\ •] » QJornell Itttoeraitg lEihrarg Dtljata. New Sork BOUGHT WITH THE INCOME OF THE SAGE ENDOWMENT FUND THE GIFT OF HENRY W. SAGE 1891 Cornell University Library QP 85.M58 1910 The prolongation of life ; optimistic stu 3 1924 000 917 181 DATE DUE «l?»-^197l Uf m^/iv '6- PRINTED IN U.S.A. Cornell University Library The original of tiiis book is in tine Cornell University Library. There are no known copyright restrictions in the United States on the use of the text. http://www.archive.org/details/cu31924000917181 By ELIE METCHNIKOFF Sub-Director of the Pasteur Institute, Paris The Nature of Alan Studies in Optimistic Philosophy. Translated by P. Chalmers Mitchell. Octavo. Illustrated. Net, $2.00 The Prolongation of Human Life Optimistic Essays. Translated by P. Chalmers Mitchell. Octavo. Illustrated. Net, Sz.jo Popular Edition. . Net, ■$1.7^ Immunity in Infective Diseases Translated by Francis G. Binnie. Octavo. Illustrated. Net, SS-^J G. P. PUTNAM'S SONS NEW YORK LONDON THE PROLONGATION OF LIFE OPTIMISTIC STUDIES BY feLIE METCHNIKOFF SUB-DIRECTOR OF THE PASTEUR INSTITUTE, PARIS THE ENGLISH TRANSLATION EDITED BY P. CHALMERS MITCHELL M.A., D Sc. OxoN., Hon. LL.D., F.R.S. Secretary of the ZoSlogical Society of London; Corresponding Member of the Academy of Natural Sciences of Philadelphia POPULAR EDITION WITH AN INTRODUCTION BY CHARLES S. MINOT LL.D. (Yale, Toronto), D.Sc. (Oxford) James Stillman Professor of Comparative Anatomy in the Harvard Medical School President of the Boston Society of Natural History G. P. PUTNAM'S SONS NEW YORK & LONDON Ube Tftnicfterbocfter ipress 1910 '<«-/■•:*'« ■j'-.r. [ , ,yjO Sctx4 <>^' \/c--f. '^D^'c, A 5 I Copyright, igio BY G. P. PUTNAM'S SONS (Foi Introduction) QP Ms? Ube Itnfcfterboclier fftess, «ew ffiort INTRODUCTION TO THE AMERICAN EDITION OF 1910 BY CHARLES S. MINOT Elie Metchnikoff has done a remarkable amount of scientific investigation, the excellence of which is equally remarkable. Like Pasteur, he began in one field of re- search and, by the natural development of his studies, was led forward into a new field which at first seemed very remote from that which he formerly occupied. 'His earlier work dealt with problems of comparative embry- ology ; his later, with problems of disease. In accordance with these facts, his career divides itself into two parts, and, as if to emphasise this fact, we find that the earlier part was intimately associated with German influences and largely under their control, while the second part shows strong French influence and covers a time spent almost wholly in Paris. Metchnikoff was bom on May 3, 1845, ii^ar Kharkow iv INTRODUCTION in Russia, and was a student at the university there during 1862-64. He then went to Germany and studied zoology at the universities of Giessen, Gottingen, and Munich, for three years. This was the epoch when German zoologists felt the enormous stimulus of the Darwinian theory and were starting out upon many new lines of investiga- tion. The greatest interest was felt in the development of animals, and the study of embryology was expected to give many clews as to the evolution of animals.^ Many of the best minds were devoted to the pursuit of comparative embryology, which for a number of years held most ot the German naturalists under its spell and sway. Metchni- koff fell in at once with the prevailing trend, and devoted himself with the utmost industry and zeal to this branch of science. Memoir after memoir came from his pen in rapid succession, each constituting a valuable new contri- bution to knowledge. He studied almost every class of the lower animals and, had he never done any other work, he would rank permanently among the most distinguished zoologists of the nineteenth century. In 1870, he became professor at the University of Odessa, where he remained for twelve years, working actively all the time ; but in r882 he resigned his post. We may some day learn of the motives which led to that resignation. Under Russian conditions at that time, such action on the part of a man like Metchnikoff can- not surprise us. He then travelled about for a while visiting Madeira, Teneriffe, and the Volga, and worked at various places outside of Russia. It was during these years of wandering that he published his paper on the Intracellular Digestion in Invertebrate Animals. This was very important in itself and interesting to us as marking the transition from the pursuit of embryological to the pursuit of pathological science. The paper was published in the Arbeiten of the Zoological Institute INTRODUCTION v in Vienna, for the years 1883-84, and was translated into English and published in the Quarterly Journal of Microscopical Science, vol. xxiv., p. 89. The paper embodies the results of investigations on the process of digestion and absorption of food in various invertebrate animals. The author was led to this subject by its bear- ing upon certain problems of the evolution of animals, with which he was then occupied. He had reached the opinion that many questions connected with the genealogy of the higher animals are not to be solved by the methods of ordinary embryological study alone ; for these methods are chiefly concerned with the structure of organs which have lost their function by retrogression, or which, being not yet fully developed, have not acquired their full functional activity. Metchnikoff believed that a know- ledge of the physiological history of organs and tissues is indispensable to secure answers to the questions of evolu- tion. Accordingly he turned to the examination of one of the fundamental physiological processes, that of diges- tion. It was known that the lower animals, such as sponges, jelly-fishes, and certain worms, possess an in- tracellular digestion — that is to say, the digestive process is not carried on merely in digestive cavities, such as the stomach and intestines of higher animals, but within the actual living substance of the organism. This substance, as is well known, is divided up into elementary microscopic units, called cells. It had been demonstrated that, in the low animals referred to, particles of food are taken up into the interior of single cells and there digested. In the course of his studies, Metchnikoff discovered that in the interior of the bodies of these animals there are numerous cells capable of moving about by their own activity. These are the so-called wandering or amoeboid cells, which belong to that portion of the body designated by em- bryologists as the mesoderm. For example, he observed vi INTRODUCTION that in the larvas of certain echinoderms large numbers of amoeboid cells appear in the interior of the body and give rise to all the skeletal structures, the cutis of the adult, and the whole musculature of the larvas. Their function, however, is not purely morphogenetic, for at the period of metamorphosis — which is associated with the loss of many of the larval organs — the mesoderm cells ingest the cellular debris of the disappearing organs and finally absorb them. It is not difficult to watch the process of digestion and absorption of debris in. the single cell. The albuminpid granules of the disintegrating structures may remain for some time in contact with the amoeboid cells, and then be suddenly swallowed in the living protoplasm; or the swallowing process may be so gradual as to allow the various stages to be seen and drawn. The absorption, like the ingestion, of these granules varies greatly in rapidity. In these cases the material eaten by the mesbdermic cells has been formed from the body of the animal itself and has only become useless at the moment of its being devoured, but our author demonstrated that foreign particles could also be taken up in this way. He saw granules of carmine, suspended in water, pass into the body cells of jelly-fishes (Ctenophores) . He made a similar experiment with indigo. In pursuing his studies farther, Metchnikoff discovered that in these lower animals injurious foreign substances attracted the devouring cells and were gotten rid of. He recognised that he had discovered a natural means of protection against disease, for the presence of foreign substances in the tissues is often a disease, notably so if the foreign substance happens to be a collection of disease germs. Metchnikoff demonstrated that when for- eign particles are of an organic nature, they are actually digested by the amoeboid cells, and so entirely disappear. INTRODUCTION vii He concluded that the cells we are considering have im- portant protective functions. Iii the closing portion of his paper on intracellular digestion, he advanced the hypothesis that the middle portion of the body of animals (the mesoderm of embtyologists) was evolved primarily for the sake of these eating cells, and to supply the agents for the important processes of intracellular digestion. It will thus be seen that Metchnikoff was still working as an embryologist, but he had discovered that the amoeboid cells — for which he devised the name "phagocyte" — were able to protect the animal, so to speak, from internal enemies, and he clearly states that these agents must be regarded as having an important part to play as fighters against septic organisms, bacteria, etc., which may invade an animal's body. The recognition of the importance of phagocytes is due to Metchnikoff, and is a really great discovery, one which has become of immense practical importance to mankind chiefly, it must be added, through his own tireless studies of these cells in many different animals. Especially significant was his investigation of a fungus disease in certain small crustaceans belonging to the genus Daphne. These little creatures are abundant in fresh water and are quite transparent, so that the whole living animal can be readily studied under the microscope. Taking advantage of these favoiirable conditions, Metchnikoff was able not only to see the fungi inside of the animals, but also the phagocytes attacking them. He successfully demon- strated that the attacking cells take into their own pro- toplasmic bodies the parasitic fungi and digest them, thus destroying the parasite by which the Daphne was attacked, and the Daphne was thus partially or completely immune to the attacks.! ' For the researches on phagocytes in Daphne, see Virchow's Archiv, vol. g6, p. 177, and vol. 97, p. 502. viii INTRODUCTION Medical men, when they become scientific investiga- tors, are not infrequently hampered by the narrowness of their training. The vastness of medical knowledge offers embarrassing difficulties to the student, so that he may congratulate himself if he gets a reasonable degree of acquaintance and comprehension of human diseases, and may well be excused from attempting to include the whole animal kingdom in his survey; but the zoologist, with his different training, is more readily interested in comparative study, and we see in Metchnikoff the greatest instance of successful pathological research begun from the standpoint of the comparative zoologist, rather than from that of the physician. In 1892 the already famous Russian zoologist became chef de service at the Pasteur Institute, and after the death of Pasteur he was appointed Director of Scientific Researches, a position which he still holds. There he has been an industrious worker, accomplishing much himself, and directing other workers at the Institute. A large share of his attention and time has been devoted to the study of phagocytes in all classes of animals, including men. Two comprehensive volumes have been published by him, collating and reviewing the work which has been done by himself and others upon phagocytes, and espe- cially upon their activity as protective agents against germ diseases. The earlier and smaller of these works ap- peared in 1892, and was entitled Lessons on the Compara- tive Pathology of Inflammation, but his chef d'ceuvre was published in 1901, with the title L'Immunite, a work which has been accepted by pathologists throughout the world as an important standard classic. It has had a profound influence upon medical thought and practice. One feels safe in asserting that so great a monument of scientific ability would alone suffice to secure for Metchni- koff enduring fame. INTRODUCTION ix His scientific memoirs exhibit characteristics of a skilled and competent original investigator, with an un- usually well balanced temperament. His new observa- tions are found to have been made carefully and to have been sufficiently verified before they were published to the ,world. He has proved himself keen and alert in the interpretation of his observations, and his mind has been fruitful in suggestions and hypotheses which have stim- ulated further research, but which he has always kept apart from the direct and positive conclusions to be drawn from his discoveries. In debate he shows a rare serenity and equanimity, even in his early embryological writings — most of which were written and published in Germany, and differ honourably from many articles by Germans at that time, which were too frequently marred by acrid polemical discussions. One suspects that cheerfulness and optimism are in Metchnikoff inborn temperamental qualities, and in the present volume optimism is the dominant note. He presents here, with an attractive and clear style, some of the results of his work in science which most deserve the attention of the general public. The two works, which are now united in one Volume by the publishers, have made a very strong popular appeal and have already numerous readers. In addition to the strictly scientific chapters, there are others which present the general views of the author. Every thoughtful man finds towards the close of his career that, almost without planning, his mind has pro- duced for him a certain set of views as to the conditions of life and the objects of existence. He almost invariably assumes, as it were, an attitude towards life and its stand- ard problems, which have occupied the sages of all ages. It is not necessary that such a philosophy of life should be perfectly reasoned out, or that it should be based upon profound study in order to be very real and important X INTRODUCTION to its holder. It is such a system of views that Metchni- koff presents to us. The main theme of the present volume, however, is old age and the prolongation of life. It will be well for the unscientific reader to understand distinctly that Professor Metchnikoff does not offer a cure for old age. Old age is not a disease and cannot be cured; it is an accumula- tion of changes which begin during earliest youth and continue throughout the entire life of the individual. . To overcome old age, either the process or the result of the normal life of man would have to be radically changed, and there seems little prospect of our ever being able to overthrow the natural course of individual develop- ment. On the other hand, we may reasonably hope, by improving the health of the individual, to prolong life. Many measures have been taken in modern times which have contributed to the prolongation of life. Every danger of disease which is removed contributes to lengthen the lives of individuals. What Professor Metchnikoff offers for the treatment of old age is a method of nutrition which he believes will diminish the danger of old persons being attacked by those diseases to which they are es- pecially liable. Of course, as every medical man knows, new medical methods must be tried out thoroughly before their precise practical value can be determined. It is quite in accord with the scientific spirit, which has so nobly dominated Metchnikoff's life, that he with others at the Pasteur Institute is actively investigating the new method which he has devised, and which he describes in the present volume. It is reported that he has found fresh confirmation of his views. The publication of the new results will certainly be of wide interest. Professor Metchnikoff's style has a spontaneous charm, although he is writing, not in his mother tongue, but in French. The admirable English translation of Mr, INTRODUCTION xi Mitchell preserves this charm. After reading through the present work, one finds that the deepest impression re- ceived is that of the attractive character of the author. One feels that here is a man to whom hope is a habit of mind and who is very sanguine as to the happy future of mankind, which to him seems asstired by the progress of science. Harvard Medical School December, 1909 EDITOR'S INTRODUCTION Elie Metchnikoff has carried on the high purpose of the Pasteur Institute by devoting his genius for biological inquiry to the service of man. Some years ago, in a series of Essays which were intended to be provocative and educational, rather than expository, he described the direc- tion towards which he was pressing. I had the privilege of introducing these Essays to English readers under the. title The Nature of Man, a Study in Optimistic Philosophy. In that volume, Professor Metchnikoff recounted how sentient man, regarding his lot in the world, had found it evil. Philosophy and literature, religion and folk-lore, in ancient and modern times have been deeply tinged with pessimism. The source of these gloomy views lies in the nature of man itself. Man has inherited a constitution from remote animal ancestors, and every part of his struc- ture, physical, mental and emotional^ is a complex legacy of diverse elements. Possibly at one time each quality had its purpose as a'n adaptation to environment, but, as man, in the course of his evolution, and the environment itself have changed, the old harmonious intercourse between quality and circumstances has been dislocated in many cases. And so there have come into existence many instances of what the Professor calls " disharmony," per- sistences of structures, or habits, or desires that are no xiv EDITOR'S INTRODUCTION longer useful, but even harmful, failures of parallelism between the growth, maturity and decay of physical and mental qualities and so forth. Religions and philosophies alike have failed to find remedies or efficient anodynes for these evils of existence, and, so far, man is justified of his historical and actual pessimism. Metchnikoff, however, was able to proclaim himself an optimist, and found, in biological science, for the present generation a hope, or, at the least, an end towards which to work, and for future generations a possible achievement of that hope. Three chief evils that hang over us are disease, old age, and death. Modern science has already made vast strides towards the destruction of disease, and no one has more right to be listened to than a leader of the Pasteur Institute when he asserts his confidence that rational hygiene and preventive measures will ultimately rid man- kind of disease. The scientific investigation of old age shows that senility is nearly always precocious and that its disabilities and miseries are for the most part due to pre- ventable causes. Metchnikoff showed years ago that there exists in the human body a number of cells known gener- ally as phagocytes, the chief function of which is to devour intruding microbes. But these guardians of the body may turn into its deadly enemies by destroying and replacing the higher elements, the specific cells of the different tissues. The physical mechanism of senility appears to be in large measure the result of this process. Certain substances, notably the poisons of such diseases as syphilis and the products of intestinal putrefaction, stimulate the activity of the phagocytes and so encourage their encroachment on the higher tissues. The first business of science is to re- move these handicaps in favour of the wandering, cor- roding phagocytes. Specific poisons must be dealt with EDITOR'S INTRODUCTION xv separately, by prevention or treatment, and it is well known that Metchnikoff has made great advances in that direc- tion. The most striking practical side of The Nature of Man, however, was the discussion of the cause and pre- vention of intestinal putrefaction, Metchnikoff believes that the inherited structure of the human large intestine and the customary diet of civilised man are specially favourable to the multiplication of a large number of microbes that cause putrefaction. The avoidance of alcohol and the rigid ex- clusion from diet of foods that favour putrefaction, such as rich meats, and of raw or badly cooked substances con- taining microbes, do much to remedy the evils. But the special introduction of the microbes which cause lactic fer- mentation has the effect of inhibiting putrefaction. By such measures Metchnikoff believes that life will be greatly prolonged and that the chief evils of senility will be avoided. It may take many generations before the final result is attained, but, in the meantime, great amelioration is possible. There remains the last enemy, death. Metch- nikoff shows that in the vast majority of cases death is not " natural," but comes from accidental and preventable causes. When diseases have been suppressed and the course of life regulated by scientific hygiene, it is probable that death would come only at an extreme old age. Metch- nikoff thinks that there is evidence enough at least to suggest that when death comes in its natural place at the end of the normal cycle of life, it would be robbed of its terrors and be accepted as gratefully as any other part of the cycle of life. He thinks, in fact, that the instinct of life would be replaced by an instinct of death. Metchnikoff's suggestion, then, was that science should be encouraged and helped in every possible way in its task of removing the diseases and habits that now prevent xvi EDITOR'S INTRODUCTION human life from running its normal course, and his belief is that were the task accomplished, the great causes of pessimism would disappear. In this new volume. The Prolongation of Life, the main thesis is carried further, and a number of criti- cisms and objections are met. The latter, so far as they relate to technical details, I need say nothing of here, as Metchnikoff and his staff at the Pasteur Institute are the most skilled existing technical experts on these matters, but Icanhot refrain from a word of comment on the bril- liant treatment of the objection to the suggested ameliora- tion of human life that it considered only the individual and neglected the just subordination of the individual to society. In the sixth Part of this volume, Metchnikoff dis- cusses the relation of the individual to the species, society or colony, from the general point of view of comparative biology, and shows that as organisation progresses, the • integrity of the individual becomes increasingly important. Were orthobiosis, the normal cycle of life, attained by human beings, there still would be room for specialisation of individuals and for differentiation of the functions of individuals in society, but instead of the specialisation and differentiation making individuals incomplete throughout their whole lives, they would be distributed over the different periods of the life of each individual. As these lines are intended to be an introduction, not a commentary, I will now leave the reader to follow the argument in the book itself. P. Chalmers Mitchell. London, August, 1907. PREFACE It is now four years since I wrote a volume, the English translation of which was called The Nature of Man, and which was an attempt to frame an optimistic conception of life. Human nature contains many very complex elements, due to its animal ancestry, and amongst these there are some disharmonies to which our misfortunes are due, but also elements which afford the promise of a happier human life. My views have encountered many objections, and I wish to reply to some of these by developing my arguments. This was my first task in this book, but I have also brought together a series of studies on problems which closely affect my theory. Although it has been possible to support my conception by new facts, some of which have been established by my fellow-workers, others by myself, there still remain many sides of the subject where it is necessary to fall back on hypotheses. I have accepted such imperfections instead of delaying the publication of my book. Even at present thfere are critics who regard me as in- capable of sane and logical reasoning. The longer I post- pone publication, the longer would I leave the field open to such persons. What I have been saying may serve also XVlll PREFACE as a reply to the remark of one of my critics, that my ideas have been " suggested by self-preoccupation." It is, of course, quite natural that a biologist whose atten- tion had been aroused by noticing in his own case the phenomena of precocious old age should turn to study the causes of it. But it is equally plain that such a study could give no hope of resisting the decay of an organism which had already for many years been growing old. If the ideas which have come out of my work bring about some modi- fication in the onset of old age, the advantage can be gained only by those who are still young, and who will be at the pains to follow the new knowledge. This volume, in fact, like my earlier one on the "Nature of Man," is directed much more to the new generation than to that which has already been subjected to the influence of the factors which produce precocious old age. I think that thus the experience of those who have lived and worked for long can be made of service to others. As this volume is a sequel to The Nature of Man, I have tried as much as possible to avoid repetition of what was fully explained in the earlier volume. Here I bring together the results of work that has been done since the publication of The Nature of Man. Some of the chapters relate to subjects upon which I have lec- tured, or which, in a different form, have been printed before. For instance, the section on the psychic rudiments of man appeared in the Bulletin cle I'Institut general ■psycho- logique of 1904, the essay on Animal Societies was pub- lished in the Revue Philomatique de Bordeaux et du Sud- Ouest of 1904, and in the Revue of J. Finot of the same year, whilst a German translation of it appeared in Prof. Ostwald's Annalen der Naturphilosophie. The chapter on soured milk first appeared as a pamphlet, published in PREFACE xix 1905. The substance of my views on natural death was published in June last in " Harper's Monthly Magazine" of New York, while the chapter on natural death in animals appeared in the first number of the Revue du Mois for 1906. I have to thank most sincerely the friends and pupils who have helped me by bringing before me new facts, or other materials; the names of these will appear in their proper places in the volume. I have not mentioned by name, however. Dr. J. Goldschmidt, whose continual en- couragement and practical sympathy have made my work much easier. Finally, my special thanks are due to Drs. Em. Roux and Burnet, and M. Mesnil, who have been so good as to correct my manuscript and the proofs of this volume. E. M. Paris, J^'ed. 7, 1907. CONTENTS Editor's introduction Preface .... PAGE xiii xvii PART I THE INVESTIGATION OF OLD AGE I THE PROBLEMS OF SENILITY Treatment of old people in uncivilised countries. — Assassination " of old people in civilised countries. — Suicide of old people. — Public assistance in old age. — Centenarians. — Mme. Robineau, a lady of 106 years of age. — Principal characters of old age. — Examples of old mammals. — Old birds and tortoises. — Hypothesis of senile degeneration in the lower animals i II THEORIES OF THE CAUSATION OF SENILITY Hypothesis of the causation of senility. — Senility cannot be attributed to the cessation of the power of reproduction of the cells of the body. — Growth of the hair and the nails in old age. — Inner mechanism of the senescence of the tissues. — Notwithstanding the criticisms of M. Marinesco, the neuronophags are true phagocytes. — The whitening of hair, and the destruction of nerve cells as arguments against a theory of old age based on the failure of the reproductive powers of the cells 15 III MECHANISM OF SENILITY Action of the macrophags in destroying the higher cells. — Senile degeneration of the muscular fibres. — Atrophy of the xxii CONTENTS PACE skeleton. — Atheroma and arterial sclerosis. — ^Theory that Old Age is due to alteration in the vascular glands. — Organic tissues that resist phagocytosis . . . • 25 PART II LONGEVITY IN THE ANIMAL KINGDOM I THEORIES OF LONGEVITY Relation between longevity and size. — Longevity and the period of growth. — Longevity and the doubling in weight after birth. — Longevity and rate of reproduction.- — Probable rela- tions between longevity and the nature of the food . . 39 II LONGEVITY IN THE ANIMAL KINGDOM Longevity in the lower animals. — Instances of long life in sea- anemones and other vertebrates. — Duration of life of insects. — Duration of life of " cold-blooded " vertebrates. — Dura- tion of life of birds. — Duration of life of mammals. — Inequality of the duration of life in males and females. — Relations between longevity and fertility of the organism . 47 III THE DIGESTIVE SYSTEM AND SENILITY Relations between longevity and the structure of the digestive system. — The caeca in birds. — ^The large intestine of mam- mals. — Function of the large intestine. — The intestinal microbes and their agency in producing auto-intoxication and auto-infection in the organism. — Passage of microbes through the intestinal wall 59 IV MICROBES AS THE CAUSE OF SENILITY Relations between longevity and the intettinal flora. — Rumi- nants. — ^The horse. — Intestinal flora of birds. — Intestinal flora of cursorial birds. — Duration of life in cursorial birds. — Flying mammals. — Intestinal flora and longevity of bats. — Some exceptions to the rule. — Resistance of the lower vertebrates to certain intestinal microbes • • . 73 CONTENTS xxiii DURATION OF HUMAN LIFE Longevity of man. — ^Theory of Ebstein on the normal duration of human life. — Instances of human longevity. — Circum- stances which may explain the long duration of human life 84 PART III INVESTIGATIONS ON NATURAL DEATH I NATURAL DEATH AMONGST PLANTS Theory of the immortality of unicellular organisms. — Examples of very old trees. — Examples of short-lived plants. — Pro- longation of the life of some plants. — Theory of the natural death of plants by exhaustion. — Death of plants from auto- intoxication 94 II NATURAL DEATH IN THE ANIMAL WORLD Different origins of death in ^animals. — Examples of natural death associated with violent acts. — Examples of natural death in animals without digestive organs. — Natural death in the two sexes. — Hypothesis as to the cause of natural death in animals 109 III NATURAL DEATH AMONGST HUMAN BEINGS Natural death in the aged. — Analogy of natural death and sleep. — ^Theories of sleep. — Ponogenes. — The instinct of sleep. — ^The instinct of natural death. — Replies to critics. — Agreeable sensation at the approach of death . . .119 PART IV SHOULD WE TRY TO PROLONG HUMAN LIFE? I THE BENEFIT TO HUMANITY Complaints of the shortness of our life. — Theory of " medical selection " as a cause of degeneration of the race. — Utility ^ of prolonging human life ....... 