunder were still referred directly to Zeus. We all remember how in the "Clouds" of Aristophanes the comic poet puts impiety in the mouth of Socrates, or the doc- trine that Zeus does not exist, and that it is ethereal Vortex, reigning in his stead, which drives the clouds and makes them rain and thunder. Such a view of physical inquiries is not confined to comic poets or their audiences. The meteorolog- ical sophists of that day were in very much the same position as the Darwinian evolutionists of the present time. However important it may be to bear these considerations in mind, there is, as we have said, no more occasion to do so with reference to the theory of natural selection than with reference to many other analogous theories, not only in physical science, like those of meteorology and geology (including the theory of evolution), but also in sociological science, like theories of po- I7 8 • PHILOSOPHICAL DISCUSSIONS. litical economy, and those theories of history which explain the growth of institutions, governments, and national charac- teristics. The comparison of the continuous order in time of the organic world and its total aspect at any period, to the pro- gressive changes and the particular aspect at any time of the weather, will, doubtless, strike many minds as inapt, since the latter phenomena are the type to us of indetermination and chance, while the former present to us the most conspicuous evidences of orderly determination and design. This con- trast, though conspicuous, is, nevertheless, not essential to the contrasted orders themselves. The movements in one are al- most infinitely slower than in the other. We see a single phase and certain orderly details in one. We see only confused and rapid combinations and successions in the other. One is seen in fine, the other in gross form. But looked at from the same point of view, regarding each as an ensemble of details in time and space, they are equally without definite order or intelligible plan; "beautiful and wonderful as is," according to Mr. Mivart, "the hap-hazard, result." It is in the intimate and comparatively minute parts of the organic world in individual structures or organisms that the beautiful and wonderful order is seen. When we look at great groups, like the floras and faunas of various regions, or at past geological groupings, — the shifting clouds, as it were, of organic life, — this order disap- pears or is hidden for the most part. There remains enough of apparent order to indicate continuity in time and space, but hardly anything more. Perfectly as the individual organism may exhibit adaptations or the applications of principles of utility, there is no definite clew in it to the cause of the partic- ular combination of uses which it embodies, or to its exist- ence in a particular region, or at a particular period in the his- tory of the world, or to its co-existence with many other quite independent particular forms. But in precise analogy with what is conspicuously regular and indicative of simple laws in the organic world, correspond the intimate elementary changes of the atmosphere, some of which, like the fall and even the formation of rain and snow, the development and disappear- ance of clouds, are almost as simple exhibitions of natural E VOL UTION BY NA TURAL SELE CTION. 179 laws as experiments in the laboratory. What, even in the laboratory, can exceed the beauty, simplicity, and complete- ness of that exemplification of definite physical laws which the fall of dew on clear, calm nights demonstrates ? More- over, there are in the successions of changes in the weather sufficient traces of order to indicate a continuity in space and time corresponding to the geographical distributions and geo- logical successions of the organic world. The elementary or- ders, which exhibit ultimate physical laws in simple isolation, are, in their aggregate and complex combination, the causes of the successions of changes in the weather and the source of whatever traces of order appear in them, and are thus analo- gous to what the theory of natural selection supposes in the organic world, namely, that the adaptations, or the exhibitions of simple principles of utility in structures, are in their aggre- gate and complex combinations the causes of successive and continuous changes in forms of life. Far more important, however, than such analogies in the doctrine of evolution is the clear understanding of what the theory of natural selection undertakes to explain, and what is the precise and essential nature of its supposed action. There appears to be much confusion on this subject, arising probably from the influence of preconceived opinions concern- ing the nature both of the matters explained and the mode of explanation, or, in other words, concerning the nature of the changes which take place in species and the relations of them to this cause. These would seem, at first sight, very simple matters for conception, and difficult only in the evidences and the adequacy of the explanation. Such appeared, and still appears, to be the opinion of Mr. Mivart. Perhaps the best way to make a difficult theory plain is the negative one of correcting the misconceptions of it as they arise. This is what we attempted in our former review with reference to the character of the variations from which nature normally and for the most part selects. But new difficulties have emerged in Mr. Mivart's later writings which deserve con- sideration. In his answer to Professor Huxley, in the January number of the "Contemporary Review" (p. 170), he says of I So PHILOSOPHICAL DISCUSSIONS. the theory of natural selection, "That the benefit of the indi- vidual in the struggle for life was announced as the one deter- mining agent, fixing slight beneficial variations into enduring characters," for which he thinks it quite incompetent. And again, in reply to us (p. 453), he speaks of " The origin, not, of course, of slight variations, but of the fixing of these in definite lines and grooves"; and this origin, he believes, can- not be natural selection. And we believe that his conclusions are right! That is, if the more obvious meaning of these expressions are their real ones. They appear to mean that natural selection will not account for the unvarying continu- ance in succeeding generations of simple changes made acci- dentally in individual structures (whether the change be large or small), or will not account for the direct conversion of a simple change in a parent into a permanent alteration of its offspring. Such is the apparent meaning of these expressions, but they might possibly be taken as loose expressions of the opinion that this cause will not account for permanent changes in the average characters, or mid-points, about which variations oscillate.; and, in this case, we believe that he is wrong. This permanency must not be understood, however, as meaning that changes cease, but only that they are not reversed. The same