132 xxiv CONTENTS PAGE II SUGGESTIONS FOR THE PROLONGATION OF LIFE Ancient methods of prolonging human life. — Gerokomy. — The " immortality draught " of the Taoists. — Brown-S^quard's method. — The spermine of Poehl. — Dr. Weber's precepts. — Increased duration of life , in historical times. — Hygienic maxims. — Decrease in cutaneous cancer .... 13' III DISEASES THAT SHORTEN LIFE Measures against infectious diseases as aiding in the prolonga- tion of life. — Prevention of syphilis. — Attempts to prepare serums which could strengthen the higher elements of the organism 145 IV INTESTINAL PUTREFACTION SHORTENS LIFE Uselessness of the large intestine in man. — Case of a woman whose large intestine was inactive for six months. — Another case where the greater part of the large intestine was com- pletely shut oft. — Attempts to disinfect the contents of the large intestine. — Prolonged mastication as a means of pre- venting intestinal putrefaction 151 V LACTIC ACID AS INHIBITING INTESTINAL PUTREFACTION The development of the intestinal flora in man. — Harmlessness of sterilised food. — Means of preventing the putrefaction of food. — Lactic fermentation and its anti-putrescent action. — Experiments on man and mice. — Longevity in races which used soured milk. — Comparative study of different soured milks. — Properties of the Bulgarian Bacillus. — Means of preventing intestinal putrefaction with the help of microbes 161 PART V PSYCHICAL RUDIMENTS IN MAN I RUDIMENTARY ORGANS IN MAN Reply to critics who deny the simian origin of man. — Actual existence of rudimentary organs. — Reductions in the struc- CONTENTS XXV PAGE ture of the organs of sense in man. — Atrophy of Jacobson's organ and of the Harderian gland in the human race . . 184 II HUMAN TRAITS OF CHARACTER INHERITED FROM APES The mental character of anthropoid apes. — Their muscular strength. — Their expression of fear. — The awakening of latent instincts of man under the influence of fear . .191 III SOMNAMBULISM AND HYSTERIA AS MENTAL RELICS Fear as the primary cause of hysteria. — Natural somnambulism. — Doubling of personality. — Some examples of somnam- bulists. — Analogy between somnambulism and the life of anthropoid apes. — ^The psychology of crowds. — Importance of the investigation of hysteria for the problem of the origin of man 200 PART VI SOME POINTS IN THE HISTORY QF SOCIAL ANIM.^LS I THE INDIVIDUAL AND THE RACE Problem of the species in the human race. — Loss of individuality in the associations of lower animals. — Myxomycetes and Siphonophora. — Individuality in Ascidians. — Progress in the development of the individual living in a society . .213 II INSECT SOCIETIES Social life of insects. — Development and preservation of indi- viduality in colonies of insects. — Division of labour and sacrifice of individuality in some insects .... 220 III SOCIETY AND THE INDIVIDUAL IN THE HUMAN RACE Human societies. — Differentiation in the human race. — Learned women. — Habits of a bee, Halictus quadricinctus. — Co!- lectivist theories. — Criticisms by Herbert Spencer and xxvi CONTENTS PAGE ^ Nietzsche. — Progress of individuality in the societies of higher beings 223 PART VII PESSIMISM AND OPTIMISM I PREVALENCE OF PESSIMISM Oriental origin of pessimism. — Pessimistic poets. — Byron. — Leopardi. — Poushlvin. — Lermontoff. — Pessimism and suicide 233 II ANALYSIS OF PESSIMISM Attempts to assign reasons for the pessimistic conception of life.-^Views of E. von Hartmann. — Analysis of Kowalev- sky's work on the psychology of pessimism .... 239 III PESSIMISM IN ITS RELATION TO HEALTH AND AGE Relation between pessimism and the state of the health. — History of a man of science who was pessimistic when young and who became an optimist in old age. — Optimism of Schopenhauer when old. — Development of the sense of life. — Development of the senses in blind people. — The sense of obstacles 247 PART VIII GOETHE AND FAUST I GOETHE 'S YOUTH Goethe's youth. — Pessimism of youth. — Werther. — ^Tendency to suicide. — Work and love. — Goethe's conception of life in his maturity 261 11 GOETHE AND OPTIMISM Goethe's optimistic period.— His mode of life in that period.— Influence of love in artistic production.— Inclinations towards the arts must be regarded as secondary sexual char- CONTENTS xxvii PAGE acters. — Senile love of Goethe. — Relation between genius and the sexual activities . . ^. . . . . zyo III Goethe's old age > Old age of Goethe. — Physical and intellectual vigour of the old man. — Optimistic conception of life. — Happiness in life in his last period 279 IV GOETHE AND " FAUST " Faust the biography of Goethe. — ^The three monologues in the first Part. — Faust's pessimism. — The brain-fatigue which finds a remedy in love. — ^The romance with Mar- guerite and its unhappy ending 283 THE OLD AGE OF FAUST The second Part of Faust is in the main a description of senile love. — Amorous passion of the old man. — Humble attitude of the old Faust. — Platonic love for Helena. — The old Faust's conception of life. — His optimism. — ^The general idea of the play 290 PART IX SCIENCE AND MORALITY I UTILITARIAN AND INTUITIVE MORALITY Difficulty of the problem of morality. — Vivisection and anti-vivi- section. — Enquiry into the possibility of rational morality. — Utilitarian and intuitive theories of morality. — Insufficiency of these 301 II MORALITY AND HUMAN NATURE Attempts to found morality on the laws of human nature. — Kant's theory of moral obligation. — Some criticisms of the Kantian theory. — Moral conduct must be guided by reaspn 309 xxviii CONTENTS in INDIVIDUALISM Individual morality. — History of two brothers brought up in the same circumstances, but whose conduct was quite different. — Late development of the sense of life. — Evolution of sym- pathy. — The sphere of egoism in moral conduct. — Christian morality. — Morality of Herbert Spencer. — Danger of exalted altruism . . IV ORTHOBIOSIS Human nature must be modified according to an ideal. — Com- parison with the modification of the constitution of plants and of animals. — Schlanstedt rye. — Burbank's plants. — The ideal of orthobiosis. — The immorality of ignorance. — The place of hygiene in the social life. — The place of altru- ism in moral conduct. — The freedom of the theory of orthobiosis from metaphysics THE PROLONGATION OF LIFE PART I THE INVESTIGATION OF OLD AGE I THE PROBLEMS OF SENILITY Treatment of old people in uncivilised countries — Assassina> tion of old people in civilised countries — Suicide of old people — Public assistance in old age — Centenarians — Mme. Robineau, a lady of io6 years of age — Principal characters of old age — Examples of old mammals: — Old birds and tor- toises — Hypothesis of senile degeneration in the lower animals In the ' ' Nature of Man " I laid down the outlines of a theory of the actual changes which take place during the sen- escence of our body. These ideas, on the one hand, have raised certain difficulties, and, on the other, have led to new investigations. As the study of old age is of great theoretical importance, and naturally is of practical value, I think that it is useful to pursue the subject still further. Although there exist races which solve the difficulty of old age by the simple means of destroying aged people, the problem in civilised countries is complicated by our more refined feelings and by considerations of a general nature. In the Melanesian Islands, old people who have become incapable of doing useful work are buried alive. In times of famine, the natives of Tierra del Fuego kill and eat the old women before they touch their dogs. 2 THE PROLONGATION OF LIFE When they were asked why they did this, they said that dogs could catch seals, whilst old women could not do so. Civilised races do not act like the Fuegians or other savages ; they neither kill nor eat the aged, but none the less life in old age often becomes very sad. As they are incapable of performing any useful function in the family or in the village, the old people are regarded as a heavy burden. Although they cannot be got rid of, their death is awaited with eagerness, and is never thought to come •soon enough. The Italians say that old women have seven lives. According to a Bergamask tradition, old women have seven souls, and after that an eighth soul, quite a little one, and after that again half a soul ; whilst the Lithuanians complain that the life of an old woman is so tough that it cannot be crushed even in a mill. We may take it as an echo of such popular ideas that murders of old people are extremely common even in the most civilised European countries. I have been astonished in looking through criminal records to see how many cases there are of the murder of old people, specially of old women. It is easy to divine the motives of these acts. A convict of the Island of Saghalien, condemned for the assassination of several old persons, declared naively to the prison doctor : "Why pity them? They were already old, and would have died in any case in a few years." In the celebrated novel of Dostoiewsky, " Crime and Punishment," there is a tavern scene where young people discuss all sorts of general topics. In the middle of the conversation a student declares that he would " murder and rob any cursed old woman without the least remorse." " If the truth were told," he goes on to say, "this is how I look at the thing. On the one hand a stupid old woman, childish, worthless, ill-tempered, and in bad health ; nq one would miss her, indeed she is a nuisance to evervone. She THE PROBLEMS OF SENILITY 3 does not even herself know any reason why she should live, and perhaps to-morrow death will make a good rid- dance of her. On the other hand, there are fresh and vigorous young people who are dying in their thousands, in the most senseless way, no one troubling about them, and everywhere the same thing is going on." Old people not only run the risk of murder; they very often end their own lives prematurely by suicide. They prefer death to a life oppressed by material hard- ships or burdened by diseases. The daily papers give many instances of old people who, tired of suffering, asphyxiate themselves by their charcoal stoves. The frequency of suicide in the case of the old has been established by numerous statistics, and the new facts which I now cite do no more than confirm it. In 1878, in Prussia, amongst 100,000 individuals there were 154 cases of suicide of men between the ages of 20 and 50, but 295, that is to say, nearly twice as many of men between the ages of 50 and 80. In Denmark, a country in which suicide is notoriously common, a similar proportion exists. Thus, in Copenhagen, in the ten years from 1886 to 1895, there were 394 suicides of men between 50 and 70. These figures relate to 100,000 individuals. Of the suicides 36J per cent, were those of people in the prime of life, 63J per cent, those of the aged.^ In such circumstances, it is natural that politicians and philanthropists have made many attempts to ameliorate the old age of the poor. In some countries laws have been passed to bring about this. For instance, a Danish law of June 27th, i8gi, established compulsory aid for the aged, enacting that every person more than 60 years old was to have the legal right to aid if required. In 1896 more than 36,000 people (36,246) were pensioned ^ Westergaard, Mortalitaet u. Morbilitaet, 2nd. Edit., 1901, pp. 653-655. B 2 4 THE PROLONGATION OF LIFE under this law, at a cost of nearly ;^200,ooo. In Belgium, the indigent old people are not pensioned until they reach the age of 65. In France, until recently, the aged poor could be supported at the public expense only by prosecut- ing them and sending them to prison for begging. This state of affairs, however, ceased with the application of the law of July 15th, 1905, according to which any French subject without resources, unable to support himself by work, and either more than 70 years of age, or suffering from some incurable infirmity or disease, is to receive public assistance. It has been thought the proper course to make such laws, and to lay the burden on the general population, without inquiring if it may not be possible to retard the debility of old age to such an extent that very old people might still be able to earn their livelihood by work. Old age can be studied by the methods of exact science, and there may yet be established some regimen by which health and vigour will be preserved beyond the age where now it is generally necessary to resort to public charity. With this object, a systematic investigation of senescence should be made in institutions for the aged, where there are always a large number of people from 75 to 90 years old, although centenarians are extremely rare. I know many institu- tions for aged men where, from their first foundation, there has been no case of an inhabitant reaching the age of 100, and even in similar institutions for women, although women live to much greater ages than men, centenarians are very rare. At the Salpetri^re, for instance, where there is always a large number of old women, it is the rarest chance to find a centenarian. Opportunity for the study of the extremely aged is to be found only in private families. THE PROBLEMS OF SENILITY 5 Most of the centenarians whom I have been able to see have been so defective mentally that all that can be studied in them are the physical qualities and functions. A few years ago an old woman who had reached her looth year was the pride of the Salpetri^re. She was bedridden and extremely feeble physically and mentally. She replied briefly when she was asked questions, but apparently with- out any idea of what they meant. Not long ago, a lady who lived in a suburb of Rouen reached her looth birthday. The local newspapers wrote exaggerated articles about her, praising the integrity of her mind and her physical strength. I paid a visit to her myself, hoping to make a detailed investigation, but I found at once that the journalists had completely misrepre- sented her condition. Although her physical health was fairly good, her intelligence had degenerated to such an extent that I had to abandon the idea of any serious inves- tigation. The most interesting of all the centenarians with whom I have become acquainted had reached an extremely advanced age, having entered upon her 107th year. It is about two years ago that a journalist, Monsieur Flamans, took me to see this Mme. Robineau who lived in a suburb of Paris. I found her a very old-looking lady, rather short, thin, with a bent back, and leaning heavily on a cane when she walked. The physical condition (Mme. Robineau was born on January 12th, 1800), of this woman of more than 106 years, showed extreme decay. She had only one tooth ; she had to sit down after every few steps, but, once comfortably seated, she could remain in that position for quite a long time. She went to bed early and got up very late. Her features displayed very great age (see Fig. i), although her skin was not extremely wrinkled. THE PROLONGATION OF LIFE ail, a CL-nlcnanan. From a photograph taken on hei one hundrcil and fifth hirthday. The skin of her hands had become so transparent that one could see the bones, the blood-vessels, and the tendons. Her senses were very feeble; she could see only with one eye ; taste and smell were extremely rudimentary ; her hear- THE PROBLEMS OF SENILITY 7 ing was her best means of relation with the external world. None the less, Dr. Lowenberg, a well-known aurist, had assured himself that her auditory organs showed in a most marked degree, the usual signs of old age, such as complete insensibility to high notes and slight deafness for low notes. Dr. Lowenberg attributed these changes to senile degeneration, of the ear which affected more and more seriously the nervous mechanism although it had caused little change in the conducting apparatus. Notwithstand- ing her physical weakness, Mme. Robineau retained her intelligence fully, her mind remained delicate and refined and the goodness of her heart was touching. In contrast with the usual selfishness of old people, Mme. Robineau took a vivid interest in those around her. Her conversation was intelligent, connected, and logical. Examination of the physical functions of this old lady revealed facts of great interest. Dr. Ambard found that the sounds of the heart were normal, but perhaps a little accentuated. The pulse was regular, 70 to 84 a minute, and its tension was normal. The arterial pressure was 17. The lungs were sound. ^11 these facts testify to her general health. The most remarkable circumstance was the absence of sclerosis of the arteries, although such degeneration is usually believed to be a normal character of old age. Analysis of the urine, made on several occasions, showed that the kidneys were affected with a chronic disease, which, however, was not serious.^ Although the sense of taste was weak, Madame Robineau ' The volume of the urine excreted in 24 hours (in January 1905) was 500 c.c, with a density of 1019. There was no albumen or sugar. The quantity, per litre, of urea was ii"5o gr., of chlorides 9 gr., of phosphates i'i5 gr. The sediment contained crystals of uric acid, some pavement epithelium cells, a very few cells from the tubules, some hyaline platelets and isolated white corpuscles. 8 THE PROLONGATION OF LIFE had a fair appetite. She ate and drank , little, but her diet was varied. She took butcher's meat or chicken ex- tremely seldom, but ate eggs, fish, farinaceous food, vege- tables, and stewed fruit, and drank sweetened water with a little white wine, and sometimes, after a meal, a small glass of dessert wine. The processes of alimentary diges- tion and excretion were normal. It has sometimes been thought that duration of life is a hereditary property. There was no evidence for this in the present case. Madame Robineau's relatives had. died comparatively early in life, and a centenarian was unknown in her family. Her great age was an acquired character. Her whole life had been extremely regular. She had married a timber merchant, and had lived for many years in a suburb of Paris in comfortable circum- stances. Her character was gentle and affectionate; she was thoroughly domesticated, and had been devoted to home life with very few distractions. At the age of io6 years, her intelligence suddenly became weak. She lost her memory almost completely, and some- times wandered. But her gentle and affectionate disposi- tion remained unaltered. The appearance of aged persons is too well known to make detailed description necessary. The skin of the face is dry and wrinkled and generally pale; the hairs on the head and the body are white; the back is bent, and the gait is slow and laborious, whilst the memory is weak. Such are the most familiar traits of old age. Baldness is not a special character; it often begins during youth and naturally is progressive, but if it has not already appeared, it does not come on with old age. The stature diminishes in old age. As the result of a series of observations, it has been established that a man THE PROBLEMS OF SENILITY 9 loses more than an inch (3" 166 cm.), and a woman more than an inch and a half (4"3 cm.), between the ages of fifty and eighty-five years. In extreme cases, the loss may be nearly three inches. The weight also becomes less. According to Qu^telet, males attain their maximum weights at the age of forty, females at that of fifty. From the age of sixty years onwards, the body becomes lighter, the loss at eighty being as much as thirteen pounds. Such losses of height and weight are signs of the general atrophy of the aged organism. Not merely the soft parts, such as the muscles and viscera, but even the bones lose weight, in the latter case the loss being of the mineral constituents. This process of decalcification makes the skeleton brittle, and is sometimes the cause of fatal acci- dents. The loss of muscular tissue is specially great. The volume diminishes, and the substance becomes paler; the fat between the fibres is absorbed, and may disappear completely. Movements are slower, and the muscular force is abated. This progressive degeneration has been examined by dynamometrical measurements of the hand and the trunk, and is greater in males than in females. The volumes and weights of the visceral organs simi- larly become smaller, but the diminution is not uniform. The old age of lower mammals presents characters similar to those found in man. I can now give other instances than the case of the old dog which I described in the " Nature of Man." I will first take the case of old elephants, described by a competent observer. "The general appearance is wretched, the skull being often hardly covered with skin ; there are deep abrasions under the eyes, and smaller ones lO THE PROLONGATION OF LIFE on the cheeks, whilst the skin (if the forehead is very often deeply fissured or covered with lumps. The eyes are usually dim, and discharge an abnormal quantity of water. The margin of the ears, speciall}- on the lower side, is usually frayed. The skin of the trunk is rougli- ened, hard, and warty, so that the organ has lost much of its flexibility. The skin on the body generally is worn and wrinkled; the legs are thinner than in maturity, the *T^^ ■^■^fT~Tj' -!7J:^Ji■-^!-■4■ ^^^ Ji#»t^.:j Fig. 2. — A ivUnc, thin)"-3cven }'tjars old. huge mass of muscles being much shrunken, whilst the circumference, especialh' just above the feet, is consider- ably reduced. The skin round the toe-nails is roughened and fra\'ed. The tail is scaly and hard, and the tip is often hairless. Horses begin to grow old much sooner than elephants. 1 reproduce (Fig. 2) the photograph of a rare instance of longevit}', a mare 37 years old, which belonged to M. THE PROBLEMS OF SENILITY 1 1 M6taine, in the department of Ma)'enne. The skin, bare in places, but elsewhere covered with long hairs, shows considerable atroph\-. The general attitude reveals the feebleness of the whole body. Many birds, on the ether hand, show at similar ages \'er_v slight external change, as may be seen from the photograph (jf a duck more than 25 vears old (Fig. 3) which belonged to Dr. Jean Charcot. At a still greater age, as may be seen occasionally in parrots, b IG. 3. — A While Duck, which lived for more than a quarter of a century. the general del)ilit\- of the bod)- re\-eals itself in the atti- tude, in the condition of the feathers, and in the swelling of the joints. On the other hand, the oldest reptiles which have been observed do not differ in appearance from normal adults of the same species. I ha\e in my posses- sion a male tortoise (Testudo uiauritaiiica) given me by my friends AIAF Rabaud and Caullery, and which is at least 86 years old. It shows no sign of old age, and in 12 THE PROLONGATION OF LIFE all respects behaves like any other individual of this species. More than 31 years ago it was wounded by a blow, the traces of which remain visible on the right side of the carapace {P\g. 4). In the last three years the tortoise lived in a garden at Montauban, along with two females which laid fertile eggs. The old male, although, as I have said, probably at least 86 years of age, was still sexually healthy. I have borrowed from the interesting volume of Prof. Sir E. Ray Lankester ^ the figure (Fig. 5) and de- FlG. 4. — An Old Ijand-lortoisc. scription of a giant tortoise from the island of Mauritius, which is probably the oldest of all living animals. It was brought to Mauritius from the Seychelles in 1764, and has lived since then in the garden of the Governor, and as it lias thus already been 140 years in captivity, its age must be at least 130 years, although we have not exact information. Notwithstanding this, it shows no signs of old age. The examples which I have brought together show that * Extinct Animals^ London, 1905, pp. 28, 29. THE PROBLEMS OF SENILITY 13 often amongst vertebrates there are some animals the organ- isms of which withstand the ravages of time much better than that of man. I think it a fair inference that senihty, the precocious senescence which is one of the greatest sorrows of humanity, is not so profoundly seated in the constitution of the higher animals as has generally been supposed. It is not necessary, therefore, to discuss at 1 ! J 1 m ^ 1 J f 1-* ft; ■ ^ i. Fig. 5. — A Water-lortoise, mere than 150 yeara old. (After Prof. Sir E. Ray Lankester. | length the general question as to whether senile degenera- tion is an inevitable event in living organisms. I have already shown, in the " Nature of Man," the differ- ence which exists between senile degeneration in our own bodies and the phenomena of senescence amongst In- fusoria which, as M. Maupas described, are followed by a process of rejuvenescence. According to the more recent results of several investigators, the difference is still greater than I had supposed. Enriquez ' has been able ' Rendiconti d. Accad. d. Lincei, 1906, vol. xiv. pp. 351, 390. 14 THE PROLONGATION OF LIFE to propagate Infusoria to the 700th generation without any sign of senility being displayed. Here we are far from the condition in the human race. R. Hertwig/ one of the best observers of the lower animals, has recently attempted to show that the very simple animalculae of the genus Actinosphaerium are subject to true physiological degeneration . He has several times seen cultures of this Rhizopod degenerate, until all the individuals had died, notwithstanding the presence of abundant food. Prof. Hertwig attributed this to the " con- stitution of the Actinosphaerium having been weakened by too great vital activity at an earlier stage." I should have thought that it was a much more natural explanation to suppose that the culture had undergone infection by one of the contagious diseases which so often destroy cultures of different kinds of lower animals and plants. As this idea had not occurred to the observer, he had not searched for parasitic microbes amongst the granulations which are always present in the body of an Actinosphaerium. How- ever this may be, I cannot accept the facts brought forward by this distinguished German as a valid proof of the exist- ence of senile degeneration in these lowly creatures. The facts that I have brought together in this chapter justify the conclusion that human beings who reach ex- treme old age may preserve their mental qualities notwith- standing serious physical decay. Moreover, it is equally plain that the organism of some vertebrates is able to resist the influence of time much longer than is the case with man under present conditions. ' Ue6. d. physiologische Degeneration bei Actinosphaerium eichhornii. Jena, 1904. II THEORIES OF CAUSATION OF SENILITY Hypothesis of the causation of senility — Senility cannot be attributed to the cessation of the power of reproduction of the cells of the body- — Growth of the hair and the nails in old age — Inner mechanism of the senescence of the tissues — Notwithstanding the criticisms of M. Marinesco, the neurono- phags are true phagocytes — The whitening of hair and the destruction of nerve cells, as arguments against a theory of old age based on the failure of the reproductive powers of the cells Although it has not been proved that living matter must inevitably undergo senile decrepitude, it is none the less true that man and his nearest allies generally exhibit such degeneration. It is therefore extremely important to recog- nise the real causes of our senescence. There have been many hypotheses on the subject, but there are compara- tively few definite facts known. Biitschli has supposed that the life of cells is maintained by a specific vital ferment which becomes feebler in pro- portion to the extent of cellular reproduction, but I cannot regard this as more than a pious opinion. The ferment has never been seen, and we do not know of its actual existence. According to the better-known theory of Prof. Weismann, old age depends on a limitation in the power of cells to reproduce, so that a time comes when the body can no longer replace the wastage of cells which is an 1 6 THE PROLONGATION OF LIFE inevitable accompaniment of life. As old age appears at different times in different species and different indivi- duals, Weismann has concluded that the possible number of cell generations differs in different cases. He has not found, however, a solution of the problem as to why multi- plication of cells should cease in one individual, whereas it proceeds much further in other individuals. Prof. Minot,^ the American zoologist, has developed a similar theory, and has employed an exact method to determine the gradual diminution in the rate of growth of an animal from its birth onwards. According to him, the power of reproduction of the cells weakens progressively during life, until a point is necessarily reached at which the organism, no longer capable of repairing itself, begins to atrophy and degenerate. Dr. Buehler ^ has recently laid stress upon this theory. There is no doubt that cells reproduce much more actively during the embryonic period. The process becomes slower later on, but, none the less, continues to, display itself throughout the whole period of life. Buehler attributes the difficulty with which certain wounds heal in the case of old people to the insufficiency of cellular reproduc- tion. He thinks in particular that the proliferation of the cells of the skin, to replace those which are worn off from the surface, becomes less active with age. According to him, it is theoretically obvious that a time must come when the replacement of the epidermic cells completely ceases. As the superficial layers of the skin continue to dry up and be cast off, it is plain that the epidermis must disappear completely. Buehler thinks that there must be • " Senescence and Rejuvenation," Journal of Physiology, 1891, t. xil. * Biologisches Centralblatt, 1904, pp. 65, 81, 113. THEORIES OF CAUSATION OF SENILITY 17 a similar fate for the genital glands, the muscles, and all the other organs. These theoretical considerations, however, are not com- patible with certain well-known facts indicating that there is no general cessation of the power of cell reproduction in old age. The hairs and the nails, which are epidermic outgrowths, continue to grow throughout life, their growth being due to the proliferation of their constituent cells. There is no sign of any arrest in the development of these structures, even in the most advanced old age. The reverse is true. It is well known that the hairs on some parts of the body increase in number and in length in old people. In some lower races, for instance in the Mongols, the moustache and the beard grow vigorously in old age, whilst young people of the same race have only very small moustaches and practically no trace of beard. So also in white women the fine and almost invisible down which covers the upper lip, the chin, and the cheeks in the young may become replaced by long hairs which form a mous- tache or beard. Dr. Pohl, a specialist in the growth of hair, has measured the rate of growth in different circumstances. He has shown that in an old man of 61 the hair on the temple grew II mm. in a month; on the other hand, the hair on the same region in boys of 11 to 15 years old grew in the same time only from 11 to 12 mm. Plainly, there is no case here of a progressive diminution of cell-proliferation with age. The same observer, it is true, has shown that the hair of young men of between 21 and 24 years grew at the rate of 15 mm. a month, whilst in the same individuals, at the age of 61 years, the rate of growth was only 1 1 mm. ; but this diminution in the rate of growth is only apparent. The first figure concerned the hair taken from different c 1 8 THE PROLONGATION OF LIFE regions of the scalp, whilst the second related only to the hair on the temples, and Dr. Pohl himself has shown that, in the latter region, the hair grows slower than in other regions. Moreover, in many boys of ii to 15 years old, studied by this observer, the rate of growth was always less than 15 mm., and often less even than the 11 mm. recorded in the old man of 61. I have been able to note that the nails grow even in very old people. In the case of Mme. Robineau, the centena- rian, the nail of the middle finger of the left hand grew 2j mm. in three weeks. In the case of a lady of 32 years old, the corresponding nail grew 3 mm. in two weeks, the difference being out of all proportion .to the enormous difference in the age. The centenarian's nails had to be cut from time to time. Although the hairs of old people grow, they become white, which is a phenomenon of senile degeneration. Although they increase in length, the colouring matter in them becomes reduced and finally disappears. In the " Nature of Man " I described the process by which this blanching takes place, and which may now be regarded as definitely proved. It is useful as a means of interpreting the real nature of the process of senescence. In several published works, I have explained my belief that just as the pigment of the hair is destroyed by phagocytes, so also the atrophy of other organs of the body, in old age, is very frequently due to the action of devouring cells which I have called macrophags. These are the phagocytes that destroy the higher elements of the body, such as the nervous and muscular cells, and the cells of the liver and kidneys. This part of my theory has encountered very strong criti- cism, especially with regard to the part played by the macrophags in the senescence of nervous tissue. THEORIES OF CAUSATION OF SENILITY 19 Neurologists in particular, have criticised my interpreta^ tion. For several years M. Marinesco' has attacked my theory of the atrophy of the nerve-cells in old age. In the first place, he has stated that in old people, and even if these are very old, it is rare to find phagocytes surrounding and devouring the tells of the brain. In support of this contention, he has been good enough to send me two pre- parations made from the brains of two very old persons. After careful examination I was convinced that my oppo- nent had been inexact. In the brain of the two centenarians (one of whom died at the age of 1 17 years) there were very many nerve-cells surrounded by phagocytes and in process of being destroyed by them. It happened, however, that as the sections were very weakly stained, it was more diffi- cult to observe the facts than in the preparations upon which I had made my own observations. I have already recorded this fact in the second and third French editions of the " Nature of Man." Without taking notice of my reply, M. Marinesco has published another criticism of my theory in an article* entitled " Histological Investigations into the Mechanism of Senility." In that work, although he himself had invented the designation " neuronophag " for a phagocyte that devours nerve-cells, he denies the existence of such a power. He thinks that nerve-cells atrophy independently of the cells that surround them. The latter, the so-called neur- onophags, only contribute to the atrophy inasmuch as they press against the nerve-cells and deprive them of nutrition. He is confident that the constituent parts of nerve-cells are never found in the neuronophags. There is no question of ' Comftes rendus de lAcaddmie des sciences, 23 April, 1900. " Revue ginirale des sciences, 30 Dec, 1904, p. 11 16. c a 20 THE PROLONGATION OF LIFE phagocytosis, of the existence of cells that devour their neighbours. M. L6ri has taken a similar view in a Report on the Senile Brain ^ presented to a recent congress of alienists and neurologists. According to him "the nuclei which surround some of the atrophying nerve-cells do not play the part of neuronophags." In his monograph " La Neuronophagie,"^ M. Sand elaborates the same view. He relies on his observation that " neuronophags are usually either devoid of protoplasm or display only a very thin layer of it. They never exhibit protoplasmic outgrowths, and they never have granules in their cellular bodies (p. 86)." Still more recently MM. Laignel-Lavastine and Voisin '' have taken the same view, maintaining that the neurono- phags do not display phagocytosis. Although I cannot undertake here to give a detailed reply to the arguments of my critics, I may point out a fallacy that vitiates their reasoning. The study of the intimate structure of nervous tissue involves the treatment of that very delicate substance by numerous active reagents. It is extremely important not to forget the possibility of altera- tions which may be produced in the processes of preparation and which are extremely difficult to avoid. A glance at the figures given by my critics shows me that the neurono- phags in their preparations had been subjected to violent treatment. When M. L^ri speaks of "the nuclei which surround some of the nerve-cells," and M. Sand of " cells without protoplasm," it is clear that they had been observ- ing cells destroyed by the processes of the laboratory. The 1 Le Bulletin medical, 1906, p. 721 ; Le Cerveau sMle, Lille, igo6, pp. 64-69. 2 Mimoires couronnds publiis par tAcadimie royale de Belgique, Bruxelles, igo6. ' Revue de Mddecine, Nov., 1906, p. 870. THEORIES OF CAUSATION OF SENILITY 21 illustrations in the memoir of M. Marinesco show that in his preparations, too, the neuronophags had been very greatly altered. It is well known that nuclei do not exist free in tissues, and that when they appear devoid of protoplasm, there has . been some defect in the technical methods of preparing them for examination. As a matter of fact, neuronophags do not consist of nuclei with at the most a pellicle of proto- plasm ; like other cells, they have protoplasmic "bodies which, however, are frequently destroyed by the violent processes of histological preparation. The arguments of my critics recall to me the words of a medical student, who, on being asked to describe the microbe of tuberculosis, said that it was a little red bacillus. The bacillus in question, like most bacilli, is colourless, but it is usual to stain it so that it may be visible under the microscope. The student, knowing it only in particu- ' lar preparations, had a false idea of its appearance. In well-made preparations, neuronophags are typical cells with abundant protoplasm. When they have been pre- served by a process that does not dissolve their contents, they show granules like those found in nerve-cells. To study neuronophagy, M. Manou61ian,^ in the labora- tory of the Pasteur Institute in Paris, set himself to improve the technical methods of preparation. He succeeded in showing first that in the destruction of nerve-cells that occurs in cases of hydrophobia, the contents of these cells are absorbed by the surrounding neuronophags. " My observations on the cerebro-spinal ganglia of human cases of hydrophobia," he wrote, " show clearly that the macro- phags act as phagocytes of the nerve-cells." " Most of the cells in the nerve-ganglia contain yellow, brown, and black ' Annates de Ulnstitut Pasteur^ Oct. 1906, p. 859. 22 THE PROLONGATION OF LIFE pigmented granules, usually united in small masses. What becomes of these granulations on the destruction and dis- appearance of the nerve-cell? If, as M. Marinesco has it, there is no phagocytosis by the surrounding cells, but merely a mechanical interference, then the granules, on the destruction of the nerve-cells that contained them, should be found lying in the interstitial tissue. But this does not happen. The granules are ingested by cells virhich are true macro'phags." By the aid of a very delicate mode of preparation, M. Manoudian has shown that in the case of senile brains the granules of the nerve-cells are absorbed by neurono- phags. I have myself studied M. Manouelian's prepara- tions and can testify to the accuracy of his observations (Figs. 6 and 7). Doubt is no longer possible. In senile degeneration the nerve-cells are surrounded by neuronophags which absorb their contents and bring about more or less complete atrophy. It has been supposed that in order to devour their contents, the neuronophags must penetrate the nerve-cells, and such an event has rarely been seen. But it is well known, the phagocytosis of red blood corpuscles being a typical instance, that to absorb a cell a phagocyte does not necessarily engulf it bodily or penetrate it, but may gradu- ally denude it of its contents merely by resting in contact with it. There has been some discussion as to the condition of nerve-cells which are on the point of being devoured bv neuronophags. It has been noticed that such cells may display a considerable amount of degeneration without being devoured, whilst, on the other hand, cells apparently normal have been found undergoing phagocytosis. As I cannot state definitely what are the conditions that induce THEORIES OE CAUSATION OF SENILITY 23 the phagoc\-tosi<; of nerve-cells, I shall not attempt a dis- cussion of the problem. Althou,£:h the destruction of nerve-cells bv neuronophags is a general occurrence in senile brains, one may conceive of cases where this does not occur. And so, in old people who have preserved their faculties, it may well be that the neuronophags have refrained from attacking the nerve-cells. 0f^r. '^y Fig. 6. Figs. 6. & 7. — Two nerve-cells from ihe corte.x of llie brain of an old dog aged fifteen years. The neuronophags surrounding the nerve-cells contain numerous granulations. (From preparations made by M. Wanouelian.) But as such instances are rare, so also phagocytosis is usually found in senile brains, and I cannot accept i\l. Sand's denial of its existence, based on his study of two cases. The general result of mv investigation into the criticisms that have been publishc^d 1)0 this matter has confirmed me in my belief that neuronophagy plays a most important 24 THE PROLONGATION OF LIFE part in senescence, and recent observations that I have made with M. Weinberg have completely supported this view. The bleaching of hair and the atrophy of the brain in old age thus furnish important arguments against the view that senescence is 'the result of arrest of the reproduc- tive powers of cells. Hairs grow old and become white without ceasing to grow. The cessation of the power of reproduction cannot be the cause of the senescence of brain- cells, for these cells do not reproduce even in youth. Ill MECHANISM OF SENILITV Action of the macrophags in destroying the higher cells — Senile degeneration of muscular fibres — Atrophy of the skele- ton — ^Atheroma and arterial sclerosis — Theory that old age is due to alteration in the vascular glands^ — Organic tissues that resist phagocytosis The instances which I have selected in attempting to describe the mechanism of senescence of the tissues are not the only cases in which the importance of phagocytosis is evident. The blanching of hair is due to the destructive agency of chromophags; in atrophy of the brain neur- onophags destroy the higher nerve-cells. In addition to these instances of phagocytosis, in which the active agents belong to the category of macrophags, there are many other devouring cells, adrift in the tissues of the aged, and ready to cause destruction of other cells of the higher type. The phagocytic action is not so manifest as in the case of infec- tious diseases, partly because it is the method of macro- phags to absorb the contents of the higher cells extremely slowly. The mode of action is well seen in the atrophy of an egg-cell (Fig. 8), where the surrounding macrophags gradually seize hold of the granules within it and carry these off. As the process goes on, the ovum becomes reduced to a shapeless mass^ and finally leaves only a few 26 THE PROLONGATION OF LIFE fraqrnents, or disappears completely. M. Matchinsky ' has studied the series of events in mv laboratory, and I am myself well assured of the importance of the action of macrophags in the atrophy of the ovary. The phenomena of atrophy in general and of senile decay afford other cases of tissue destruction in which the phago- t'iG. 8. — Ovum of a bitch in process of rlestruction by I'hagocytes, which are full of faU)' i^ranules. (After M. Afatchinsky.) cytic character of the process is more modified and obscure than in nerve-cells and ova. It is well known that progressive muscular debility is an accompaniment of old age. Phvsical work is seldom given to men over sixty years of age, as it is notorious that they are less capable of it. Their muscular movements are feebler and soon bring on fatigue; their actions are slow and painful. Even old men whose mental vigour is un- impaired admit tfieir muscular weakness. The physical ' Annali's de Flnstitut Pasteur, igoo, vol. xiv. p. 113. MECHANISM OF SENILITY 27 correlate of this condition is an actual atrophy of the muscles, and has for long been known to observers. More than half a century ago, Kolliker,^ one of the founders of histology, devoted some attention to this matter, and described the senile modification of muscular tissue in the following words : — " In old age there is a true atrophy of the muscles. The fibres are much more slender; there are deposited in their substance numerous yellow or brown granules and many globular nuclei. These nuclei are fre- quently arranged in longitudinal series and present such signs of active division as are found in embryonic tissue." Other investigators afterwards made similar observations. Vulpian^ and Douaud* have stated that a multiplication of nuclei takes places in the atrophying muscles of the old. As the senile degeneration of muscular tissue appeared to be important in my study of the mechanism of senescence, M. Weinberg and I e!xamined several cases of muscular atrophy in old human beings and lower animals. We were able to recognise the phenomena observed by our prede- cessorso In senile atrophy the muscular fibres contain many nuclei, and these, increasing rapidly, bring about an almost complete disappearance of the contractile substance (Fig. 9). The fibres preserve their striation for a certain time but eventually lose it and appear to contain an amor- phous mass with numerous, rapidly multiplying nuclei. The investigators who had recorded these facts thought of them only as curious. It is plain, in the first place, however, that this remarkable and rapid multiplication is a proof that senile atrophy is not due to failure of cell pro- * EUments dhistologie humaine, French translation, 1856, p. 222. ^ Leqons sur la physiologic du sy slime nerveux, 1 866. ' De la degendrescence graisseuse des muscles ckez des vieillards, Paris, 1867. 28 THE PROLONGATION OF LIFE liferati(jn, although iln' latter has fret|uently been suggested as the mechanism nl si-n(-scence. In muscular atrophy, cell- multipHcation, so far from faihng, greati}' increases. We may add muscular atrophy to the blanching of hair and the decay of nerve-cells as another instance showing that senile degeneration is not the result of cells ceasing to be able to Fig. 9. — Degeneration <>[ striated iriuscie Fibres from the auricular muscle of a man aged 87 years. (f>um a preparation made by Dr. Weinberg.) multiply. Just as in the atrophy of the brain there is an increase in the \'olume of neuroglixa, the substance in which the neuronophags are found, scj als(j in the atrophy of the muscles there is an increase of muscular nuclei. Along with the increase of nuclei, however, there is an increase of the protoplasmic substance of the fibres known as sarco- plasm. The latter replaces the myoplasm, the specific striated substance of muscles, b\' a process which must be ■ MECHANISM OF SENILITY 29 regarded as parallel with phagocytosis. In a normal muscle the two substances and the sarcoplasmic nuclei are in equilibrium, but in old age the sarcoplasm and its nuclei increase at the expense of the myoplasm. The equilibrium is destroyed with the result that the muscular power is weakened. In these conditions the sarcoplasm acts phago- cytically with regard to the myoplasm, just as the chromo- phag becomes the phagocyte of the pigment of the hair, or the neuronophag devours the nerve-cell. The investigation of other cases of muscular atrophy, as, for instance, that of the caudal muscles of frog-tadpoles, confirms the significance of the process that I have observed in old age. In the two cases, what takes place is the destruction of the contractile material of the muscles by myophags, a special kind of phagocyte. , It is one of the curiosities of senile atrophy that whilst there is hardening or sclerosis of so many organs, the skele-, ton, the most solid part of our frame-work, becomes less dense, so that the bones are friable, the condition .often leading to serious accidents in old people. The bones become porous, and lose weight. It is difficult to believe that macrophags, although they destroy softer elements such as nerve-cells or muscle fibres, can be able to gnaw through a . hard material like bone impregnated with mineral salts. As a matter of fact, the mechanism of bone atrophy must be placed in a different category from the phagocytosis of other organs. It is brought about, how- ever, by the agency of cells very like some of the macro- phags. These cells contain many* nuclei, and are known as osteoclasts. They form round about the bony lamella and lead to their destruction, but are incapable of breaking off fragments of bone and dissolving them in their interiors. Although the intimate mechanism of this destructive action 3° THE PROLONGATION OF LIFE IS not thorouglily undtTstood, it seems probable that the cells secrete some acid which softens bone by dissoh'ing the lime salts. The process can be obser\-ed in the dilTerent varieties of caries of tlie bone, and in the l^ony atrophy of old age as is represented in Fig. lo. By the action of the osteoclasts, which themselves are macrophags, part of the lime in the skeleton is dissolved during old age and passes into the general circulation. This is probabl}' a source of the lime A\hich is deposited so readily in the different tissues of old people. "Whilst the bones become lighter, the cartilages become bony, the inter- X'-c'^'^^V Fig. io. — Destruction Ijy osteoclasts of bony matter ni the ^tcnium ol a nian aged Si years. (From a jireparation made by Dr. WeinVjerg. ) vertebrate discs in particular becoming impregnated with salts, so that the well-known senile malformation of the backbone is produced. As a result of this displacement of lime in old age, the blood-vessels become modified in a distinctive fashion. .Atheroma of the arteries is n(:)t in\ariablc in old people, but it occurs extremely frequenth'. In this form (jf degenera- tion, lime salts are deposited in the walls til the cells, so that the}' become hard and friable. Se\'eral others, among whom I may mention Durand-P'ardel and Sauvage, have laid stress on the coincidence ()f atheromatous lesions of the arteries and senile degeneration of the bones. The relations MECHANISM OF SENILITY 31 between the two alterations are very evident in the skull ; the meningeal artery becomes sinuous and atheromatous, and the grooves on the inner side of the bones of the skull in which it runs, flatten out, and become larger because of other malformations.^ There is no disharmony in the nature of old people so striking as this transference of the lime salts from the skeleton to the blood-vessels, producing as it does a danger- ous softening of the former, and a hardening of the latter that interferes with their function of carrying nutrition to the organs. It is the manifestation of an extraordinary disturbance of the properties of the cells that compose the body. The atheromatous condition of the arteries is closely linked with arterial sclerosis, an affection which is very common, although hot constant, in the aged. The whole question of these vascular alterations is extremely complex, and before it can be cleared up, a number of special inves- tigations must be made. Probably diseases of the arteries of different kinds, and arising from different causes, are grouped under the terms atheroma and sclerosis. In some cases the lesions are in- flammatory and- are due to the poisons of microbes. An example of such an origin is the case of syphilitic sclerosis, in which the specific microbes (spirilla of Schaudinn) lead to precocious senescence. In other cases the arteries show phenomena of degeneration resulting in the formation of calcareous platelets which interfere with the circulation of the blood. Investigations which have been made in recent years have led to very interesting results concerning the origin of atherorna of the arteries. In most cases, attempts to produce such lesions of the arteries by experimental 1 Demange, itude sur la vieillesse, 1886, p. 1 18. 32 THE PROLONGATION OF LIFE methods have not succeeded, but M. Josu^^ has been able to produce true arterial atheroma in rabbits by injecting into them adrenaline, the secretion of the suprarenal cap- sules. This experiment has been repeated many times and is now well known. Later on, M. Boveri^ obtained a similar result by injecting nicotine, the poison of tobacco. It is obvious, therefore, that amongst the arterial diseases which play so great a part in senescence, some are chronic inflam- mations produced by microbes, whilst others are brought about by poisons introduced from without. It is easy to understand, therefore, why these diseases of the arteries are not always present in old age, although they are very common. The part played by the secretion of the suprarenal glands in the production of arterial disease has brought renewed attention to a theory which supposed that certain glandular organs in the body play a preponderating part in senile degeneration. Dr. Lorand* in particular has argued that " senility is a morbid process due to the degeneration of the thyroid gland and of other ductless glands which normally regulate the nutrition of the body." It has long been noticed that persons affected with myxodema, as a result of the degeneration of the thyroid gland, look like very old people. Everyone who has seen the cretins in Savoy, Switzerland, or the Tyrol, must have noticed the aged appearance of these victims, although very often they are quite young. The condition of cretinism, with its pro- found bodily changes, is the result of degeneration of the thyroid gland. On the other hand, it is well known that ' C. R. de la SocUtd de Biologie, 14 November, 1903. ^ Clinica medica, 1905, n. 6. ^ Bulletins de la SocUti royale des scienceS'medicales de Brtixelles, 1905, n. 4, p. 105. MECHANISM OF SENILITY 33 in old people the thyroid and the suprarenals frequently show cystic degeneration. It is quite probable, therefore, that these so-called vascular glands have their share in producing senility. Many facts show that they destroy certain poisons which have entered the body, and it is easy to see that, if they have become functionless, the tissues are threatened with poisoning. It does not follow, how- ever, that their action in producing senility is exclusive, or even preponderating. M. Weinberg, at the Pasteur Insti- tute, made special investigations on this point, and found that the thyroid gland and the suprarenal capsules were almost invariably normal in old animals (cat, dog, horse), although the latter showed unmistakable signs of senility. Similarly in an old man of 80 years, who died from pneu- monia, the thyroid gland was quite normal. It must not be forgotten that the aged very often die from infectious diseases such as pneumonia, tuberculosis, and erysipelas. In these diseases the vascular glands generally, and the thyroid gland in particular, are very often affected, with the result that what is due to infection has been set down as a symptom of old age.^ Although the appearance of patients from whom the thyroid gland has been removed, or in whom it has degene- rated spontaneously, recalls that of old people, it is possible to exaggerate the similarity. In the masterly accounts of such unfortunates, recently compiled by the well-known surgeon Kocher^ there are many points which are char- acteristic, without being typical^ of old people. Oedema of the skin which characterises thyroid patients ' Sarbach, Mittheilungen a. d. Grenzgeb. d. Med. u. Chir., vol. xv. 1906. " Verhandlungen d. Kongr. f. innere Medicin. Wiesbaden, 1906, pp. 59, 98. D 34 THE PROLONGATION OF LIFE is by no means usual in old age. The loss of hair, normal in the patients, is not a character of old age. In myx- edematous women, menstruation is very active; it ceases in old women. The great muscular development of myxedematous patients distinguishes them from old people. Physiological investigation does not support the exist- ence of any strong affinity between old age and affection of the thyroid gland. It is known that removal of the thyroid is followed by cachexia only in young subjects MM. Bourneville and Bricon ^ having shown that the tendency to cachexia after extirpation of the thyroid ceases almost abruptly at the age of thirty. That age may be taken as the limit of youth, of the time when growth is vigorous and the function of the thyroid most active. Cases of cachexia, where the thyroid gland has been removed in old persons from fifty to seventy, are very. rare. Rodents (rats, rabbits) support the removal of the thyroid extremely well, without signs of cachexia, although these are normally short-lived creatures. According^ to Horsley ^ extirpation of the thyroid is not followed by cachexia in birds or rodents and is followed by it only very slowly in rilminants and horses ; it produces the condition invariably but slightly in man and monkeys and extremely seriously in carnivora. If this series be compared with the informa- tion given in the next section of this volume on the relative ages which the animals in question attain, it will be seen that there is no correspondence. In short, whilst I do not deny that the vascular glands may take a share in the causation of senility, in so far as> ^ Archives de Neurologic, 1886. ' Die Function d. Schilddriise, Virchovfs Festschrift, vol. i. 1891, p. 369. MECHANISM OF SENILITY 35 they are destroyers of poisons, I cannot agree with the theory of Dr. Lorand. I think it indubitable that in senescence the most active factor is some alteration in the higher cells of the body, accompanied by a destruction of these by macrophags which gradually usurp the places of the higher elements and replace them by fibrous tissue. Such a process affects the organs of secretion (kidne}'s), the reproductive organs, an( in a modified form the skin, the mucous membranes, and the skeleton. The testes are amongst the organs which resist invasion by macrophags, I have already given an ex- ample (" The Nature of Man," p. g8) of an old man of 94 in whom active spermatozoa were produced. I know of a similar case, the age being 103 years. Such cases are not rare, and not only in old men, but in old animals, the testes continue to Fig. n.— Testis tissue from a dog .iged twenty-two years, be active. Dr. Weinberg and (Krom a preparation made by Dr. I have investigated these Weinberg.) organs in a dog which died at the age nf 12 years after several years of pronounced senility. Many of the organs of the animal exhibited serious invasions by macrophags but the testes were extremely active, the cells being in free proliferation and producing abundant spermatozoa (Fig. 11). In harmony with this condition of the sexual organs, the sexual instincts of the animal remained normal. We have investigated another dog which died at the age of eighteen years. In this case the testes were cancerous and there was no possibility of the production of spermatozoa. None the less, this dog although markedly D 2 36 THE PROLONGATION OF LIFE senile (Fig. 12) still sht)\ved sexual instincts until shortly before it died. It is manifest that the tissues do not invariably degene- rate in old age, nor do all the organs that are modified in old age show destruction '.jy phagocytes and replacement by connective tissue. Organs which produce phagocytes, such as the spleen, the spinal marrow and the lymphatic glands, certainly show traces in old age of fibrous degenera- KiG. 12. — An old 'log, ^':;ed eighteen years. tion but remain sufficiently active to produce macrophags which destroy the higher cellular elements of the body. I have frequentlv noticed cell division in such organs, and as an example .nay gi^'e the case of the bone marrow taken from a man of Si years (Fig. 13). The eye .;; an organ that is modified in _!d age without the action of macrophags. Cataract and the senile arc which appears as a milky ring at the edge of the cornea MECHANISM OF SENILITY 37 are frequent in old age. These modifications are due to impregnation of the parts affected by fatty matter which malves them opaque. This deposition of fat ^ has been attributed to defecti^'e nutrition. In most organs such fatty degeneration is foHowed by phagoc3'tosis, but the cornea and the crystahine lens are exempt from this conse- quence for anatomical reasons. Most organs possess in addition to their higher elements a constant source of macrophags. Such a source of phagocytosis is the neuro- glcea in ner\'Ous tissues, the sarcoplasm in muscular tis- sues; the bones contain osteo- clasts and the liver and the kidneys are readily inyaded by phagocN'tes from the blood. The lens and the cornea have no cells that arc able to become macrophags. Some inferti(">us diseases bring about precocious Senil- (F,.,-,m a preparation made by Dr. ity. A svphilitic child is "a Wcnberg.) miniature old man, with wrinkled face, skin dull and discoloured and flabb\' and hanging in fdlds as if it were too large."'