cause, natural selection, prevents such reversion, on the whole, and except in individual cases which it extermi- nates. The first and obviously intended meaning of these expres- sions has let in light upon the author's own theory and his gen- eral difficulty about the theory of natural selection, which we did not have before. They show how fundamentally the mat- ter has been misconceived, either by him or by us. That we did not more fully perceive this fundamental difference doubt- less arose from a tacit assumption of the principle of "specific stability " in his earlier criticisms, which was explicitly treated of in a later chapter and as a subordinate topic. This, as we shall find, is the source of the most serious misunderstanding. We were not aware that any one supposed that particular varia- tions ever became fixed and heritable changes in the characters of organisms by the direct agency of natural selection, or, in- EVOLUTION BY NATURAL SELECTION. j8i deed, by any other known cause. The proper effect of this cause is not to fix variations, though it must determine their averages and limit their range, and must act directly to in- crease the useful ones and diminish the injurious; or rather to permit the one and forbid the other, and when these are directly opposed to each other, it must act to shift the aver- age or normal character, instead of fixing it. Variation as a constant and normal phenomenon of organization, ex- hibited chiefly in the ranges of individual differences, is, as it were, the agitation or irregular oscillation that keeps the characters of species from getting too closely fixed in "definite lines and grooves," through the too rigid inheritance of ances- tral traits ; or it is a principle of alertness that keeps them ever ready for movement and change in conformity to changing con- ditions of existence. What fixes species (when they are fixed) is the continuance of the same advantages in their structures and habits, or the same conditions for the action of selection, together with the force of long-continued inheritance. This, though almost trite from frequent repetition, appears a very difficult conception for many minds, probably on account of their retaining the old stand-point of philosophy. It would appear that Mr. Mivart is really speaking of the fixed species of the old and still prevalent philosophy, or about real species, as they are commonly called. Natural selection cannot, of course, account for these figments. Their true explanation is in the fact that naturalists formerly assumed, without proper evidence, that a change too slow for them to perceive directly could not exist, and that characters widely prevalent and so far advanced as to become permanently adapted to very general and unchanging conditions of existence, like vertebral and articulate structures, the numbers and positions of the organs of locomotion in vari- ous animals, the whorl and the spiral arrangement of leaves in plants, and similar homological resemblances, could never have been vacillating and uncertain ones. It was not many years ago that a distinguished writer in criticising the views of Lamarck affirmed that "the majority of naturalists agree with Linnaeus in supposing that all the individuals propagated from one stock have certain distinguishing characters in common, 1 82 PHILOSOPHICAL DISCUSSIONS. which never vary, and which have remained the same since the creation of each species." The influence of this opinion still re- mains, even with naturalists who would hesitate to assert cate- gorically the opinion itself. This comes, doubtless, from the fact that long-prevalent doctrines often get stamped into the very meanings of words, and thus acquire the character of axioms. The word "species" became synonymous with real ox fixed species, or these adjectives became pleonastic. And this was from the mere force of repetition, and without valid foundation in fact, or confirmation from proper inductive evi- dence. Natural selection does not, of course, account for a fixity that does not exist, but only for the adaptations and the diver- sities in species, which may or may not be changing at any time. They are fixed only as the "fixed" stars are fixed, of which very many are now known to be slowly moving. Their fixity, when they are fixed, is temporary and through the acci- dent of unchanging external conditions. Such is at least the as- sumption of the theory of natural selection. Mr. Mivart's the- ory seems to assume, on the other hand, that unless a species or a character is tied to something it will run away; that there is a necessity for some internal bond to hold it, at least tempo- rarily, or so long as it remains the same species. He is enti- tled, it is true, to challenge the theory of natural selection for proofs of its assumption, that "fixity" is not an essential feature of natural species ; for, in fact, so far as direct evidence is con- cerned, this is an open question. Its decision must depend chiefly on the preponderance of indirect and probable evi- dences in the interpretation of the "geological record," a sub- ject to which much space is devoted, in accordance with its importance, in the " Origin of Species." Technical questions in the classification and description of species afford other evi- dences, and it is asserted by naturalists that a very large num- ber of specimens, say ten thousand, is sufficient, in some de- partments of natural history, to break down any definition or discrimination even of living species. Other evidences are afforded by the phenomena of variation under domestication. Mr. Mivart had the right, and may still have it, to resist all E VOL UTION B Y NA TURA L SELECTION. Y 8 3 this evidence, as not conclusive; but he is not entitled to call upon the theory of natural selection for an explanation of a feature in organic structures which the theory denies in its very elements, the fixity of species. This is what he has done, — implicitly, as it now appears, in his book, and explicitly in his later writings. The question of zoological philosophy, "Whether species have a real existence in nature/' in the decision of which nat- uralists have so generally agreed with Linnaeus, refers directly and explicitly to this question or the fixity of essential charac- ters, and to the assumption that species must remain unaltered in these respects so long as they continue to exist, or until they give birth to new species ; or, as was formerly believed, give place in perishing to new independent creations. The distinc- tion involved in this question in the word real should not be confounded, as it might easily be, with the distinction in Logic of "real kinds" from other class-names. Logic recognizes, a principal division in class-names, according as these are the names of objects which agree with each other and differ from other objects in a very large and indefinite number of particulars or attributes, or are the names of objects which agree only in a {