- In such a case the active agent is the microbe of s\-philis which has poisoned the child on the breast oi its mother. It is no mere analogy to suppose that human senescenc(j is the result of a slow but chronic poisoning of the organism. Such pcjisons, if not completeh' destro\-ed or eliminated, weaken the tissues, the functions of which become altered or enfeebled, so thcat, ' Fus^, Dcr Greisenbogen, in V'irchnw's Arclin', 1905, \ol. clxx.xii. p. 407 ; .S. Toufcsco, Siir le crislallin, Paris, 1906. - Edmond Fournier, Stigmates dystrophiqucs de tlicyi!dosypJiiUi, Paris, 189S, p. 4. narrow from the nian ai^cil tittlrt)'- one \'fars. 38 THE PROLONGATION OF LIFE amongst other changes, there is deposition of fatty matter. The phagocytes resist the influence of invading poisons better than any of the other cells of the body and some- times are stimulated by them. The general result of such conditions is that there comes to be a struggle between the higher cells and the phagocytes in which the latter have the advantage. The answer to the question as to whether our senescence can be ameliorated must be approached from several points of view. This course I shall now follow. PART II LONGEVITY IN THE ANIMAL KINGDOM I THEORIES OF LONGEVITV Relation between longevity and size — Longevity and the period of growth — Longevity and the doubling in weight after birth— Longevity and rate of reproduction — Probable relation between longevity and the nature of the food The duration of the life of animals varies within very wide limits. Some, as for instance, the males of certain wheel animalculas (Rotifera) complete their cycle of life from birth to death in 50 or 60 hours, whilst others, like some reptiles, live more than 100 years, and quite possibly may live for two or three centuries. Enquiry has been made for many years as to whether there are laws governing these different durations of life. Even the most casual observation of domesticated animals has shown that, as a general rule, small animals do not live so long as large ones ; mice, guinea pigs, and rabbits for instance, have shorter lives than geese, ducks, and sheep, whilst these again are survived by horses, deer, and camels. Of all the mammals which have lived under the protection of man, the elephant is at once the largest, and the most long-lived. However, it is not difficult to show that there is no absolute relation between size and longevity, since parrots, ravens, and geese live much longer than many mammals, and than some much larger birds. 40 THE PROLONGATION OF LIFE As a general rule it may be said that a large animal takes more time than a small one to reach maturity, and it has been inferred from this that the length of the periods of gestation and of growth were in proportion to the longe- vity. BufFon ^ long ago stated his opinion that the " total duration of life bore some definite relation to the length of the period of growth." Therefore, as the period of growth is, so to say, inherent in the species, longevity would have to be regarded as a very stable phenomenon. Just as any species has acquired a fixed and practically invariable size, so it would have acquired a definite longe- vity. Buffon, therefore, thought that the duration of life did not depend on habits or mode of life, or on the nature of food, that, in fact, nothing could change its rigid laws, ejjcept an excess of nourishment. Taking as his standard the total period of development of the body, Buffon came to the conclusion that the dura- tion of life is six or seven times that of the period of growth. Man, for instance, he said, who takes 14 years to grow, can live 6 or 7 times that period, that is to say, 90 or 100 years. The horse, which reaches its full size in 4 years, can live 6 or 7 times that length of time, that is to say from 25 to 30 years. The stag takes 5 or disinfect the contents of the large intestine — Prolonged mastication as a means of preventing intestinal putrefaction The general measures of hygiene directed against infec- tious diseases play a part in prolonging the lives of old people, but, in addition to the microbes which invade the body from outside, there is a rich source of harm in the microbes which inhabit the body. The most important of these belong to the intestinal flora, which is abundant and varied. The intestinal microbes are most numerous in the large intestine. This organ, which is useful to mammals the food of which consists of rough bulky vegetable matter, and which require a large reservoir for the waste of the process of digestion, is certainly useless in the case of man.i In the " Nature of Man " I have dealt with this ' According to a recent publication of M. Ellenberger {Archiv. f. Anatomic u. Physiologic, Physiologischc Abtheilung, 1906, p. 139), the caeca of the horse, pig and rabbit, play an active part in the digestion of vegetable matter, which is rich in cellulose. At the end of his treatise, Ellenberger insists that the vermiform appendix of the caecum Js not a rudimentary organ. The reason why the appendix can be 152 THE PROLONGATION OF LIFE question at length, as it was an important example of what I regard as the disharmonies of the human constitu- tion. A case upon which I have always laid great stress is that of a woman who lived for thirty-seven years, although her large intestine was atrophied and inactive, as this seems to be a remarkable proof of the uselessness of ■ the organ in the human body. The small size or complete absence of the large intestine in many vertebrates confirms my conclusion. None the less, some of my critics think that my argument is incomplete. To strengthen it, I may call their attention to a medical observation which is as valuable as if it had been an experiment. It relates to a woman, sixty-two years old, a patient of Prof. Kocher at Berne. She had been suffering from a strangulated hernia associated with gangrene of part of the intestine, and had to be operated upon suddenly. The gangrenous portion of the ileum having been re- moved, the healthy part was implanted in the skin so as to form an artificial aperture through which waste matter from the food passed lo the exterior without traversing the large intestine. Although the patient was old and seriously ill, the operation, performed by M. Tavel, was quite suc- cessful. Six months later, in a new operation, the small intestine was rejoined to the large intestine so that the faeces were again able to pass to the exterior by the natural channel. In this case, then, the large intestine was thrown out of use for half a year, not only without injury to the general health, but with the result that the patient was corn- removed in the case of man without disturbance to the functions of the body, is that this work can be performed by the Peyer's patches of the intestine. The existence of the appendix is not necessary to the normal processes of the body, and is a real danger to health and sometimes to life. Comparative study of the casca in birds shows that these organs are in process of degeneration. PUTREFACTION SHORTENS LIFE 153 pletely cured and gained in weight. MM. Macfadyen, Nenclii, and Mde. Sieber ' studied the digestive processes in the small intestine and the nutritive metabolism, and determined that these were active and healthy, the absence of intestinal putrefaction, that evil of the constitution, being specially favourable. In six months of non-action, the part played by an organ Fig. 19. — Diagram of the lower bowel in a female patient. A.C.N., Artificial anus : A.S., Insertion of the ileum to the colon. ■ • (After M. Mauclaire.) can be satisfactorily estimated. M. Mauclaire,^ however, has put on record a case the history of which was longer. In 1902 he operated on a young woman and produced an artificial anus, there being no escape of faecal matter by the ordinary channel. Ten months later M. Mauclaire operated a second time and shut off a portion of the intes- tine. He left the artificial anus, but cut across ' Archiv.fiir experimentelle Pathologie, vol. xxviii, p. 311. ' Sixiime Congrh de Chirurgie, Paris, 1903, p. 86. 154 THE PROLONGATION OF LIFE the lower end of the small intestine and inserted it near the iliac end of the descending colon (Fig. 19). For several days after the operation the faeces were passed by the normal aperture, as the small intes- tine now communicated directly with the large intestine, near the rectum. This condition, however, did not persist, for the faecal matter began to flow back through the ex- cluded portion of the large intestine, so reaching the artifi- Fio. 20. — Diagram of the lower bowel, after a third operation, on the case in Fig. 19. (After M. Mauclaire.) cial anus, and causing inconvenience. Giving up the hope that this would cease, M. Mauclaire performed a third opeiation twenty qionths later. He cut across the large intestine near the point where the small intestine had been artificially led into it (Fig. 20), so dividing the digestive tube into two parts, one of which remained in communica- tion with the natural anus, whilst the other, consisting of PUTREFACTION SHORTENS LIFE 155 nearly the whole of the large intestine, communicated with the exterior by the artificial anus. In the new state of affairs, the food refuse passed directly into the terminal portion of the large intestine, and thence, by way of the rectum, to the exterior through the normal anus without being able to pass up the large intestine towards the arti- ficial anus. In this last operation about a yard of the small intestine and the greater part of the large intestine, the caecum, and ascending, transverse and descending colons were removed from activity. By the kindness of M. Mauclaire, I have been able to watch his patient during the last four years. I satisfied myself that after the supposed exclusion of the large intes- tine, food dejecta ascended the colon and emerged by the artificial anus. There was such an accumulation of waste in the large intestine that fragments did not emerge until three weeks after the meal of which they had formed part. It was only after the finaj operation, that in which the large intestine was separated, that the dejecta escaped only by the natural anus, whilst a little mucus containing microbes was passed through the artificial aperture. Even three years after the operation, mucus continued to escape by the latter aperture, it being shown thus that after the large intestine had ceased to be a channel for the faeces, its walls continued to secrete although otherwise it had lost its function com- pletely. Nevertheless the condition of this patient improved and she lived perfectly well without a functional large in- testine. She takes food well but has to go to stool three or four times a day and has a tendency to diarrhoea. The excreta are smooth and often nearly liquid, especially after fruit has been eaten. The case I have been describing, and which I am still keeping under observation, demonstrates once more the use- lessness of the human large intestine ; it should convert the 156 THE PROLONGATION OF LIFE most sceptical critic. But it also shows that the suppres- sion of nearly the entire large intestine for several years does not completely get rid of the intestinal flora. Even without this evidence, however, I do not suggest that re- moval of the large intestine can be thought of as a means to prevent the pernicious efifect of the intestinal flora. Is it possible, without operative interference, to take direct action against the intestinal flora by the use of anti- septics? Consideration of this is already ancient history. When the theory that the intestine was a source of auto- intoxication was propounded, M. Bouchard* made the at- tempt to cure such cases by disinfecting the digestive tube with |8-naphthol. He found, however, that that anti- septic, like many others, not only did not completely dis- infect the intestine but sometimes had a harmful effect on the body. M. Stern 2 has shown, in an elaborate memoir, that such antiseptics as calomel, salol, /8-naphthol, naphthaline, and camphor, when administered in quantities compatible with health, do not disinfect the digestive tube at all. More recently M. Strasburger ^ has shown that when naphthaline has been given in quantities sufificient to impart its odour to the faeces, the intestinal microbes, so far from being dimin- ished, are even increased in numbers. On the other hand, after meals consisting of milk to which there has been added an antiseptic in the proportion of a quarter of a gram to the litre, the intestinal microbes are really reduced in number. Strasburger obtained his best results with tano- col. Two persons who used, according to this method, three to six grams of tanacol per day, displayed a notable reduction in quantity of the intestinal flora. Strasburger's conclusion was that " the attempt to destroy ' Leqons sur les auto-intoxications, Paris, 1886. Zeitsehrift fiir Hygiene, 1892, vol. xii, p. 88." ' Zeitschrift$fur kUnische Mediiinx 1903, vol. xlyiii, p. 491. PUTREFACTION SHORTENS LIFE 157 the intestinal microbes by the use of chemical agents has little chance of success." It cannot be denied that under special circumstances it is possible to decrease the number of microbes, especially in the small intestine. But this result is small and may be followed by the contrary effect, for the natural means of defence of the intestine against microbes are weakened, and the intestine itself may be harmed more than the microbes. Strasburger, moreover, is no convinced advocate of the use of purgatives. The diminution of the sulpho-con jugate ethers in the urine, which certainly may follow the use of purgatives, does not necessarily indicate reduced putrefaction in the intestine, b|Ut may point only to a less- ened absorption of the bacterial products. Such an inter- pretation is supported by an observed fact; in the case of a dog belonging to Strasburger, which had a fistula of the small intestine, the diarrhoea induced by calomel was ac- companied by an indubitable increase in the total quantity of intestinal microbes. Strasburger thinks that the most favourable results can be obtained by aiding the intestine in the discharge of its normal function. If it can be brought to digest the food more completely, there is the less pabulum left for the microbes. A similar result can be reached by lowering the amount of food taken, and to this course the beneficial effects of starvation in acute diseases of the intestine may be attributed. The general conclusion, reached after many experiments on the disinfection of the intestine, is unfavourable. Very little is to be expected from the method. None the less I cannot regard the matter as definitely settled. Cohendy has investigated the effect on the intestinal flora of thymol which was administered in several cases with the object 158 THE PROLONGATION OF LIFE of destroying parasites. From nine to twelve grammes of thymol were administered to each patient in the space of three days, and there was a notable antiseptic effect, Cohendy believing that the quantity of microbes had been reduced to a thirteenth. Such facts prove only that the antiseptic treatment is available up to a certain point. To attain the results, how- ever, such large quantities must be used that the treatment can be applied only in special cases and at long intervals. More use can be made of simple purgatives which do not kill the microbes but eliminate them by the normal channel. It has been urged repeatedly that calomel, which is often used as a purgative, acts also as an intestinal antiseptic ; but it is probable that its influence in reducing the intes- tinal flora is merely mechanical. It has been shown that calomel, like some other purgatives, lessens intestinal putrefaction, the evidence being the decrease in the sulpho-conjugate ethers in the urine. But although the diarrhoea induced by purgatives generally has such a result, spontaneous diarrhoeas such as those of typhoid fever and of intestinal tuberculosis are associated with increased putref action. 1 It is clear, however these matters may be settled, that regular activity of the bowels, increased by the occasional use of purgatives, must diminish the formation of intestinal poisons, and therefore also the damage done by these to the higher elements of the body. When I asked the relatives of Mde. Robineau if they could tell me of any special circumstance which in their opinion had contributed to the extreme duration of the life • There is a summary of this question in Gerhardt's work on intes- tinal putrefaction, in Ergebnisse der Physiologic, 3rd year, section i, Wiesbaden, 1904, pp. 107-154. PUTREFACTION SHORTENS LIFE 159 of this old lady, they replied as follows : — " We are con- vinced that a slight bodily derangement, present for the last fifty years, has tended to prolong the life of the old lady. It cannot be said that she has suffered from diarrhoea, but she has been often subject to frequent calls of nature." It was most remarkable that the old lady showed no traces of sclerosis of the arteries. I may mention the strongly con- trasting caee of one of my old colleagues to whom a natural desire to empty the bowels came only once a week. A more frequent call was a sign of illness in his case. Now sclerosis of the arteries appeared in so marked a form that he died from it before he had reached the age of fifty years. This may be added to the list of facts which point to a close association between sclerosis of the arteries and the functions of the digestive tube.. Recently, at the suggestion of Mr. Fletcher,* the advan- tage of eating extremely slowly has been recognised, the object being to prepare for the utilisation of the food mate- rials, and to prevent intestinal putrefaction. Certainly the habit of eating quickly favours the multiplication of microbes round about the lumps of food which have been swallowed without sufficient mastication. It is quite harm- ful, however, to chew the food too long, and to swallow it only after it has been kept in the mouth for a considerable time. Too complete a use of the food material causes want of tone in the intestinal wall, from which as much harm may come as from imperfect mastication. In America, where Fletcher's theory took its origin, there has already been described under the name of " Bradyfagy" a disease arising from the habit of eating too slowly. Dr. Einhorn,' ' The A B C of our Nutrition, New York, 1903 ; Dr. Regnault, Nov. I, " L'art de manger," La Revue, 1906, p. 92. * Zeitschr.f.diatetischeu.physikal, Therapie,t. viii, 1904, 190J. i6o THE PROLONGATION OF LIFE a well-known specialist in the diseases of the digestive sys- tem, has found that several cases of this disease Xvere rapidly cured when the patients made up their minds to eat more quickly again. Comparative physiology supplies us with arguments against too prolonged mastication. Rumi- nants, which carry out to the fullest extent Mr. Fletcher's plan, are notable for extreme intestinal putrefaction and for the short duration of their lives. On the other hand, birds and reptiles, which have a very poor mechanism for break- ing up food, enjoy much longer lives. Prolonged mastication, then, cannot be recommended as a preventative of intestinal putrefaction any more than the surgical removal of the large intestine or the disinfection of the digestive tube. The field lies open for other means which may probably solve the problem more completely and more pi-actically. LACTIC ACID AS INHIBITING INTESTINAL PUTREFACTION The development of the intestinal flora in man — Harmless- ness of sterilised food — Means of preventing the putrefaction of food- — Lactic fermentation and its anti-putrescent action — Experiments on man and mice — Longevity in races which use soured milk — Comparative . study of different soured milks — Properties of the Bulgarian Bacillus — Means of pre- venting intestinal putrefaction with the help of microbes At birth the human intestine is full, but contains no microbes. Microbes very soon appear in it, because the meconium, the contents of the intestines of new-born chil- dren, composed of bile and cast-off intestinal mucus cells, is an excellent culture medium for them. In the first hours after birth, microbes begin to reach the intestine. In the first day, before the child has taken any food whatever, there is to be found in the meconium a varied flora, com- posed of several species of microbes. Under the influence of the mother's milk this flora is reduced and comes to be composed almost entirely of a special microbe described by M. Tissier and called by him Bacillus bifidus. The food, therefore, has an influence on the microbes of the intestine. If the child be fed with cow's milk, the flora is richer in species than in the case of a child suckled by its mother. Later on, also, the flora varies with the food, as has been proved by MM. Macfadyen, Nencki, and Mde. M 1 62 THE PROLONGATION OF LIFE Sieber in the case of a woman with an intestinal fistula. The dependence of the intestinal microbes on the food makes it possible to adopt measures to modify the flora in our bodies and to replace the harmful microbes by useful microbes. Unfortunately, our actual knowledge of the in- testinal flora is still very imperfect because of the impos- sibility of finding artificial media in which it could be grown. Notwithstanding this difficulty, however, a rational solution of the problem must be sought. Man, even in the savage condition, prepares his food be- fore eating it. He submits much of it to the action of fire, thus notably lessening the number of microbes. Microbes enter the digestive tube in vast numbers with raw food, and in order to lessen the number of species in the intestines, it is important to eat only cooked food and to drink only liquids that have been previously boiled. In that way, although we cannot destroy all the microbes in the food, because some of them can withstand the tempera- ture of the boiling point of water, we. can kill the great majority of them. It has sometimes been supposed that cooked or com- pletely sterilised food (that is to say food that has been subjected to a temperature of from 248°-284° Fahr.) is harmful to the organism and that much of it is not well digested. From this point of view protests have been made against the feeding of infants with sterilised milk or even with boiled milk. Although in certain cases steril- ised milk is not well supported by infants, it cannot be doubted but that boiled milk and cooked food are generally successful. The large number of children brought up suc- cessfully on boiled cow's milk and the health of travellers in arctic regions are ample proof of this. I have been told by M. Charcot that in his voyage to the antarctic LACTIC ACID AND PUTREFACTION 163 regions, he and his companions lived entirely on sterilised food, or on cooked food such as the flesh of seals and penguins. As they had no green food nor fresh fruit, the only raw food that they ate was a little cheese. Living under these conditions, all the members of the expedition enjoyed good health, and there was no case of digestive disturbance in the whole period of sixteen months. It is obvious that abstaining from raw food, and so reducing largely the entrance of new microbes, by no means causes the disappearance of the intestinal flora already existing. We must reckon with that and with the evil that it does by weakening the higher cells of the tissues. As the part of the flora that does most damage consists of microbes which cause putrefaction of the con- tents of the intestine and harmful fermentations, particu- larly butyric fermentation, it is against these that our efforts must be directed. Long before the science of bacteriology was in exist- ence, men had turned their attention to methods of pre- venting putrefaction. Food, especially if it be kept in a warm place or in a moist atmosphere, soon begins to putrefy and to become unpleasant to the taste and danger- ous to the health. Everyone has known cases of poison- ing from putrid flesh or other food material. Fok,^ the explorer of Central Africa, has related that once, when they were starving, he and his men came on the putrefying body of an elephant. The negroes rushed to lay hold of the carrion, but Foa tried to dissuade them, explaining that to eat flesh in such a state was as bad as taking poison. All did not listen to him, and three negroes, who had taken pieces of the body, swallowed them before they had been properly cooked. All three died in a few days, ■ £>u Cap au lac Nyassa, Paris, 1897, pp. 291-294. M 2 164 THE PROLONGATION OF LIFE with the neck and throat swollen, the tongue almost para-f lysed, and the abdomen inflated. In another case, sausages made of putrid horse flesh caused an epidemic at Rohrsdorf, in Prussia, in 1885.^ About forty people fell ill after having eaten the sausages, which, according to witnesses, were green in colour, smelt badly, and had a revolting appearance. One person died, whilst the others recovered after cholera-like symptoms. It is true that all putrefying food does not produce the same effect. MM. Tissier and Martelly^ found no diges- tive trouble after having eaten food that was quite putrid. Everyone knows that the Chinese prepare a dish particu- larly pleasant to gourmets by allowing eggs to putrefy. Some decaying cheeses are harmful to the health, but others can be eaten with impunity. The reason of this is that whilst putrefying food may contain microbes and dangerous toxins, it does not contain them in all cases. On the other hand, we must take into account the different susceptibilities of people to the harmful action of microbes and their products. Some can swallow without any evil result a quantity of microbes which in the case of other individuals would produce a fatal attack of cholera. Every- thing depends upon the resistance offered to the microbes by the invaded organism. Experiments on animals fed on putrefying food have also given varied results. Some animals eat it without any harm resulting, others have attacks of vomiting and show such a repugnance that it is impossible to continue the experiment. Not only flesh and other animal substances, but vege- tables can undergo putrefaction and fermentation (butyric) ' Gaflfky and Paak, in Arbeiten d. k. Gesundheitsamtes, vol. vi, 1890. * Annales detlnstitut Pasteur, 1903. LACTIC ACID AND PUTREFACTION 165 which make it dangerous to eat them. Many accidents have occurred in man as the result of deteriorated pre- served fruit. Vegetables, preserved in silos to feed cattle, sometimes go wrong. "If, for instance, rainy days come after sunny days, so that the uncovered fodder is wetted again, the resulting ensilage is poor and has an extremely unpleasant butyric odour, so that the animals turn from it." Sometimes the fodder grows black in the silo, and acquires a special smell. "The animals will take it only in the absence of other food ; their excreta become black, and if they are kept on such a diet for a time they waste in a marked manner."^ In popular practice, the value of acids for preserving animal and vegetable food and for preventing putrefaction has long been recognised. Meats of all kinds, fish and vegetables have been "marinated" with vinegar, as the acetic acid in that substance, the product of bacteria, wards off putrefaction. If the materials which it is desired to preserve give off acids themselves, the addition of vinegar may be unnecessary. For this reason some animal products such as milk, or vegetables rich in sugar become acid spontaneously and so can be preserved. Soured milk can be made into many kinds of cheese, and these last for longer or shorter times. Many vegetables can undergo a natural process of souring, when they "keep" without difficulty. Thus cabbage becomes " sauer-kraut " and beetroot and cucumbers pass into an acid state. In many countries, as for instance in Russia, the use of acidi- fied vegetables is of great importance in the food-supply of the populace. Fresh fruit and vegetables cannot be obtained in the long winters, during which the people con- * Cormouls-Houl^s, Vingt-sept armies ^agriculture pratique, Paris, 1899, pp. 57-58. 1 66 THE PROLONGATION OF LIFE sume large quantities of cucumbers, melons, apples, and other fruits which have undergone an acid fermentation in which lactic acid is the chief product. During summer, milk, which acidifies readily, is the chief source of acid materials for consumption. The chief beverage is "kwass," of which black bread is the main ingredient, and this passes through not only an alcoholic fermentation, but an acidifying change in which lactic acid is the most important product. Rye bread, the chief food of the populace, is also a product of fermentations amongst which the- lactic acid fermentation is most important, but in other kinds of bread also there is a fermentation in which some of the sugar is transformed to lactic acid. Soured milk, because of the lactic acid in it, can impede the putrefaction of meat. In certain countries, accord- ingly, meat is preserved in acid skimmed milk with the result that putrefaction is prevented. Lactic acid fermenta- tion is equally important in the food supply of cattle. It is the chief agent that, in the process of preserving vege- tation in silos, hinders putrefaction. Finally, the same fermentation serves in distilleries to preserve the must from which alcohol is prepared. This short review is in itself enough to show the great importance of lactic fermentation as a means of stopping putrefaction and butyric fermentation, both of which hinder the preservation of organic substances and are capable of exciting disturbances in the organism. As lactic fermentation serves so well to arrest putrefac- tion in general, why should it not be used for the same purpose wiihin the digestive tube ? It is a matter of common knowledge that putrefaction and butyric fermentation are arrested in the presence of LACTIC ACID AND PUTREFACTION 167 sugar. Whereas meat preserved without special care soon putrefies, milk in exactly the same conditions does not putrefy, but becomes sour, the reason being that meat is poor in sugar whereas milk contains a good deal of it. However, the scientific explanation of this fundamental fact is difficult. It has been shown conclusively that sugar itself cannot prevent putrefaction. Milk, for instance, howr ever rich in sugar it may be, readily putrefies in certain conditions. Sugar preserves organic matter from putre- faction only because it can readily undergo lactic fermentar tion, and this fermentation is the work of the microbes described fifty years ago by Pasteur. That great dis- covery proved the part played by microbes in fermenta- tion and founded bacteriology, a science equally rich in theory and in practice. I need not pause to develop the theme that the anti- putrescent action of the lactic fermentation depends on the production of lactic acid by microbes, because I have explained the matter at length in the tenth chapter of the "Nature of Man." If the lactic acid be neutralised, the organic matter soon putrefies, notwithstanding the pre- sence of the lactic microbes. The most important point is as to whether lactic fermentation really arrests intestinal putrefaction. Several sets of observations have been made upon this matter. Dr. Herter,^ of New York, injected directly into the small intestine of a number of dogs quantities of different microbes. To test the action of these on intestinal putrefaction, he investigated the sulpho- conjugate ethers in the urine, as he believed, in accord- ance with current and well justified opinion, that these substances are the best proofs of the existence of putrefaction. He found that whilst the introduction of * British Medical Journal, 1897, Dec. 2Sth, p. 1898. 1 68 THE PROLONGATION OF LIFE quantities of Bacillus colt or Bacillus proteus increased the intestinal putrefaction, lactic bacilli notably lessened it. Herter found a notable diminution of sulpho-conjugate ethers in the urine of dogs which had been treated with the lactic microbes. The experiments which Dr. M. Cohendy^ performed upon himself during a period of nearly six months are still more interesting. When Dr. Cphendy had proved that much intestinal putrefaction occurred during a period of 25 days, in which he lived on an ordinary mixed diet, he began to take pure cultures of lactic bacillus, taken from yahourth. In a period of 74 days, he took quarttities varying from 280 to 350 grams of the culture. Analysis of the urine during the progress of the experi- ment showed that intestinal putrefaction had notably de- creased whilst the lactic bacilli were being taken, and that the diminution persisted seven weeks after the taking of the bacilli ceased. Dr. Cohendy gives it as the direct result of his experiment that the introduction of lactic ferment into the intestine definitely arrests putrefac- tion. He obtained this result on a diet consisting of 400 grams of soup, 150 of meat, 700 of grain-food, 400 of green vegetables, 300 of fruits and dessert and a litre of water. He came to the conclusion that the elimination of meat from the diet was unnecessary, as the particular kind of lactic ferment he employed was extremely active in in- hibiting the proteolytic ferments. Later experiments made by Dr. Cohendy showed that the lactic bacillus became so acclimatised in the human intestine that it was to be found there several weeks after it had been swallowed. ' Comptes rendus de la Soc. de Biologic, 1906, March 17th. LACTIC ACID AND PUTREFACTION 169 Dr. Pochon, assistant to Professor Combe ^ at Lausanne, has repeated on himself the experiments of Cohendy, He took for several weeks mill: curdled with pure cultures of lactic acid microbes and obtained " results that were quite definite as to intestinal putrefaction." Analysis of his urine showed that there was a marked diminution of indol and phenol, substances which are certain indexes of in- testinal putrefaction. In addition to such observations on lactic bacilli there is a good deal of knowledge as to the effect of lactic acid taken in bulk. The result of the various observations* shows that the acid lessens intestinal putrefaction and lowers the quantity of sulpho-conjugate ethers in the urine. This fact explains why favourable results follow the use of lactic acid in many intestinal diseases such as infantile diarrhoea, tuberculous enteritis and even Asiatic cholera. The addition of this remedy to practical thera- peutics is due chiefly to Professor Hayem. It is employed not only in the treatment of diseases of the digestive system (dyspepsia, enteritis and colitis), but is indicated also in diabetes and is used locally in tuberculous ulcera- tions of the larynx. As quantities up to twelve grams can be given by the mouth daily, it is plain that the system is tolerant of this acid. It is either oxidised in the tissues or excreted with the urine. In the case of a diabetic woman who had taken 80 grams of lactic acid in four days, Nencki and Sieber* found no traces of it ' Dr. Combe, L'auto intoxication intestinale, Paris, 1906. This valuable work contains much useful information on the subject. ^ Grundzach, Zeitschrift fUr klinische Medezin, 1 893, p. 70 ; Schmiti, Zeitschrift fiir physiologische Chemie, 1894, vol. xix, p. 401; Singer, Therapeuliiche Monatshefte, 1 901, p. 441. * Journal fiir praktische Chemie, 1882, vol. xxvi, p. 43. 1 70 THE PROLONGATION OF LIFE in the urine. On the other hand, Stadelmann^ found a notable quantity of the acid in another diabetic patient who had been taking over four grams daily, f. The general interpretation of the benefits gained from the use of lactic acid ferments is that they depend solely on the action of the lactic acid which they produce in preventing the multiplication of the microbes which cause putrefaction. Recent investigations made by Dr. B^lon- owsky, at the Pasteur Institute, show that a lactic ferment isolated from yahourth and described as the Bulgarian bacillus owes its antiseptic powers not only to lactic acid but to another substance which it secretes. Dr. B^lon- owsky has studied the effects of this bacillus upon mice, by adding to their previously sterilised food quantities of this lactic microbe. As control experiments he fed other mice on food to which lactic acid had been added in quantities corresponding to the quantity produced by the Bulgarian bacillus, or which had been mixed with other kinds of bacilli. Another set of mice were given normal food without the addition of either microbes or lactic acid. Out of these groups of mice, those which had been given the Bulgarian bacillus thrived best and had most progeny. Their droppings showed fewest microbes, particularly microbes of putrefaction. The next stage in Dr. Belonowsky's experiments was to feed mice not with living quantities of the Bulgarian bacillus, but with cultures which had been sterilised by heat (i2o°-i40° Fahr.). These mice lived as well as those to which living cultures had been supplied, and notably better than those supplied with pure lactic acid. It is evident therefore that there is some other product of this ' Atchiv. fiir experimentelle Pathologie, 1883, vol. xvii, p. 442. LACTIC ACID AND PUTREFACTION 171 bacillus which favours life by preventing intestinal putrefaction. Dr. B^lonowsky showed, moreover, that the Bulgarian bacillus cures a special intestinal disease known as mouse typhus. The experiments which I have described show that in- testinal putrefaction is to be combated not by lactic acid itself, but by the introduction into the organism of cultures of the lactic bacilli. The latter become acclimatised in the human digestive tube as they find there the sugary material required for their subsistence, and by producing disinfecting bodies benefit the organism which supports them. From time immemorial human beings have absorbed quantities of lactic microbes by consuming in the uncooked condition substances such as soured milk, kephir, sauer- kraut, or salted cucumbers which have undergone lactic fermentation. By these means they have unknowingly lessened the evil consequences of intestinal putrefaction. In the Bible soured milk is frequently spoken of. When Abraham entertained the three angels he set before them soured milk and sweet milk and the calf which he had dressed (Genesis xviii. 8). In his fifth book, Moses enumerates amongst the food which Jehovah had given his people to eat " Soured milk of kine and goat's milk, with fat of lambs and rams of the breed of Bashan, and goats with the fat of kidneys" (Deut. xxxii. 14).! A food known as " Leben raib," which is a soured milk, prepared from the milk of buffaloes, kine or goats, has ' In the English authorised version as in the translation of Oster- wald the word "butter" is used in place of "soured milk." Professor Metchnikoff follows the translation given by Ebstein in his work on the Medicine of the Old Testament. 172 THE PROLONGATION OF LIFE been used in Egypt from the remotest antiquity. A similar preparation known as "yahourth" is familiar to the populations of the Balkan Peninsula. The natives of Algiers make a kind of " leben " not identical with the Egyptian form. Soured milk is consumed in great quantities in Russia in two forms, " prostokwacha, " which is raw milk spon- taneously coagulated and soured, and "varenetz," which is boiled milk soured with a yeast. The chief food of many natives of tropical Africa con- sists of soured milk. The staple diet of the Mpeseni is " a curdled milk, almost solidified." " Meat is eaten only on ceremonial occasions." According to Fok, a tribe of the Nyassa-Tanganyika plateau, like the Zulus, take milk only in the form of a raw cheese mixed with salt and pepper. Dr. Lima of Mossamedes, in West Africa, has told me that the natives of many regions south of Angola live almost entirely on milk. They employ the cream as an ointment for the skin, whilst the milk, soured and curdled, is their staple food. M. Nogueira reported the same cir- cumstances nearly fifty years ago after his journey in the province of Angola. Jiist as cheeses vary in different countries, so curdled milk varies slightly according to the nature of the flora of microbes. Taking all the soured milks that are pro- duced by natural processes, it may be said that the greater number of them contain not only microbes that produce lactic acid, but also yeasts that cause alcoholic fermenta- tions. Kephir, which is prepared from the milk of kine, and koumiss, which is a product of mares' milk, are notably alcoholic. Koumiss is the well-known national beverage of the Kirghises, Tartars and Kulmucks, nomads LACTIC ACID AND PUTREFACTION 173 of Asiatic Russia who are famous horse breeders, whilst kephir is the native drink of the mountaineers of the Caucasus, the Ossetes, and some other tribes. It has been supposed that the chief merit of kephir was that it was more easy to digest than milk, as some of its casein is dissolved in the process of fermentation. Kephir, in fact, was supposed to be partly digested milk. This view has not been confirmed. Professor Hayem thinks that the good effects of kephir are due to the presence of lactic acid which replaces the acid of the stomach and has an antiseptic effect. The experiments of M. Rovighi, which I spoke of in The Nature of Man, have confirmed the latter fact, which now may be taken as certain. The action of kephir in preventing intestinal putrefaction de- pends on the lactic acid bacilli which it contains. Kephir, although in some cases certainly beneficial, cannot be recommended for the prolonged use necessary if intestinal putrefaction is to be overcome. It is produced by combined lactic and alcoholic fermentations, and as it contains up to one per cent, of alcohol, its use as a food for years would involve the absorption of considerable quantities of alcohol. The yeasts which produce it can be acclimatised in the human digestive tract, in which, how- ever, they are harmful, as they are favourable to the germs of infectious diseases such as the bacillus of typhoid fever, and the vibrio of Asiatic cholera. Kephir has also the disadvantage that its flora varies considerably and is not well known. There has been little success in producing it by pure cultures as would be necessary were it to be brought into general use. When it is prepared from a dried remnant there is the risk of stray microbes being included, and these may bring about pernicious fermentations. Professor Hayem prohibits its 174 THE PROLONGATION OF LIFE use in the case of persons in whom food is retained for long in the stomach. " When it is retained in the stomach, kephir goes on fermenting, and there are developed in the contents butyric and acetic acids which aggravate the diges- tive disturbances." ^ As it is the lactic and not the alcoholic fermentation on which the valuable properties of kephir depend, it is correct to replace it by soured milk that contains either no alcohol or merely the smallest traces of it. The fact that so many races make soured milk and use it copiously is an excellent testimony to its usefulness. M. Nogueira has written to me to say how much he was astonished, on revisiting after a long period of absence the district of Mossamedes, to find the natives so well pre- served and displaying so few traces of senility. Dr. Lima has stated that amongst the natives of the region south of Angola "many individuals of extraordinary longevity are to be found.'" Although they are thin and withered, these old people are very active and can make long journeys. Mr. Wales, a lawyer at Binghampton, U.S.A., has been so good as to make me acquainted with some extremely interesting facts taken from a work by James Riley which is now a bibliographical rarity.* In the narrative of a ship- wreck of the vessel on which he made a voyage in 1815, James Riley states that the wandering Arabs of the desert live almost wholly on the milk of camels, fresh or soured. * Presse tnidicale, 1904, p. 619. ' " An authentic narrative of the loss of the American brig Commerce wrecked on the western coast of Africa in the month of August, 1815, with an account of the sufferings of the surviving officers and crew, who were enslaved by the wandering Arabs on the African desert 01 Zaharah ; and observations historical, geographical, etc." by James Riley. Hartford, S. Andrus and Son, 1854. LACTIC ACID AND PUTREFACTION 175 On this diet they enjoy excellent health, display great vigour and reach advanced ages. Riley estimated that some of the old men must have lived for two to three hundred years. No doubt these figures are much too high, but it is probable that the Arabs Riley encountered lived really unusually long. Mr. Wales has examined Riley's work critically, and is of the opinion that that author was a well-informed, sagacious and conscientious observer. M. Grigoroff, a Bulgarian student at Geneva, has been surprised by the number of centenarians to be found in Bulgaria, a region in which yahourth, a soured milk, is the stable food. Some of the centenarians, described by M. Chemin in his memoir, lived chiefly on a milk diet. Marie Prion, for example^ who died in the Haute-Garonne in 1838 at the age of 158 years, had lived for the last ten years of her life entirely on cheese and goat's milk (op. cit. p. 100). Ambroise Jantet, a labourer of Verdun, who died in 1751 at the age of in years, " ate nothing but unleav- ened bread and drank nothing but skimmed milk " (p. 133). Nicole Marc, who died aged 1 10 years, at the chateau of Colemberg (Pas-de-Calais), a hunch-back and cripple, " lived only on bread and milk-food. It was only towards the end of her' life and after much persuasion that she took a little wine " (Chemin, p. 139). I owe to the kindness of M. Simine, an engineer in the Caucasus, the following communication, taken from the newspaper Tiflissky Listok, Oct. 8th, 1904. " In the village of Sba, in the district of Gori, there is an old Ossete woman, Thense Abalva, whose age is supposed to be about 180 years (?). This woman is still quite capable and looks after her household duties and sews. Although she is bent, she walks firmly enough. Thense has never 176 . THE PROLONGATION OF LIFE taken alcoholic liquors. She rises early in the morning, and her chief food is barley bread and butter milk, taken after the churning of the cream. Butter milk is a liquid containing very many lactic microbes. Mrs. Jenny Read, an American, has written to me that her father, eighty-four years old, " owes his health to the curdled milk which he has taken for the last 40 years." Curdled milk and the other products of milk to which I have referred are the work of the lactic microbes which produce lactic acid at the expense of milk sugar. As many different kinds of soured milk have been consumed on a vast scale and have proved to be useful, it might be supposed that any of them is suitable for regular con- sumption with the object of preventing intestinal putrefac- tion. From the point of view of flavour I find that soured milk, prepared from raw milk, is much the more agree- able. However, when a food is to be selected for con- sumption during a long period of time, we must keep hygiene strictly in view. It is certain, therefore, that the Russian " prostokwacha," as well as any other soured raw milk, must be rejected. Raw milk contains a large assortment of microbes, and frequently some of these are harmful. The bacillus of bovine tuberculosis, as well as other pernicious microbes, may be foiind in it. Accord- ing to the investigations of Heim ^ the vibrios of Asiatic cholera, when placed in raw milk, survive even when the milk has become quite soured. In similar conditions the bacillus of typhoid fever remains alive for 35 days and dies only after it has been kept for 48 days in completely soured milk. ' Arbeiten a. d. k. Gesundheitsamte, 1889, vol. v, pp. 297-304. LACTIC ACID AND PUTREFACTION 177 As raw milk nearly always contains traces of fecal matter from the cow, it sometimes happens that pernicious microbes are introduced from that source^ and remain alive notwithstanding the acid coagulation of the milk. The lactic microbes certainly prevent the multiplication of other microbes, as, for instance, those of putrefaction, but are incapable of destroying them. Moreover, raw milk often contains fungi (yeasts, torulas, and oidia) the presence of which is favourable to the development of such pernicious microbes as the cholera vibrio and the bacillus of typhoid fever. Prolonged consumption of raw milk increases the risk of introducing dangerous microbes into the organism, and this possibility drives me to recommend soured milk pre- pared after heating. Theoretically, it would be best to sterilise the milk completely so that all the contained microbes would be destroyed. This, however, requires heating the milk to a temperature of from 226° to 248° Fahr., by which it acquires an unpleasant flavour. On the other hand, the pasteurising of milk at a temperature of about 140° Fahr. is not sufficient to get rid entirely of the bacilli of tuberculosis and the spores of the butyric bacilli. We have, therefore, to fall back on a middle course, and be content with boiling the milk for several minutes. By so doing we certainly kill the tubercle bacilli and the spores of some of the butyric bacilli,' there being left only some butyric spores and the spores of Bacillus subtilis, to destroy which a much higher temperature is necessary. As some kinds of soured milk, such as " varenetz," " yahourth," " leben,'! etc., are prepared from boiled milk, ' See Grasberger and Schattenfroh, Archiv.fiir Hygiene, 1902, yoL xlii, p. 246. N 178 THE PROLONGATION OF LIFE it might be supposed that they fulfil the conditions neces- sary fo.- prolonged use. A closer examination, however, makes us reject them. Boiled milk, to make it undergo the lactic fermentation properly, must have added to it a prepared ferment. What is necessary is not merely rennet, as was formerly sup- posed, but a number of organised ferments, that is to say, microbes. In the preparation of these soured milks, a leaven is employed, one of the names of which is " Maya," and which contains not only lactic microbes, but several others. MM. Rist and Khoury ^ have come to the conclu- sion that the Egyptian " leben " contained a flora com- posed of five species, three of which are bacteria and two yeasts. The bacteria produce lactic acid and the yeasts alcohol. Although the result is that " leben " is a nearly solid substance, whilst kephir is a liquid, the two are closely similar. In both cases we have to do with coincident lactic and alcoholic fermentations, and my remarks regarding kephir apply equally well to the Egyptian " leben." Through the agency of Prof. Massol of Geneva, I have obtained a specimen of the Bulgarian " yahourth." Work- ing with his pupil, M. Grigoroff, M. Massol ^ has isolated several microbes from this milk, amongst these being a very active lactic bacillus. The same soured milk has been studied in my laboratory by Drs. M. Cohendy* and Michelson. They found in it a very powerful lactic fer- ment, which has been named the Bulgarian bacillus. This was the microbe employed in the experiments of M. B61on- owsky, to which I have already referred. More recently, it has been carefully investigated from the chemical point of ' Annales de PInsiitut Pasteur, 1902, p. 65. ' Revue mMicale de la Suisse romande, 1905, p. 716. ' Comptes rendus de la Soc. Biologique, March 17th, 1906. LACTIC ACID AND PUTREFACTION 179 view by MM. G. Bertrand and Weisweileri at the Pasteur Institute. It proved to be an extremely active producer of lactic acid, supplying 25 grammes per litre of milk. The other acids which this bacillus produces, such as succinic and acetic acids, are formed only in very small quantities (about 50 centigrams a litre). Formic acid is produced only in traces. On the other hand, the Bulgarian bacillus forms neither alcohol nor acetone, two frequent products of bacterial fermentation. The bacillus also differs from other lactic ferments inasmuch as it has no action on albumin- oids (casein, etc.), nor on fats. All these qualities make the Bulgarian bacillus much the most useful of the microbes which can be acclimatised in the digestive tube for the purpose of arresting putrefactions and pernicious fermenta- tions, such as the butyric fermentation. As in all the known soured milks (yahourth, leben, pro- stokwacha, kephir, and koumiss) the lactic bacilli are asso- ciated with a rich flora in which pernicious microbes may be met (such as the red torula^ a microbe which predis- poses to cholera and typhoid fever, which I found in the leaven of yahourth, bought in Paris), it is necessary to work out a method by which good curdled milk can be produced with the aid of pure cultures of the lactic microbes. It was the obvious course to begin with the Bulgarian bacillus, as that is known to be the best producer of lactic acid. It coagulates milk rapidly, giving it a strongly acid flavour, but it often also gives a disagreeable taste of tallow. It is true that after it has been kept for a long time in the laboratory in the form of pure cultures in sterilised milk, the bacillus loses to a large extent its power of saponifying fats, the taste of the curdled milk being then more agree- able. If necessary, therefore, soured milk prepared exclu- * Annales de PInstitut Pasteur, 1906, p. 977. N & i8o THE PROLONGATION OF LIFE sively with the Bulgarian bacillus can be used. In practice, however, it is useful to associate with it another lactic microbe, known as the paralactic bacillus, as the latter, although producing less lactic acid than the Bulgarian bacillus, does not break up the fats and gives the curdled milk a very pleasant flavour. As it is undesirable to absorb too much fatty matter, it is necessary to prepare curdled milk for regular use from skimmed milk. After the milk has been boiled and rapidly cooled, pure cultures of the lactic microbes are sown in it, in sufficient quantities to prevent the germina- tion of spores already in the milk and not destroyed in the process of boiling. The fermentation lasts a number of hours, varying according to the temperature, and finally produces a sour curdled milk, pleasant to the taste and active in preventing intestinal putrefaction. This .milk, taken daily in quantities of from 300 to 500 cubic centi- metres, controls the action of the intestine, and stimulates the kidneys favourably.^ It can therefore be recommended in many cases of disorder of the digestive apparatus, of the kidneys, and in several skin diseases. The Bulgarian bacillus taken from yahourth or from soured milk, prepared from pure cultures of lactic microbes, can live in warm temperatures, and, as has been shown by Dr. Cohendy, is able to take its place in the intestinal flora of man. Soured milk, prepared according to the receipt which I have given, has been analysed by M. Fouard, an assist- ant at the Pasteur Institute. When it was ready to be taken, M. Fouard found in it about 10 grammes of lactic acid per litre. Moreover, a large proportion (nearly 38 per cent.) of the casein had been rendered soluble during the fer- ' Soured milk can be taken at any time of the day, with or in between meals. LACTIC ACID AND PUTREFACTION i8i mentation, which shows that its albuminous matter is pre- pared for digestion much as in kephir. Of the phosphate of lime (which is the chief mineral substance of milk) 68 per cent, was rendered soluble during the fermentation. These facts all confirm the utility of the soured milk prepared from pure cultures of lactic bacteria. Those persons who, from some reason or other, cannot take milk, may swallow the bacilli in a pure culture with- out milk. However, as the microbes need sugar to produce lactic acid, it is necessary to take with them a certain quantity of sweet food (jam, sweet-meats, and especially beetroot). The Bulgarian bacillus produces lactic acid not only from milk sugar, but also from many other sugars, for in- stance, cane sugar, maltose, levuloseand especially glucose. Cultures of the bacillus can be made not only in milk, but in vegetable broths, or broths of animal peptone to which sugar has been added. The cultures can be taken in a dry form (powders or tabloids), or in the liquid in which the bacilli had themselves been developed. A reader who has little knowledge of such matters may be surprised by my recommendation to absorb large quan- tities of microbes, as the general belief is that microbes are all harmful. This belief, however, is erroneous. There are many useful microbes, amongst which the lactic bacilli have an honourable place. Moreover, the attempt has already been made to cure certain diseases by the adminis- tration of cultures of bacteria. M. Brudzinsky^ has used cultures of lactic microbes in certain intestinal diseases of infants, whilst Dr. Tissier^ has used them in similar affections of infants and adults. ' Jahrbuch fiir Kinderheilkunde, N. F. 12 Ergansungsheft, 1900. 2 Annates de Flnstitut Pasteur, 1905, p. 295 ; Trilmne medicate, Feb. 24th, 1906: 1 82 THE PROLONGATION OF LIFE From the general point of view of this book^ the course recommended consists of the absorption either of soured milk prepared by a group of lactic bacteria, or of pure cultures of the Bulgarian bacillus, but in each case taking at the same time a certain quantity of milk sugar or saccharose. For more than eight years I took, as a regular part of my diet, soured milk at first prepared from boiled milk, inoculated with a lactic leaven. Since then, I have changed the method of preparation and have adopted finally the pure cultures which I have been describing. I am very well pleased with the result, and I think that my experiment has gone on long enough to justify my view. Several of my friends, some of whom suffered from maladies of the intes- tine or kidneys, have followed my example, and have been well satisfied. I think, therefore, that lactic bacteria can render a great service in the fight against intestinal putre- faction. If it be true that our precocious and unhappy old age is due to poisoning of the tissues (the greater part of the poison coming from the large intestine inhabited by num- berless microbes), it is c-lear that agents which arrest intes- tinal putrefaction must at the same time postpone and ameliorate old age. This theoretical view is confirmed by the collection of facts regarding races which live chiefly on soured milk, and amongst which great ages are common. However, in a question so important, the theory must be tested by direct observations. For this purpose the numer- ous infirmaries for old people should be taken advantage of, and systematic investigations should be made on the rela- tion of intestinal microbes to precocious old age, and on the influence of diets which prevent intestinal putrefaction in prolonging life and maintaining the forces of the body. It can only be in the future, near or remote, that y/e shall LACTIC ACID AND PUTREFACTION 183 obtain exact information upon what is one of the chief problems of humanity. In the meantime, those who wish to preserve their intel- ligence as long as possible and to make their cycle of life as complete and as normal as is possible under present conditions, must depend on general sobriety and on habits conforming to the rules of rational hygiene. PART V PSYCHICAL RUDIMENTS IN MAN I RUDIMENTARY ORGANS IN MAN Reply to critics who deny the simian origin of man — Actual existence of rudimentary organs — Reductions in the structure of the organs of sense in man — Atrophy of Jacob- son's organ and of the Harderian gland in the human race Several critics of The Nature of Man have protested against my theory of the simian origin of man. Some of these found my arguments unsatisfactory and unconvinc- ing. Others have attacked generally my suggestion that some anthropoid had been suddenly transformed to a primitive human being. It is true that so long as we have little paljeontolo- gical evidence as to the actual descent of man, we cannoi discuss the subject without the aid of hypotheses. I think, however, that recent additions to knowledge confirm the theory of the descent of man in a way that ought to influ- ence the most resolute opponents. I have in mind chiefly the arguments supplied by the embryology of anthropoid apes, and by the investigation of their blood. None the less, there are still many authors who maintain their oppo- sition. One of my critics, Dr. Jousset,^ enumerates certain differences in the structure of the skeleton in man and apes, and concludes that these radically separate man from apes. * La nature humaine et la philosophie optimiste, Paris, 1904. RUDIMENTARY ORGANS IN MAN 185 No one has ever doubted that man was not identical in structure with the anthropoid apes, or that he differs from them in several characters of the skeleton and of many other organs. The differences, however, do not justify any radical separation of the two. The unusual length of arm, upon which my opponents throw so much weight, is in harmony with the mode of life of apes, as these climb on trees and walk on all four limbs. The difference between apes and Europeans in length of arm is certainly consider- able, but is much less in the case of some lower races, such as the Veddahs. In the Akkas of Central Africa, the arms are so long that the hands nearly reach the knees. The foetus of Europeans also shows an unusual length of arm, probably an ancestral feature. It is only after birth that the arms become relatively shorter. All the other characters different in man and the apes, are equally secondary. On the other hand, just as apes differ amongst themselves, so also, the different races show differences often strongly marked. M. Michaelis,' in a comparative study of the muscular systems of monkeys, has made known many details of the musculature in the orang-outan and the chimpanzee, and it appears from his investigations that, although there are some differences between these two apes, they are both closely similar to man. There are man^ variations in the muscular structure of man, and these find parallels in the muscles of apes. This is also the case with other abncrmalities of structure, some of which resemble the condition in mammals much lower than apes. An example of this is the presence of addi- tional pairs of nipples, arranged-symmetrically on the sides of the chest and occasionally found in human beings. A similar abnormality has been found in some monkeys, and ' Archiv.f. Anat. u. Physiol., Attatom. Abtheil, 1903, p. 205. 1 86 THE PROLONGATION OF LIFE the best explanation of such an occurrence is that monkeys, like man, are descended from mammals which possessed several pairs of mammary glands. The large number of abnormalities and rudimentary organs which may be found in man affords important evidence in favour of the descent of man from lower animals. Some authors, however, have tried to dispute this view and even deny the existence of rudimentary organs. M. Brettes,^ arriongst my opponents, has brought together most facts upon this matter, with the object of proving that such organs fulfil some function indispensable to the body and bear witness to the existence of a general plan of organisation. My opponent, however, confines himself to general propositions, laying much stress on a law of "the subordination of organs" without proving that rudimentary organs have an actual function. In The Nature of Man I remarked on the uselessness of the wisdom teeth, which are not cut until long after childhood and which are useless in mastication. In many human beings these teeth never cut through the gum, and their absence is no disadvantaige. TJiis is a typical case of a rudimentary organ. To maintain the contrary it would be necessary to prove that the wisdom teeth fulfil an indis- pensable function and that their absence was in some way harmful to the organism. No one has been able to show this. The mammary glands in males are another case of rudi- mentary organs. The function of these, of course, is well known in females, but it is only in the rarest cases that they are active in males. The organs of sense supply many cases of rudimentary structures. Animals which live in caves, in the dark, do not discern objects by sight, and in these cases the eyes are ' L'univers et la vie, p. 592. RUDIMENTARY ORGANS IN MAN 187 rudimentary. It is quite impossible to deny the existence of rudimentary organs. They are extremely important guides to us in our investigation of the past history of the human race. The comparative study of the organs which are rudimentary in man and more or less well developed in lower animals is of fundamental importance in the problem of our origin. The higher apes, or anthropoids, display reduction in some parts of the organs of sense. The organ of smell, for instance, is much less developed in them than in many other animals. Man has inherited the imperfect condition of this organ, and his sense of smell is much less developed than that of mammals which are lower in the scale of life. Man, however, because of his intelligence, has been able to tame domestic animals, such as dogs, ferrets, and pigs, and to make use of their acute sense of smell for tracking game or obtaining edible plants. The imperfect condition of the sense of smell in man in other cases is well re- placed by his mental powers. He no longer recognises the approach of an enemy by the sense of smell, in order that he may take flight, because he has better means of defence than those of animals. It is not surprising, therefore, that the olfactory apparatus of man is much reduced as com- pared with that of lower mammals. In apes and man the nasal region of the head is much smaller than in their mammalian ancestors, and in the deep-lying parts of the system there are corresponding differences. Most mammals, for instance, and the dog in particular, have four turbinal bones, the purpose of which is to increase the surface of the mucous membrane of the nose, whilst in man there are only three, one of which is rudimentary. The olfactory apparatus in most mammals contains a well-developed portion known as the organ of Jacobson, 1 88 THE PROLONGATION OF LIFE the probable function of which is to appreciate the flavour of food in the mouth. In man, this organ is in a rudi- mentary condition and cannot fulfil its function, as it is devoid of its proper nerve. This remnant, now useless, gives us information as to the evolution of the organ of smell in man. In the human foetus, Jacobson's organ is not only better developed than in adult man, but it is also provided with a stout nerve trunk, which disappears to- wards the end of embryonic life. The organ, however, cannot perform any^ olfactory function. The human foetus, moreover, possesses five turbinals which later on become reduced to three, and of these only two develop completely. The history of the evolution of the organ of smell, as it has been made out by comparative anatomy and embry- ology, links this apparatus in man with the corresponding organs of other mammals by means of these useless rudi- ments, which, however, are important evidence in scien- tific theory. The auditory apparatus also has become reduced in man. Many animals, in the struggle for existence, require a very acute sense of hearing, more so than man or some of the most intelligent mammals. We have all seen how horses raise their ears to hear better when there is the slightest sound near them. Monkeys and man have lost this power, and man sometimes tries to supply the defect by artificial means. When a lecturer, for instance, is not speaking sufficiently loud some of the audience put their hands to their ears, making a kind of trumpet which serves to catch the sound. The human external ear is supplied with muscles, but in most cases these are too feeble to move it. In very rare cases persons can move their ears, the muscles inserted to the shell in most of us being mere rudiments of those that existed in our ancestors. RUDIMENTARY ORGANS IN MAN 189 In the organ of sight, the little fold in the inner angle of the eye, known as the semilunar fold, is of special interest. This membrane is a useless vestige of a struc- ture much better developed in lower mammals. In the dog it is present as a small third eyelid, supported by a special cartilage provided with a secreting gland, known as the Harderian gland. In birds, reptiles and frogs, the corresponding structures are much better developed. Everyone has seen the delicate membrane which, in the case of a bird, may shoot out from the inner angle of the eye and cover the whole of the exposed part of the eyeball (nictitating membrane). In these animals, the eye is pro- tected by this third lid, which has its own muscles. As in the dog, this third eyelid of birds and lower vertebrates is generally provided with a large Harderian gland, which produces a liquid secretion like tears. In most monkeys, this apparatus is much reduced. Many of them have still a small Harderian gland and a weak third eyelid. In man, as I have already said, there are only vestiges of these organs, the gland being almost atrophied and the third eyelid represented only by an in- significant crescentic fold. In the lower races the fold sometimes contains a small cartilage. Giacomini found it twelve times in sixteen negroes, whilst in 548 white people it was found only in three cases. The interpretation of these facts is not doubtful. This little fold is the last vestige in use of an organ which was , , useful only in our remote ancestors. The organs of reproduction in the human race also show a number of rudiments. There remain even traces of a hermaphrodite condition, a very low degree of organisa- tion, going back to extremely rem.ote ancestors. The evidence given by the very large number cf abnormalities I90 THE PROLONGATION OF LIFE that are found fn thes& organs makes it clear that, in the long period of the evolution of the human race, they have been subjected to a series of modifications. Thus, for in- stance, there is occasionally present in women a form of uterus resembling that of the lower mammals, or even the double uterus of marsupials. The evolution of man has been dominated by the great development of the brain and of the intelligence, and man, accordingly, has lost many organs and functions which were of use in his more or less remote ancestors. 11 HUMAN TRAITS OF CHARACTER INHERITED FROM APES The mental character of anthropoid apes — Their muscular strength — Their expression of fear — The awakening of latent instincts of man under the influence of fear The facts of which I have given a r^sumd serve to show that evolution always leaves definite traces indicating its successive stages in the form of rudiments. It is probable, therefore, that the pre-human mental functions or psycho- physiological qualities, which have so long a history behind them^ have also left more or less appreciable traces. These, however, must be more difficult to find than rudi- mentary organs which can be made visible by dissection. If we turn first to the animals most nearly related to man, we find that the living anthropoid apes show in the clearest way their close relationship with the human race, and suggest that their kinship with our remoter ancestors must be even greater. The anthropoid apes alive to-day are animals inhabit- ing chiefly virgin forests, and feeding on fruits and shoots, although they do not despise eggs or even little birds. To satisfy their wants, they climb with the greatest ease, Orang-outans and chimpanzees climb slowly and carefully, whilst gibbons show a greater agility and more perfect acrobatic power. They may be seen throwing themselves 192 THE PROLONGATION OF LIFE from branch to branch across spaces of forty feet with the greatest precision. They play at the top of very tall trees, hardly grasping the branches through which they pass, making leaps of from twelve to eighteen feet for hours together with little apparent exertion. To give an idea of the dexterity and swiftness of gibbons, Martin took the case of a female which he ob- served in captivity. One time she hurled herself from a perch across a space at least twelve feet wide, against a win- dow which one would have thought would have been immediately broken. To the great surprise of the spec- tators it was not broken. The gibbon seized with her hands the narrow board between the panes, and then in an instant twisted herself round and jumped back to the cage she had left, performing this manoeuvre with great strength and the most marvellous precision. •The muscular force implied in the above narrative is possessed by all the anthropoid apes. Battel, an English sailor who gave the first description of the gorilla in the beginning of the 17th century, stated that the strength of that animal was so great that ten men could hardly master an adult specimen. The other anthropoids, although not so strong as the gorilla, nevertheless display surprising force. Edouard, the young male chimpanzee which I used jn my experiments on syphilis, struggled so much at the least touch that it took four men to master him. I had to ■^ive up allowing him to leave his cage because there was no way of getting him back to it. Even quite young chimpanzees, females not yet two years old, cannot be handled easily. Although they are very friendly, my specimens used to resist with all their strength when it was necessary to put them back in their cages for the night. Two men had much ado to shut them up. CHARACTER INHERITED FROM APES 193 Notwithstanding this great muscular force, the anthro- poid apes are cowardly. They have no idea of their strength, but fly from the approach of the slightest imagined danger. My young chimpanzees, although their teeth and muscles were already formidable weapons, showed the greatest fear when I put with them animals even so weak and harmless as guinea-pigs, pigeons and rabbits. Mice frightened them very much at first, and it took them a con- siderable time before they got over their fear of so insig- nificant an enemy. When living in a state of nature the anthropoid apes scarcely ever assume the offensive. " Though possessed of immense strength," wrote Huxley,^ "it is rare for the Orang to attempt to defend itself, espe- cially when attacked with fire-arms. On such occasions he endeavours to hide himself, or to escape along the top- most branches of the trees, breaking off and throwing down the boughs as he goes." Savage^ wrote of chimpanzees that ' ' they do not appear ever to act on the offensive, and seldom, if ever really, on the defensive." When a female was surprised on a tree with her young ones "her first impulse was to descend with great rapidity and make off into the thicket." ^ The gorilla, the strongest and most ferocious of the apes, has sometimes been observed to take the offensive. Savage, quoted by Huxley, said that " they are exceedingly ferocious, and always offensive in their habits, never run- ning from man, as does the chimpanzee. The females and young, at the first cry, quickly disappear. He (the male) then approaches the enemy in great fury, pouring out his horrid cries in quick succession."* Only males ' Huxley, Maris Place in Nature. Collected Essays, vol. vii, p. 54. s Ibid., p. 60. 3 IHd., p. 62. 1 Ibid., p. 67. 194 THE PROLONGATION OF LIFE take the offensive, nor can this be of frequent occurrence, as one of the most recent observers, Koppenfels,^ states that "the gorilla never attacks man spontaneously; he tries to avoid him , and, as a rule, takes to flight as soon as he sees a man, uttering peculiar guttural cries." Which of these characters are preserved in the human race ? Man is naturally feebler and less of a gymnast than the great apes, but his disposition is cowardly. One of the eairliest signs of mental activity in an infant is the fear of surrounding circumstances. The smallest change in its balance or its being put in a bath cause it to show signs of real terror. Later on, it is alarmed when it sees any kind of animal, exactly in the fashion of a young chimpanzee. The most harmless spider is enough to frighten it. Although mental culture subdues fear to a large extent, fear reveals itself more or less strongly from time to time? and it is on such occasions that we may find in the human being psychological relics of his ancestors. An analysis of fear is of special interest. The first result of the emotion of fear is flight. Con- sciousness of danger sets our limbs in motion, and our instinctive desire to escape displays itself even when flight is more dangerous than what we wish to avoid. At the first alarm of fire in a public building, people rush towards the exits and in so doing often perish from their wish to escape. Even in the extreme of terror, the desire of flight is one of the earliest impulses. Mosso, a well-known Italian physiologist, in a monograph on fear, relates that when a Calabrian brigand was sentenced to death "he uttered a sharp cry, heart-rending and terrible, looked around him as if he were eagerly seeking for something, and then stepped backwards as if to fly, and threw himself ' M^ndgaux, Les Manmmifires, p. 24. CHARACTER INHERITED FROM APES 195 against the wall of the court, writhing, with arms out- stretched, scratching at the wall as if he were trying to break through it." Although in such a case it was futile and often is harmful, the instinct of flight from danger is inherited from ancestors from a time when it served to save life. Attempts to escape are not the only signs of fear. There is often a trembling fit which would make flight impos- sible. In JMosso's case of the Calabrian brigand, "after his struggles, cries and contortions, he fell on the ground in a motionless heap, like a wet rag ; he became pale and trembled more than I have seen any other person tremble ; his muscles seemed changed into a soft and quivering jelly." This condition of trembling inertia is another » legacy from animals. Quivering of the muscles often manifests itself in terrified animals. Darwin ^ wrote of it, "trembling is of no service, often of much disservice, and cannot at first have been acquired through the will, and then rendered habitual in association with any emotion." The phenomenon seemed to him obscure and difficult to explain, a view shared by Mosso. The trem- bling of the musculature of the body is a generalised and exaggerated form of the movements of the cutaneous muscles in the condition known popularly as "goose- skin." The latter, however, is a relic of an adaptation useful to some animals. The hedgehog rarely takes to flight at the approach of danger, but stands still, and using strongly developed muscles, rolls itself into a ball. In birds and many mammals, the muscles of the skin cause erection of the feathers or hairs. These movements often are performed during fright, and according to Darwin, ' Darwin, Expression of the Emotions in Man and Animals, 1873, p. 67. O 2 196 THE PROLONGATION OF LIFE serve not only to warm the skin, but sometimes to make the animal appear larger and more terrifying to enemies. Fear and cold alike cause contraction of the superficial blood-vessels, and, in man, excite the contraction of the minute rudimentary muscles inserted to the roots of the hairs. " Goose-skin " is caused by the contraction of these muscles, the condition being a functional rudiment, no longer serving to warm the skin nor to make the body appear larger. In a few exceptional cases, "goose-skin" can be produced voluntarily. In the normal condition, the rudimentary cutaneous muscles of man are immobile, and it requires some special stimulation to set them in action. Fear, which is occasionally able to excite the contrac- tion of the involuntary muscles, also stimulates other muscles against the will. Under the influence of emotions that powerfully affect the nervous system, and particularly under that of fear, contractions of the bladder and intes- tines may be so violent that it is impossible to prevent the voiding of their contents. Accidents of this kind are not infrequent in the case of youthful candidates at examina- tions. Mosso relates of a friend, a volunteer in the war of 1866, that he was seized with terror during a battle and that the utmost efforts of his will failed to make his body endure the terrible spectacle. The involuntary action of the bladder and intestines during fear is a legacy from animals. The phenomenon is common in dogs and monkeys. Chimpanzees, when laid hold of, discharge their urine and faeces. At Madeira I had an unusually cowardly Cercopithecus monkey which when at all alarmed discharged the contents of the rectum. Quite possibly such a mechanism was useful for the pre- servation of the individual. The emission of various kinds of excretions is of use in the struggle for existence. In CHARACTER INHERITED FROM APES 197 that way the fox drives the badger from its earth and takes possession of it, whilst polecats and skunks defend them- selves against more powerful carnivorous animals by dis- charging on them foetid secretions. Instinctive fear is therefore a very powerful stimulant, awakening functions which are rudimentary and almost completely extinct. Sometimes it sets in operation mechanisms which have long been paralysed. Pausanias gives an example of a dumb young man who recovered his speech when he was terrified by seeing a lion. Hero- dotus relates that the son of Croesus, who was dumb, on seeing a Persian about to kill his father^ cried out : "You must not kill Croesus," and from that time onwards was able to talk. These ancient narratives have been con- firmed by many modern observations. A woman, for instance, who had been dumb for several years, on seeing a fire, was terrified and cried out suddenly " Fire ! " after which her speech was restored. Such are cases of the awakening of a function which has been arrested only for several years. But fear can bring into activity other mechanisms which have been inactive from time im- memorial. Many different kinds of animals can swim instinctively. This is true in the case of most birds and mammals. There are some species which show a repugnance to water, but none the less swim well enough if they are thrown into it. Cats shun water as much as possible, but, none the less, can swim quite easily. Historians relate that Han- nibal had great difficulty in getting his elephants to cross the Rhone. Some females were ferried across first, upon which the other elephants threw themselves into the water to pursue them and swam across the river without any difficulty (Lentheric, Le Rhone, 1892, p. 8i). The lower monkeys can swim without, being taught, but 198 THE PROLONGATION OF LIFE the anthropoid apes have lost this power, and man also is without it. M. Volz^ states that the different species of gibbons which live in Sumatra are separated by rivers. Their inability to swim makes these a complete barrier. It is probable that the lower races, in this respect, are better endowed than we are. It is said that in the case of negroes, children run to the sea or to rivers almost as soon as they leave the cradle, and learn to swim almost as quickly as to walk.^ In the case of white people, many find it very difficult to learn to swim, and it is at least certain that swimming is not instinctive as in the case of our animal ancestors. Christmann,^ the author of a treatise on swimming, states that the reason of man is a worse guide than the infallible instinct of the animal. Fear is able to stifle reason and to allow the instinct to come into play. It is known that children or adults may be taught to swim by throwing them into the water. Under the influence of fear, the instinctive mechanism inherited from animals awakens, and man soon becomes a swimmer. There are some teachers of swimming who use this method success- fully. I have myself known an individual who learnt the art in that way, and M. Troubat, librarian at the Inter- national Library, has informed me that one of his friends, a journalist who died at Noyon several years ago, bathed in the Seine one evening at Neuilly when he could not swim. Unexpectedly finding himself beyond his depth, a sudden movement of fear saved him. Since then, he said, he knew how to swim. Just as there are cases in which terror provokes flight, 1 Biologisches Centralblatt, 1904, p. 475. * J. de Fontenelle, Nouveau manuel complet des nageurs, Paris, 1837, p. 2. * La natation et les bains, Paris, 1887. CHARACiER INHERITED FROM APES 199 and others in which it causes an arrest of motion, so also fear may do a disservice to a swimmer. Those who employ fear as a means of teaching to swim, know that they must intervene if there is real danger. It is true, none the less, that up to a certain point fear can awaken func- tions which have been atrophied for numberless genera- tions, and that we can learn from it something as to the, evolution of the human race. Ill SOMNAMBULISM AND HYSTERIA AS MENTAL RELICS Fear as the primary cause of hysteria — Natural somnam- bulism — Doubling of personality — Some examples of som- nambulists — ^Analogy between somnambulism and the life of anthropoid apes— The psychology of crowds — Importance of the investigation of hysteria for the problem of the origin of man The Study of fear is interesting in other respects than those with which I have been dealing. It is also a primary cause of the obscure and complicated phenomena of hysteria. Thus, for instance, amongst twenty-two hysterical women observed by Georget^ the primary causes were : terror, 13 cases; extreme grief, 7 cases; extreme annoyance, one case. A patient of M. Pitres, of Bordeaux, first exhibited hysteria after being extremely terrified. A man with a tame bear had come to the village. The patient went to see the per- formance and elbowed her way through the crowd until she got to the front row. The bear, whilst dancing, passed so close that its cold muzzle touched the cheek of the young girl. Marie — for that was the patient's name — was terri- fied. She ran quickly home, and almost on her arrival fell on her bed in an attack of convulsion and extreme delirium. Since then the attacks have been repeated many times, and the delirium associated with them always turns upon Ihe terror caused by the bear touching her. ^ Quoted by M. Pitres in Leqons cliniqttes sur Fhystdrie, 1891, vol. i. SOMNAMBULISM AND HYSTERIA 201 A hysterical woman at the Salp^tri^re is haunted by terrifying dreams. She thinks someone is trying to murder her, or to cut her throat, or that she is falling into water, and she keeps crying for help.^ Some of the most curious phases of hysteria are the para- doxical and extraordinary cases of so-called natural som- nambulism, in which the patients, whilst asleep, perform all sorts of acts of which they remember nothing in their waking hours. Cases of duplication of personality are also known, in "which the patients live in two different states without, in one of these, having the slightest remem- brance of what takes place, in the other. One of the most curious observations was that of the somnambulist who became enceinte whilst in her second state. In her first, or normal condition, she was ignorant of the reason of her physical changes, although in the second state she knew about it quite well and spoke freely of it (Pitres, op. cit. 11, 215). In the state of natural somnambulism the patients gene- rally reproduce the normal acts of their daily life which they have acquired the habit of performing unconsciously. Artisans devote themselves to their manual work, semp- stresses begin to sew, maid servants brush shoes or clothes, lay the table and so forth. Educated persons devote them- selves to intellectual work to which they are accustomed. Clergymen have been known to compose their sermons in the somnambulistic condition, and to read them over to correct mistakes in style or in spelling. However, besides somnambulists who during slumber simply repeat the usual acts of their life, there are others who do special things to which they are unaccustomed. ' Bourneville et Regnard, Iconographie photographiqtte de la Sal- pitriire, 1879-1880, vol. iii, p. 50. 202 THE PROLONGATION OF LIFE It is these cases which are most interesting from my point of view. I shall take one case which has been specially well reported. A hysterical patient, a girl of 24 years of age, was admitted as an in-patient to the hospital Laennec. One Sunday, she got up about one o'clock in the morning. The night watchman, who was alarmed, went for the nighi doctor, who witnessed the following scene. "The patient went to the staircase leading to the nurses' quarters, then suddenly turned round and walked towards the wash- house. The door of that being closed^ she then groped for a time and turned towards the women's dormitory in which she had formerly slept. She went up to the top of the house where this dormitory v.'as, and when she got on the landing, opened a window leading to the roof, went out of the window, walked along the gutter, under the horrified eyes of the nurse who followed her and who did not dare to speak to her, went in again by another window and went down the stairs." " It was at this moment that I saw her," said the night doctor; " she was walking noise- lessly, her gait was automatic, her arms hanging by her sides, a little bent, the head erect and fixed, her hair disordered, her eyes wide open ; she seemed like some strange apparition."^ This is obviously the case of a hysterical subject, who in a normal condition was not accustomed to climb upon roofs and walk along the gutters. Another observation, reported by Charcot, related to a young man, seventeen years old, the son of a large manu- facturer, and of good address. Tired out by working for his final examination, he had gone to bed early. Some time later he rose from the bed in his college dormitory, ' Stephanie Feinkind, Du somnambulisnte dit naturel, Paris, 1893, P- SS- SOMNAMBULISM AND HYSTERIA 203 went out by a window^ and without accident climbed on tiie roof and took a long and dangerous walk along the gutters. He was awakened before any accident occurred (Feinkind, p. 70). A case observed by Dr. Mesnet and M. Mottet was still more interesting. A lady thirty years old and extremeh- hysterical got out of bed in the night, "dressed herself, completed her toilet without help, removed the furniture in her way without stumbling against it. She was in- different and idle by day, but strenuous at night in perform- ing the most varied acts. I have seen her walking about in her rooms, opening doors, going down to the garden, leaping on seats with the utmost agility, running about, in fact doing all these things much better than in her waking hours, in which she got about only slowly and with aid" (Feinkind, p. 84). Horst has related an extraordinary incident which took place in the sixteenth century. "A soldier walked in his sleep to a window, and with the help of a rope climbed a high tower, secured a jackdaw's nest with its young birds, and regained his bed, where he remained asleep until the morning." 1 Unfortunately there are not sufificiently de- tailed facts regarding this incident, and for fully described cases we must return to modern times. Dr. Guinon has related one case in ample detail. A man thirty-four years of age, by occupation an interpreter, was taken into hospital for hysterical attacks. " One night soon after he came under the care of the physicians, this patient, towards one o'clock in the morning, suddenly arose from bed, threw open a ' window and jumped across the sill into the courtyard of the hospital. The attendants on duty ran after him, and saw him hurrying away, undressed and carrying a pillow ■ Dictionnaire des sciences mddicales, 1821, vol. liij p. 119. 204 THE PROLONGATION OF LIFE in his arms. He traversed a series of gardens and walks, with the topography of which he was unacquainted, climbed a ladder and got on the roof of the hydrotherapeutic estab- lishment, up and down which he proceeded to run with the greatest agility. Sometimes he stopped in his flight and rocked the pillow he was carrying, kissing and soothing it as if it were a child. Then he retraced the route he had taken." On being questioned next morning, he had not the faintest remembrance of his nocturnal exploit. "A similar fit came on him five or six times "(Feinkind, p. io8). The same patient, "after having turned over in bed several times, seized a pillow and held it to his breast. He then got out of bed, and, in his nightgown, ran through the dormitory to a door leading to the lavatories. He opened the door, readily but with violence, and entered one of the closets. Then, still holding the pillow against his chest with one arm, by a gymnastic feat both difficult and dan- gerous, yet which he performed with the utmost precision, using his feet and the free arm, he got hold of the edge of the frame of an open window, through which he swung himself to the sill, alighting on both feet, after which, preserving the pillow carefully from contact or shocks, he jumped to the ground (the infirmary ward was on the ground floor). He then ran quickly to the opposite corner of the courtyard, passing the whole length of the great building at full speed, holding the pillow carefully. By a path which led round the building, he reached a corner where there was a tower supporting a great water- tank. A kind of metallic ladder, placed almost vertically and with rounded steps, led up the side of the tower to a sort of observation-landing which at one point was adja- cent to the edge of the roof of the bath-house. " The patient set himself to climb this ladder without any SOMNAMBULISM AND HYSTERIA 205 hesitation, holding on by his free hand and placing his naked feet on the rounded steps with extreme precision. When he reached the nearest point to the roof of the bath- house he leapt upon that, and at a running pace climbed the zinc roof to the crest, looking round him from time to time to see if his imaginary pursuers were near. He ran along the crest which was so narrow that his feet had to be placed alternately on either side on the slopes of the steep-pitched roof, a performance so dangerous that none of the officials would follow him, and which none the less he performed with complete assurance and without a single slip. " When he reached the middle of the building he sat down on, the crest of the roof, leaning against a ventilating chimney. He then took the pillow which he had been carrying carefully, placed it on his knees with a corner against his shoulder, and began to rock it as if it were a child, crooning to it, stroking it with his hand or with his cheek that he pressed gently against the corner. From time to time his eyebrows contracted and his looks hard- ened, and he gazed around him as if he were being pursued or watched, then gave a growl of rage, and took to flight again, carrying the pillow on his dangerous path. All the time he kept speaking, but we could not hear what he said. He saw nothing that was not in his dream ; he did not understand when his name was called aloud; but he could hear, for at the slightest sound near him he rushed off again as if his pursuers were upon him. This episode lasted about two hours, during which he had climbed over all the roofs in the vicinity, defying our pursuit of him " (Feinkind, pp. 106-112). I could give other similar cases, but I think that I have shown sufficiently that man, when in the condition of 2o6 THE PROLONGATION OF LIFE natural somnambulism, exhibits qualities that he does not possess in the normal state, becoming strong, adroit, and a good gymnast, like his anthropoid ancestors. The close resemblance between the manoeuvres of Martin's gibbon, which I described earlier in this chapter, and the dangerous exploits of some sleep walkers is most striking. The impulses to climb on roofs and poles, to run along in rain gutters, to climb a tower to take a bird's nest, are characteristic examples of the instinctive actions of climb- ing animals, like the anthropoid apes. Dr. Barth ^ defines somnambulism as " a dream with exaltation of the memory and automatic action of the nervous centres, without volun- tary and conscious control." "The striking exaltation of the memory is the dominating condition. The extreme exactness of the memory of places displayed by the som- nambulist makes us understand how he performs his noc- turnal wanderings, doing almost without the aid of his senses numberless deeds of which he would be practically incapable in a waking condition." However, as such a patient performs new acts which he has never accom- plished before in his own individual life, we must suppose that the exaltation of memory includes extremely ancient facts, dating perhaps from the pre-human period. Man has inherited from his ancestors a number of mechanisms of the brain, the activity of which is inhibited by restraints which have been developed later. Just as man possesses mammary glands which under ordinary conditions cannot secrete milk, so also, in his brain, there are contained groups of cells which are inactive in the normal condition, but, also, just as in some exceptional cases man and the males of several species of mammals are able to give milk, so also in abnormal conditions the atrophied mechanisms of other nervous centres begin to act. ' Du Sommeil non nature!, Paris, 1886. SOMNAMBULISM AND HYSTERIA 207 The secretion of milk by males is a return to an extremely ancient condition in which both sexes were able to nourish the young ; so, also, the gymnastic feats and the extraor- dinary strength of somnambulists are a return to a normal condition much less remote from us than lactation in males. It is curious to find that, in some cases, natural som- nambulism is associated with power to move the shell of the ear. I know two brothers, who, when they were young, used to walk in their sleep in the most typical way. One of them, a chemist, used to climb on a high cupboard, or simply walk about in the room. The other brother, a sailor, in a fit of somnambulism, climbed to the top mast of a sailing ship. These brothers, who were somnambu- lists, had the cutaneous muscles extremely well developed and were able to move their ears voluntarily. In this case the abnormality was hereditary in the family, and the two daughters of one of the brothers were also somnambulistic and had control over the muscles of the ears. Here, then, is a case of the simultaneous recurrence of two characters of our ancestors : mobility of the ear and agility in gymnastic feats. M. Barth characterises the somnambulist as "a living automaton in whom conscious will is for the time being destroyed." According to him, the somnambulist " acts at the suggestion of circum- stances, and what seem most extraordinary in what he does are in reality instinctive reactions." This description agrees well with my view that in natural somnambulism the instincts of our pre-human ancestors are awakened, in- stincts which undej normal conditions are latent and rudi- mentary. Sometimes, under the stimulus of fear, the instinctive mechanism of swimming is awakened in man. It would be extremely interesting to know if a similar occurrence took place in somnambulists. I have been unable to find in 2o8 THE PROLONGATION OF LIFE literature any sufficient facts upon this subject. I caU quote only one case, and that with all reserve, which was published in the article " Somnambulism " in the Diction- naire des Sciences Medicates. "It is related that a som- nambulist who took to swimming during one of his fits was called by his name several times, and became so frightened when he awoke that he was drowned." It would be extremely interesting to collect more numerous facts on the instincts shown by somnambulists. I have given a good deal of attention to natural som- nambulism with the idea that I should find in it traits recalling those of the life of anthropoid apes. I think that the extremely varied phenomena of hysteria could supply us with other facts, useful in investigating the "psycho- physiological history of man. Perhaps some of the facts of so-called "lucidity" which are well established could be explained as the awakening of special sensations atro- phied in the human race, but present in animals. It is known that in vertebrate anatomy organs are found which have the structures of organs of "sense, but which are absent or quite rudirrientary in the human body. On the other hand, it is known that animals perceive some pheno- mena of the surrounding world, for the perception of which man has no organs of sense. Fish, for instance, appreciate gradations in the depth of water, birds and mammals have a sense of orientation and can anticipate changes in the weather more exactly than our meteorological science. When under the influence of hysteria, man may possibly be able to recover these senses of our remote ancestors, and to know things of which he is ignorant in the normal condition. Hysteria is common to man and animals. Amongst the numerous chimpanzees which I have owned, several have shown signs of hysteria. Some, when they were in the SOMNAMBULISM AND HYSTERIA 209 slightest degree annoyed, lay on the ground, screaming terribly, and rolling about like children in a fit of passion. One young chimpanzee used to pull out its hair when it was in a fit of temper. The view that hysteria is a relapse to the condition of our animal ancestors is supported by the conception of hysterical phenomena, suggested by Dr. Babinsky.^ This well-known neurologist thinks that "the phenomena of hysteria have, two special characters, the one being that they can be reproduced by suggestion in some cases with the most complete fidelity, and the other that they can disappear under the sole influence of persuasion." M. Babinsky thinks that "the hysteric patient is neither unconscious nor complet-ely conscious, but is in a state of special consciousness." In my opinion the latter con- dition corresponds to the state of mind of our more or less remote ancestors. Occasionally a man, under some sudden impulse, falls into a condition of extreme violence, and, being unable to control himself, commits acts of which he repents imme- diately afterwards. It is the custom to say that at such times the brute has awakened in the man. This is more than a metaphor. Probably some nervous mechanism from a remote ancestor has come into action, at the call of some stimulation. As our anthropoid ancestors and primitive man lived in tribes, it is natural that when men are grouped together, certain savage instincts should awaken. In this connection it is interesting to study the psychology of crowds. When man is surrounded by a great many of his fellows, he becomes particularly respon- sive to suggestion. This condition is characterised as follows by M. G. Le Bon,^ the author of a study on the ' Confdrence faite a la Societd de rintemat, June 28th, igo6. 2 The Crowd : a Study of the Popular Mind. English translation, London, 1896. P 2IO THE PROLONGATION OF LIFE psychology of crowds : " The most careful observations seem to prove that an individual immerged for some length of time in a crowd in action soon finds himself — either in consequence of the magnetic influence given out by the crowd, or from some other cause of which we are ignorant — in a special state, which much resembles the state of fascination in which the hypn6tised individual finds him- self in the hands of the hypnotiser. The activity of the brain being paralysed in the case of the hypnotised subject, the latter becomes the slave of all the unconscious activi- ties of his spinal cord, which the hypnotiser directs at will. The conscious personality has entirely vanished ; will and discernment are lost. All feelings and thoughts are bent in t^e direction determined by the hypnotiser" (p. n). Man, under the influence of the crowd, gets into a condi- tion like that of a hysterical patient and displays a state of mind identical with that of our ancestors. "Moreover, by the mere fact that he forms part of an organised crowd, a man descends several rungs in the ladder of civilisation. Isolated, he may be a cultivated individual ; in a crowd, he is a barbarian — that is, a creature acting by instinct" (P- 13)- It is quite natural to find relics of our prehistoric past in all kinds of hysterical phenomena. We could reach extremely interesting facts regapding the tribal and sexual life of apes, if we tried to compare with them the pheno- mena of human hysteria. The passionate gestures which are characteristic of some hysterical cases could probably be explained in this way quite simply, and the wild cries uttered by patients in acute hysteria would be similarly explicable. I think that just as anatomists seek for points of com- parison between man and animals, as palaeontologists make SOMNAMBULISM AND HYSTERIA an excavations to discover the buried remains of creatures intermediate between man and apes, so also, psychologists and doctors should investigate the rudimentary psycho- physical functions with the object of building up the history of the evolution of our psychical life. It cannot be doubted that in this branch of science new arguments would be found to support the already well founded theory of the simian origin of the human race. VS PART VI » SOME POINTS IN THE HISTORY OF SOCIAL ANIMALS I THE INDIVIDUAL AND THE RACE Problem of the species in the human race — Loss of indivi- duality in the associations of lower animals^Myxomycetes and Siphonophora — Individuality in Ascidians — Progress in the development of the individual living in a society In the following pages I shall try^to reply to the criticism on The Nature of Man that in that book I only considered the individual without thinking of the interests of society or of the race. I have been reproached for having lost sight of the truth that in the general course of evolu- tion the interests of the individual must yield to the higher interests of the community. It was asserted, in fact, that by advising orthobiosis, that is to say, the most complete cycle of human life, ending in extreme old age, I was suggesting something to the detriment of humanity as a ' whole. This objection rests on a misunderstanding which it will be interesting to clear up. I think that the complete development of the individual not only would not injure the community but would be of great advantage to it. More- over, we must not lose sight of the fact that the individual has rights which must not be ignored. THE INDIVIDUAL AND THE RACE 213 In the attack on my theory many facts were brought forward which show that in the animal and vegetable kingdoms the individual is always sacrificed to the advan- tage of the race. There is no doubt as to this, and in the course of this book I have given exact facts bearing on it. I instanced plants such as the Agave and some Crypto- gams which die as soon as they have reproduced; I have also spoken of the small female round worms (Nematoda) which are brutally torn in pieces and devoured by their progeny. It would be difficult to find better cases of the sacrifice of the individual to the species. The rule, how- ever, does not apply to nian, who, in this respect, stands in a special position. Since the arrival of man, several species of animals have disappeared from the earth. Man has played a large part in the destruction of the Moa (Aepyornis) of Madagascar, the largest member of the class of birds. He destroyed the Dodo of the Island of Mauritius and Steller's sea cow {Rhytina stelleri), a harmless relative of the Manatee, from the shores of the Aleutian Archipelago. Man is about to cause the extinction of several species of harmful carni- vorous animals, such as the wolf and the bear, and possibly it will not be long before automobiles have replaced the horse, which would then become extremely rare. How- ever, although he has destroyed so many other species, man has taken good care of himself. The progress already made by civilisation has considerably reduced our mor- tality. Every year, a large number of young infants are kept alive by the aid of hygiene and medicine. The de- crease of war and of assassination has also played a part in maintaining the race. The position which man has acquired in the world makes it more likely that what we have to fear is too great an increase of population, and 214 THE PROLONGATION OF LIFE although the theory of Malthus has not been verified in all its details, it is still true that man could multiply on the face of the earth too abundantly. It is already clear that almost in the proportion that humanity stops the effusion of its blood in war, it tends to limit the propaga- tion of the race. As the future of the species seems to be safe, it is natural to consider in the first place that of the individual. In this respect the facts of general biology are of special interest. Man is not the only social animal on the earth. Long before his appearance other living beings existed in or- ganised societies. The splendid colonies of Siphonophora float on the surface of the seas, whilst in the ocean depths there are societies of corals of extraordinary variability, whilst again, on land, many kinds of insects live in highly organised societies. This social life has been developed without external assistance, and without any code to regulate the conduct of the individuals united for a common purpose. It will be interesting to give a slight survey of the funda- mental principles of such societies ; I intend to draw special attention to one of the essential points in the societies of animals, hoping to elucidate the relations between the individuals and society. In the organisation of human society the most difficult points are the extent to which the society may encroach on the individual and the degree to which the individual may preserve his rights and his independency. Disputes on these have been interminable, and I do not propose to discuss the theories according to which an individual must be sacrificed for the good of the community to which he belongs. I shall limit myself to reviewing the fate of the individuals in societies of beings much inferior to man. THE INDIVIDUAL AND THE RACE 215 There are examples of societies coinposed of many in- dividuals, even amongst living things on the borderland between the animal and vegetable kingdoms. There may be found in woods, on dead leaves or on decaying timber, minute plants resembling tiny mush- rooms. These are Myxomycetes, and the visible portions are minute sacs filled with microscopical rounded bodies, known as spores. When one of the spores is moistened, there emerges a minute organism with a mobile appendage Fig. 21. — Isolated individuals of a Myxomycete. (After Zopff.) a, spore ; b—f, escape of the zoospores. Fio. 22. — Myxomycete indi- viduals united to form a Plas- modium. (After Zopff.) by which it can be impelled through water. A drop of water on a leaf or on a fragment of timber may be filled with numbers of these tiny swimming bodies (Fig. 21). Their free life as individuals, however, is of brief duration. When they come into contact, their bodies fuse, forming a gelatinous mass which may be quite large (Fig. 22). This mass is called a plasmodium, and is composed of a living substance which can move slowly over leaves and which exhibits streaming movements in the interior, so 2i6 THE PROLONGATION OF LIFE that the whole resembles in some respects the lava from a volcano. The Plasmodia may be regarded as societies in the con- stitution of which the individuality of the members has been completely sacrificed. The ideal of those philoso- phers who have urged that man should renounce his indi- viduality and merge himself in the community has been realised in the fullest way at the lower end of the scale of life, at an epoch inconceivably remote from the appear- ance of the human race. Amongst animals, eVen the most lowly, there are no societies in which the members are sacrificed so completely to the whole. Individuality is always preserved to a greater or lesser extent. Consider the polyps, colonies of which form reefs in.>the sea and may even become islands. These creatures live in aggregations, the mem- bers of which are incapable of living an independent life. They are united by living substance and resemble double monsters, such as Doodica and Radica, who were so much talked of some years ago when M. Doyen oper- ated upon them. The peritoneal cavities of these twins were in free communication, and the blood-vessels were united so that the blood of the one passed freely into the body of the other. In another double monster, the two Tscheck girls, Rosa and Josepha, the intestinal tracts communicate, both leading to a common rectum. In these, who are still alive, the peritoneum is joined and there is a single urethra. In the case of the coral polyps, the fusion of the indivi- duals of the colony is nearly always much more complete. Each individual has its own mouth and stomach, whilst the other organs cannot be assigned to individuals but must be regarded as common to the whole. THE INDIVIDUAL AND THE RACE 217 In the swimming polyps or Siplionophora, the loss of individuality is still more remarkable. These graceful and transparent creatures, sometimes large in size, live in the sea and may appear on its surface in great numbers. They possess many whip-like filaments provided with tentacles, swimming bells and stomachs. There can be no doubt as to their colonial nature (Fig. 23), but it is difidcult to decide as to whether each piece of the colony, each swimming bell, stomach and so forth, is to be regarded as an individual or an organ, different zoo- logists having taken different views on -the question. One interpretation is that colonial life has brought with it such modifications that of each in- dividual there remains only a single organ. Some individuals have been reduced to simple stomachs, attached to the central stem, whilst others have lost all organs except that of locomo- tion which has become one of the swimming bells of the colony. Other zoologists, and I myself amongst them, think that the Siphonophora are colonies of organs in which there has been as yet practically no development of individuality. A living chain of Siphonophora is simply a number of organs such as stomachs, tentacles, swimming bells and so forth, united on a common stem. I need not discuss the disputed point further, for the only matter pertinent to my argument is that in the Siphonophora the loss of individu- ality, the sacrifice of the parts to the whole, is not so great as in the Myxomycetes. Fig. 23. — One of the Siphonophora. (After Chun.) pn, pneumatic chamber ; clh, swimming bells; stl, stolon. 2i8 THE PROLONGATION OF LIFE In support of my view, I must recall the small forms of Siphonophora known as Eudoxia. These are detached pieces of the common trunk which swim freely in the sea and have a remarkable structure (Fig. V24). Their mobility is due to a bell provided with strong muscular fibres. The bell is a portion of an individual which pos- sesses organs of reproduction but which is devoid of the means to capture or digest food. These two functions are performed by a second individual which is closely united with the first. The nutrient individual has a long Fig. 25. — Botryllus colonies Fig. 2^.— Eudoxia. g^ mouth ; A, common (After Chun.) cloaca. tentacle by which the prey is captured, and a capacious stomach in which it is digested. The products of diges- tion pass by channels into the reproductive individual, carrying as it were a ready-made blood. Eudoxia in fact is a double being composed of an individual incapable of locomotion or of reproduction, but adapted for prehension and digestion, and of a second individual which can repro- duce and which is mobile. Eudoxia is an association resembling that of the blind man and the paralytic, in Florian's fable. Advance in the organisation of social animals is plainly THE INDIVIDUAL AND THE RACE 219 incompatible with complete loss of individuality, and this becomes the more apparent the higher we reach in the scale of life. In the social Ascidians, each member retains all the organs necessary to life. Animals of the genus Botryllus (Fig. 25), perhaps the most interesting of these Ascidians, occur in the form of circular colonies. The individuals which compose the colony are grouped radially around a common centre which is occupied by the cloaca. Each in- dividual has its own mouth and digestive tube, but the latter opens into a cloaca, common to all the individuals, by which the excreta are voided. There is, in fact, a single anus, as in the case of Rosa and Josepha whiqh I have just mentioned. II INSECT SOCIETIES Social life of insects — Development and preservation of individuality in colonies of insects — Division of labour and sacrifice of individuality in some insects Hitherto I have dealt with associations of animals the members of which are linked by an actual material bond. In the insect world there are many cases of highly devel- oped colonies. But the organisation of insects is high, and is incompatible with the existence of actual physical con- nection between the members of the society. In early stages of the development of the social instinct in bees, fully formed and similar individuals join together with the object of securing the safety of their individual lives. Sometimes they act together to drive away a common enemy, sometimes, as in winter, they cling in a mass to maintain their temperature. In such primitive societies, the young are not reared in common. It is only in much more highly developed colonies, such as those of some bees and wasps, and of ants and termites, that the chief object of the common action is care of the progeny. Such an extreme development of the colony is attained only by sacrificing the individuality of the members. There is a far-reaching division of labour, so that the queens, for instance, are mere machintes for laying eggs. In hive-bees INSECT SOCIETIES 221 the queen can no longer judge of what is good for the colony, her intellectual functions being degenerate. She is enclosed in her cell and supported by the workers, who see in her the future of the race. In times of want the worker-bees sacrifice their own lives and give the queen the last remnants of the food-supply so that she survives them. The males are incomplete individuals and are tolerated only, so long as they are required, after which the workers kill them remorselessly. The workers, which take such pains for the well-being of the hive, are incomplete individuals. Their brains are well developed and they are well equipped with organs for making wax and collecting food, but their reproductive organs are reduced to mere vestiges incapable of fulfilling their functions. Here then is a case of loss of individual characters in- creasing with the perfection of the colony. Amongst ants and termites, the social life of which arose quite indepen- dently of that of bees, the same course of events has been repeated. High intelligence and skill are confined to the workers, in which the reproductive organs are atrophied. The soldiers have powerful Jaws used in defence of the camp, but they, too, are sexually incomplete. The females and males, in which the reproductive organs have attained huge proportions so that the bodies are little more than sacs containing the sexual elements, have no intelligence and very little skill. An efxtremely curious specialisation, consisting in the formation of honey-bearing workers, occurs in some Mexi- can ants. Some of the workers of these races absorb so much honey that their bodies become swollen honey-bags. The limbs can no longer support the expanded body, and the insects, reduced to immobility, do not quit the burrows. 222 THE PROLONGATION OF LIFE Normal life has become impossible for these individuals, who soon die for the good of the community. When the normal workers or the sexual individuals are hungry, they approach the honey-bearers and take honey from their mouths. The honey-bearers have be- come no more than animated cupboards (Fig. 26). The termites belong to quite another Fig. 26.— a Honey- class of the group Insecta, but in their (After^Brehm ) ^^^^ ^ similar sacrifice of the individual to the state is practised. The females become transfortned to shapeless bags of eggs. They cannot move, but remain secluded in the recesses of the "ant "-hill, whei-e they lay as many as 80,000 eggs a day. The soldiers havfe become provided with jaws so enormous that these unsexfed insects can perform no function other than defence of the colony. The partial reduction of individuality in social insects never goes so far as in the cases of the lower animals I have described. It may be stated as a general rule that increase in the perfection of organisation brings with it a more or less complete preservation of individuality in the members of a community. I shall now Examine to what extent this law can be applied in the case of man. Ill SOCIETY AND THE INDIVIDUAL IN THE HUMAN RACE Human societies — Differentiation in the human race — Learned women — Habits of a bee, Halictus quadricinctus — CoUectivist theories— Criticisms by Herbert Spencer and Nietzsche — Progress of individuality in the societies of higher beings Social life is for the most part little developed amongst vertebrate animals. The birds and fishes which live in communities present no organisation of society even com- parable with that found amongst insects. There is little advance in this respect in the case of mammals, and it is not until we come to man that highly organised societies are to be found. Man is the first vertebrate tq develop an organ- ised social life. But, whilst in the insect world, instincts are of supreme importance in the regulation of the com- munity, there is little instinctive action in human com- munities. The consciousness of individuality, or egoism, is very powerful in human beings, and perhaps for that reason our ancestors made little progress in the development of social relations. Anthropoid apes adhere in little groups or in families without any true social organisation. Love of the neigh- bour, or altruism, appears to be a recent and feeble human acquisition. Although the organisation of human society is far ad- 224 THE PROLONGATION OF LIFE vanced and division of labour very complete, there is no differentiation of the individuals comparable with what is found amongst insects. Although in animals so different as Siphonophora, bees, wasps, and termites the develop- ment of the community, proceeding along different lines, has brought into existence non-sexual individyals, there is no trace of this specialisation amongst human beings. Certain abnormalities in the condition of the sexual organs are occasionally found in men and women, but these cannot be compared with the production of sexless individuals that has taken place amongst other social creatures. I cannot accept the view that we are to see something analogous to the case of worker bees in the prohibition of sexual relations imposed by some religious systems on a certain number of individuals. But in any event there is little importance in this occurrence, which is rapidly becoming rarer. In recent times, both in Europe and the United States of America, there has been an active development of a feminin- ist movement impelling women towards higher education. Women, no longer content with the avocations of mother and housewife, have pressed into professions such as law and medicine. There is a steady increase in the number of women who study at the Universities, and countries like Germany, which have tried to exclude women from higher studies, will soon have to yield before an irresistible pres- sure. Can we regard the results of this movement as analogous to the production of sexless workers which has taken place amongst social insects ? I think not. It is un- doubtedly true that a certain number of young women, who, for some reason or other are unlikely to marry, devote them- selves to scientific study. In these cases, however, celibacy is the cause, not the result of the increased intellectual SOCIETY AND THE INDIVIDUAL 225 activity. On the other hand, it must be remembered that many women students of science eventually marry. In St. Petersburg, for instance, there were 1,091 women in the Medical School ; of these 80 were already married and 19 were widows. Of the remaining 992, 436 or 44 per cent, married during the course of their studies. Observation of the femininist movement, which has lasted for more than forty years, shows that in most cases there is no tendency towards the formation of individuals re- sembling the infertile worker insects. Most lady doctors and learned women would like nothing better than to be the founders of a family. Even the women who have been most distinguished in the scientific world are no exception to the rule. In this relation it is very interesting to follow the details of the life of Sophie Kowalevsky, one of the most notable of learned women. In her youth, when she began to study mathematics, she would not admit that feel- ings of love had any importance. Later on, however, when she felt herself growing old, these sentiments awoke in her to such an extent that on the day when the prize of the Academy of Sciences was bestowed on her, she wrote to one of her friends, " I am getting innumerable letters of congratulation, but by the strange irony of fate, I have never felt so unhappy." The cause of this discontent reveals itself in the words which she addressed to her most intimate woman friend. "Why is it," she said, "that no one loves me? I could give more than most women, and while the most ordinary women are loved, as for me, I am not loved." ^ It is, in fact, impossible to regard the celibacy of personn devoted to religion or to scientific studies as the beginning of a special organisation analogous to that of worker bees. ' Souvenirs d'enfance de S. Kowalevsky, 1891;, pp. 301-31 1. Q 226 THE PROLONGATION OF LIFE However, it is still probable that in the human race a special differentiation has been established for the accom- plishment of different and essential functions. The organisation of human societies has certainly not fol- lowed the path by which social insects attained the forma- tion of sexless individuals. It much more closely re- sembles what has taken place in some isolated animal types. A solitary bee, named Halictus quadricinctus (Fig. 27), is characterised by the fact that the female does not die when she has laid her last eggs, as generally happens amongst insects, but remains alive to cherish her offspring. This final portion of her life does not last long, and the bee can- not play the prominent part of governess in a society of insects organised by this specialisation of elderly females. In the human race the individual life lasts longer and a division of labour takes place in the fashion suggested by Halictus quad- ricinctus. Fig. 2j.—BaHc/us An ordinary woman ceases to be fertile at (AfterBuffon.) between forty and fifty years old, that is to say, at a time when, according to statistics, she has still on the average twenty years to live. During this long period, she can perform an extremely useful function in society, a function resembling that of the old mothers of Halictus quadricinctus, and consisting chiefly in the bringing up and education of the children. Who does not know the extraordinary devotion of grand- mothers, and, as a general rule, of old women, who are extremely useful in bringing up children. And none the less, it must not be forgotten that, actually, old age begins too soon, that it is not what it ought to be under normal conditions, and that human life itself does not last nearly so long as it ought to do in ideal conditions. We may pre- SOCIETY AND THE INDIVIDUAL 227 did that when science occupies the preponderating place in human society that it ought to have, and when knowledge of hygiene is more advanced, human life will become much longer and the part of old people will become much more important than it is to-day. The members of human society are not divided into sexual and neuter individuals as amongst insects, but the active life of every individual can be divided into two periods, the first one of productive activity, and the second of sterility bift none the less devoted to work useful to the community. The essential difference between the two cases may be reduced to the contrast that whilst the individuals of which animal societies are composed are structurally in- complete, in human societies the individual preserves his integrity. We come, then, to the result that the more highly organised a social being may be, so also the more highly developed is his individuality. It follows that amongst the theories which seek to control social life, those are the best which leave a field sufficiently wide and free for the develop- ment of individual initiative. The ideal which has been so often advocated and according to which the individual is to be sacrificed as completely as possible to society, cannot be regarded as in harmony with the general law of organic associations. Special conditions exist in social life in which great sacrifices are inevitable, but such an arrangement cannot be considered as general and permanent. We may predict that the more human beings succeed in advancing communal life, the fewer cases there will be in which the individual has to be sacrificed. In the hope of subduing the egoism rooted in human nature, moralists have preached renunciation of individual happiness and the need of subordinating it to the good of Q 2 228 THE PROLONGATION OF LIFE the community. Very often such doctrine has borne little fruit, but there are cases where it has been embraced with such ardour that men and, still more, young women have been led to sacrifice their well-being for what they have taken to be the common good. However it may involve self-abnegation, there has been continued insistence on the duty of sacrificing the individual to the community. The existing great inequalities in the distribution of wealth have revived doctrines the object of which is to redress such injustice. For more than a century, different forms of socialism have claimed to formulate rules for the amelioration of mankind. They agree in a verdict against existing conditions, but follow different paths in their proposals for the reformation of society. The varieties of socialism are so numerous that it is difficult even to define the word. Although coUectivist theories have lost much of their early thoroughness, they are still far from admitting the just claims of the individuals con- stituting the society. At socialist assemblies and con- gresses the resolutions adopted frequently proclaim aggressively the sacrifice of the rights of the individual. The members of one socialist party have been seen refusing the collaboration of newspapers which are not the official organs of the party, or declining any co-operation with a government they have proscribed. In strikes organised by socialists, work is forbidden to men who ardently desire it. Recently printers have refused to set up newspapers the opinions of which they did not share, and even doctors have been known to decline to treat those belonging to another political party. It is no new charge against collectivists that they would encroach too much on individual liberty. They reply that " in social-democratic society of the future, tyranny and SOCIETY AND THE INDIVIDUAL 229 oppression will be impossible. The secret of the bond will reside in a discipline totally different from the inanimate obedience of the soldier, a discipline depending on a willing submission of the individual to the group because of the common object." ^ But such discipline and submission may go so far that the conscience of the individual is seri- ously offended. And so amongst the socialists themselves there has arisen a small group which declines to accept this submergence of the individual in the whole. This group is composed of anarchists, who, in the name of liberty and the individual, attack the property and sometimes the lives of their opponents. It appears that there has been a notable evolution of collectivist theories in the century or more in which the abolition of human misery has been an accepted problem. Whilst there was formerly advocated the total abolition of private property and the establishment of phalansteries for communal life, at the present time the demand is limited to the nationalisation of the means of production, leaving housing and food to be provided by individual property. Through a publication, of M. Kautsky, one of their best known representatives, the social democrats have announced that "the nationalisation of the land does not necessarily bring with it the abolition of private dwellings. The custom- ary attachment of the dwelling to agricultural employment will cease, but there is no reason why the peasants' houses should become collective property." "Modern socialism does not exclude individual property in food. One of the most important, perhaps the most important factor, in mak- ing human life happy and adding to its pleasures is the possible attainment of a private house. Collective owner- 1 W. Herzberg, Sozialdetnokratie und Anarchismus, 1906, p. 17. ^ Le problime agraire, 1905, p. 147. 230 THE PROLONGATION OF LIFE ship of the land does not exclude this." It is very difficult to separate house and garden, especially from the point of view of considering the pleasures of life. A garden fur- nishes the opportunity for endless improvements, many of which cannot be separated from the idea of individual pro- perty. The concessions which collectivists have been com- pelled to make show conclusively the importance of private property. Notwithstanding such modifications, many voices have been raised against the prospect of the socialisation of the means of production and the concomitant limitations of individual enterprise. The great English philosopher, Herbert Spencer,^ against whom narrowness of view or conservatism could be urged, energetically attacked collec- tivist doctrines as tending to reduce human individuality to a dead level. By a series of cogent instances, he showed the evil results of the best intentioned efforts to equalise opportunities and to abolish poverty. He foretold that slavery would be the real outcome if the State interfered too much in spheres that ought to be left to individual enter- prise. He believed that the institution of a coUectivist State would bring great dangers. Nietzsche has attacked socialism with his customary exaggeration. " Socialism," ^ he wrote, " is the fanatical younger brother of dying despotism, whose goods he wishes to inherit ; his efforts are, in the deepest sense of the word, reactionary. He wishes a wealth of power in the State greater than despotism ever enjoyed, but he goes 1 "The Coming Slavery" in Man versus the State, 1888, p. 18. ^ Human, too Human. French translation, 1899, pp. 405-407. A German critic has reproached me for my ignorance of Nietzsche's works. I have read several of them, but the mixture of genius and madness in them makes them difficult to use. In this connection Moebius' volume, ■ Ueber das Paihologische bei Nietzsche (Wiesbaden, 1902), is of interest. SOCIETY AND THE INDIVIDUAL 231 beyond all the past inasmuch as he strives absolutely to stifle the individual; for him the individual is a useless efflorescence of nature to be tamed into a useful organ of the community." Further, " Socialism at least teaches brutally and convincingly the danger of concentrating power in the State, for it is a covert attack on the State itself. When ks harsh voice raises the war-cry ' Let the State control as much as possible,' the cry will at first become louder ; but soon another phrase will grow equally clamant, ' Let the State control as little as possible.' " It is most probable that no shade of socialism will be able to solve the problem of social life with a sufficient respect for the maintenance of individual liberty. None the less the progress of human knowledge will inevitably bring about a great levelling of human fortunes. Intellectual culture will lead men to give up many things that are superfluous or even harmful, and that are still thought in- dispensable by most people. The conceptions that the greatest good fortune consists in the complete evolution of the normal cycle of human life and that this goal can be reached most easily by plain and sober habits will convince men of the folly of much of the luxury that now shortens human existence. Whilst the rich will choose a simpler mode of life and the poor will be able to live better, none the less, private property, acquired or inherited, may be main- tained. Evolution must be gradual and much effort and new knowledge is required. Sociology, a new-born science, must learn of biology, her older sister. Biology teaches us that in proportion that the organisation becomes more com- plex, the consciousness of individuality develops, until a point is reached at which individuality cannot be sacrificed to the community. Amongst low creatures such as Myxo- mycetes and Siphonophora, the individuals disappear 232 THE PROLONGATION OF LIFE wholly, or almost wholly in the community ; but the sacrifice is small, as in these creatures the consciousness of indi- viduality has not appeared. Social insects are in a stage intermediate between that of the lower animals and man. It is only, in man that the individual has definitely acquired consciousness, and for that reason a satisfactory social organisation cannot sacrifice it on pretext of the common good. To this conclusion the study of the social evolution of living beings leads me. It is plain that the study of human individuality is a necessary step in the organisation of the social life of human beings. PART VII PESSIMISM AND OPTIMISM I PREVALENCE OF PESSIMISM Oriental origin of pessimism — Pessimistic poets — Byron — Leopard! — Poushkin— Lermontoff — Pessimism and suicide In the attempt to formulate a pessimistic theory of human nature, we are naturally led to ask why it is that so many famous men have come to a purely pessimistic conception of human life. Pessimism, althoiigh it has been most prominent in modern times, is extremely old. Everyone knows the pessi- mistic wail of Ecclesiastes, written nearly ten centuries before our era : " Vanity of Vanities, all is vanity." Solomon, the supposed author, states that he " hated life, because the work that is wrought under the sun is grievous unto me, for all is vanity and vexation of spirit " (Eccl. ii., 17). Buddha raised pessimisim to the rank of a doctrine. All life seemed to him sorrow. "Birth is sorrow, old age is sorrow, disease is sorrow, union with one whom we do not love is sorrow, separation from one whom we love is sorrow, not to gratify desire is sorrow, in short, our five bonds with the things of the earth are sorrow."^ This Buddhistic ' Quoted by Oldenberg, Le Bouddka, French translation, Paris, '894, p. 214. 234 THE PROLONGATION OF LIFE pessimism has been the source of most of the modern pessimistic theories. Pessimism arose in the East and was much in vogue in India even apart from Buddhism. In the poems known under the name of Bhartrihari, and dating from the begin- ning of the Christian era, human Hfe has been commiserated in the following fashion. " One hundred years are the limit of the life of man ; night takes half of them, half of the other half is childhood and old age, the rest is filled with diseases, with separations and the misfortunes that come from them, with working for others and with wasting one's time. Where can happiness be found in an existence most like to the bubbles in broken water?" "Man's health is destroyed by every kind of care and disease. When fortune comes to him, evil follows as if by an open door. Death takes all human beings, one after the other, and they can offer no resistance to their fate. What is there assured amongst all that the mighty Brahma has created ? " ^ Pessimistic theories spread from the Asiatic East to Egypt and Europe. Three centuries before the Christian era, there arose the philosophy of Hegesias, which main- tained that experience was generally deceptive and that en- joyment was quickly followed by satiety and disgust. Ac- cording to him, the sum of pain surpassed the sum of pleasure in life, so that happiness was unattainable, and in reality never existed. It was vain to seek pleasure and hap- piness, as these could not be realised. It was better to try to be indifferent, dulling feeling and desire. In fact, life was no better than death, and it was often preferable to end it by suicide. Hegesias was called Pisithanatos, the adviser of death. " Listeners thronged around him, his doctrine spread rapidly, and his disciples', persuaided by his voice, ' P. Rdgnaud, " Le pessimisme brahmanique," in Annales du Musie nimet, 1880, vol. i, pp. iio-ili. PREVALENCE OF PESSIMISM 235 gave themselves to death. Ptolemy was perturbed by it, and fearing that the dislike of life would become contagious, closed the school of Hegesias and exiled its master."^ The pessimistic tendency sometimes appears in the writ- ings of many Greek and Latin philosophers and poets. Seneca wrote : " The spectacle of human life is lamentable. New misfortunes overwhelm you before you have freed vourself from the old ones."^ It is in modern days, however, that there has been the greatest spread of pessimism. Besides the philosophical theories of the last century, those of Schopenhauer, von Hartmann and Mailaender, which I discussed sufficiently in The Nature of Man, poets have formulated a pessimistic view of life. Even Voltaire was a pessimist in the following lines : Alas I what are the course and the goal of life? Only follies and then the darkness. Oh Jupiter ! in creating us you made A heartless jest. In The Nature of Man I described Byron's expression of his conception of the evils of human life. Soon after the death of the great English poet, a celebrated Italian poet, Giacomo Leopardi, sounded a note of abandoned pessim- ism. Here are words which he addressed to his own heart': "Be quiet for ever, you have beaten enough, nothing is worthy of your beating and the earth is not worthy of your sighs. Life is nothing but bitterness and weariness, there is nothing else in it. The world is nothing but mire. Repose from now onwards. Be in despair for ever. Destiny has given us nothing but death. Despise henceforth your- ' Guyau, La Morale d Epicure, 4th edition, 1904, p. 116. * Ad Marciam, chap. x. * Poesies et ceuvres morales, by Leopardi. Ti:anslated into French 1880, p. 49. 2.36 THE PROLONGATION OF LIFE self and nature, and the shameful concealed power which decrees the ruin of all and the infinite variety of all." Leopardi makes his readers witnesses of his distraction and his grief: " I shall study the blind truth " — he wrote in a poem dedicated to Charles P^poli — " I shall study the blind fates of things mortal and immortal. Why humanity came into existence, and was burdened with pain and sorrow, to what final end destiny and nature are driving it, i for whose pleasure or advantage is our great pain, what order, what laws rule this mysterious universe which wise men cover with praise, and I am content to wonder at" (ibid., p. 15). Quite a school of poets has been developed, singing the pain of the world, the " Weltschmerz " of German authors, amongst whom Heine and Nicolas Lenau are specially distinguished. Russian poetry was born under the influence of Byron- ism, and its best exponents, Poushkin and LermontofF, often laboured over the problem of the object of human existence, finding only sad answers. Poushkin, who is justly regarded as the father of lyric poetry in Russia, stated his pessimistic conception in the following lines : — Useless gift, gift of chance, Life, why wert thou given me? And why from the beginning art thou doomed Irrevocably to death? What unfriendly power Has drawn me from the darkness, Has filled my soul with passion, And breathed doubt into my soul? There is no goal for me, My heart and riiy soul are empty; And the dull emotion of life Has filled me with black care. PREVALENCE OF PESSIMISM 237 Recently, Mde. Ackermann, in a series of short poems, has given voice to the grief caused to her by the world and life as they are, although she does not state exactly the reason of her bitter complaints. Whilst pessimistic philosophers and poets reflect the thoughts and feelings of their contemporaries, it is certain that they also seriously influence their readers. And so there has come into existence a deeply rooted conviction that the miseries of human life are far from being counter- vailed by its happiness. Probably such ideas have influ- enced the number of suicides. We do not know with any certainty the real motives of most cases of self-destruction, but it cannot be denied that the trend of modern thought has played an important part. According to statistics, the chief causes of suicide are "hypochondria, melancholia, wearinessof life, and unbalancing of the mind." Thus from the Danish statistics it appears (and Denmark is the country in which suicide is most prevalent) that of 1,000 cases of suicides of males, between 1866 and 1895, 224, or one- quarter, were referred to the causes I have just mentioned. In the case of women, the corresponding figures are higher, amounting to nearly one-half (403 out of 1,000). The second most common cause of male suicides is alcoholism (164 in 1,000).' It is very probable that pessimism was the determining condition in most of the suicides referred to these two categories of causes. Leaving out of the question the true cases of mental alienation, amongst the victims of melancholia, hypochondria and weariness of life, in whom the mental condition was not pathological in the strict sense of the word, there must have been many who killed them- selves because their view of life was pessimistic. And amongst the victims of drink, there are many who take to ^ These facts are taken from Westergaard, 2nd edit., 1901, p. 649. 238 THE PROLONGATION OF LIFE alcohol because they are convinced that life is not worth preserving. The progressive increase in the numbers of suicides in modern times is an index of the great influence of pessi- mism. There have been even societies for the promotion of suicide. In such a society, founded in Paris in the begin- ning of last century, members placed their names in an urn, to be drawn by chance. He whose name was drawn had to kill himself in the presence of the other members. According to its rules, this society admitted only persons of honour who must have had experience of "the injustice of man, the ingratitude of a friend, the infidelity of a wife or mistress, and who, moreover, for many years had had a void in their souls and a distaste of what this world can offer."! Although such societies no longer exist, individuals con- tinue to put their lives to an end, in greater numbers every year. * Dieudonnd, Archiv fur Kulturgeschichte, 1903, vol. i, p, 357. II ANALYSIS OF PESSIMISM Attempts to assign reasons for the pessimistic conception of life — Views of E. von Hartmann — Analysis of Kowalevsky's work on the Psychology of Pessimism In view of the facts I brought together in my last chapter, there is occasion to inquire if it be possible to discover the intimate mechanism by which men arrive at a conception of life as an evil to be got rid of as quickly as possible. Why do so many think that man is less happy than the beasts, and that cultured and intelligent men are more unhappy than those who are ignorant or feeble-minded ? I have related how in a society of friends of suicide, injustice and unfaithfulness were regarded as prime factors in arousing a distaste for life. Shakspeare made Hamlet exclaim that if it were possible to put an end to our days no one would continue to live : — For who would bear the whips and scorns of time, The oppressor's wrong, the proud man's contumely? For Byron, besides diseases, death and slavery, the evils that we see, there are others: — And worse, the woes we see not — which throb through The immedicable soul, with heart-aches ever new. In many of his works he insists on the feeling of satiety 240 THE PROLONGATION OF LIFE which was almost continually upon him. Every sensation of pleasure that came to him was rapidly succeeded by a still stronger feeling of disgust. Heine thought that existence was evil and saw .... across the hard surfaces of the rocks The homes of men and the hearts of men — In the one as in the others, lies, imposture and misery. As I urged in The Nature of Man, consciousness of the shortness of human life has been an important factor in exciting pessimism, and we find this theme recurring in pessimistic writers. Leopardi returns to it again and again in his poems. " Falling in peril of death from some mys- terious disease," he said in his Souvenirs, "I lamented over my sweet youth and the flower of my poor days which was to fall so soon, and often in the midnight hours wove from my sorrows, by the pale light of my lamp, a sad poem, and in the silence of the night wept over my fleeting life, and half fainting, sang to myself my funeral song " {loc. cit., p. 28). The bas-relief on an ancient tomb, represent- ing the departure of a young girl who took farewell of her friends, suggested to Leopardi the following thoughts : " Mother, who from their birth makes her family of living beings tremble and weep. Nature, monster unworthy of our praise, who brings into the world and nurtures only to kill, if the premature death of a mortal be evil, why do you bring it on so many innocent heads? If it be a good, why do you make it sad for those who go and for those left behind? Why is it the hardest grief to console? The only relief from our woes is death, death, the inevitable end, the immu- table law which you have established for human beings. Why, alas, after the sad voyage of life, do you not make the arrival joyful ? This certain end, this end which is in our souls all our lives, which alone can soothe our troubles, ANALYSIS OF PESSIMISM 241 why do you drape it in black and surround it with mournful shades ? Why do you make the harbour more terrible than the open seas?" (loc. cit., p. 55). The three chief grievances — injustice, disease, and death — often come together. From the anthropomorphic point of view fate is represented as a sort of wicked being who commits injustice by visiting all kinds of evils on mankind. A pessimistic conception of life is arrived at by a complex psychological process in which both feelings and reflection are involved, and hence it is difficult to analyse it satisfac- torily. Formerly, therefore, writers were content with general and very vague estimates of the process by which we may become pessimists. Ed. von Hai-tmann has tried to deal more exactly with this inner process of the human mind. In the first place, he lays stress on the fact that pleasures always bring less satisfaction than pains bring grief. False notes in music, for instance, are more painful than the best music is delightful. The pain of toothache is much more violent than the pleasure when relief comes. So also with all diseases. In love, according to Hartmann, the pleasure is always very greatly over-balanced by the pain. Muscular work brings pleasure only in a very small degree, and devotion to science and art and intellectual work in general brings more pain than pleasure to the votaries. As the result of an analysis, Hartmann is con- vinced that there is much more pain than pleasure in the world. Pessimism is founded upon the essential nature of human feelings. M. Kowalevsky,* a German philosopher at Koenigsberg, adopting the modern habit of measuring mental processes as exactly as possible, has recently published an attempt ' Kowalevsky, Studien zur Psychologie des Pessimistnus, Wiesbaden 1904 R 242 THE PROLONGATION OF LIFE to analyse pessimism psychologically. Although this has not solved the problem, it is extremely interesting as an instance of the application of the methods now being adopted in modern psychology. M. Kowalevsky took advantage of all the known methods of estimating the relative values of our emotions; he tried to make use of the notes of Munsterberg, another living psychologist who kept a journal in which he set down daily his psychical and psyclio-physical impressions. The object of the work had no relation to the question of pessimism, and for that reason Kowalevsky thought that it was speci- ally important in his investigations. Munsterberg was not content with the existing classifica- tion of emotions as agreeable or painful. He subdivided them much further. He recognised, for instance, emotions of tranquillity and excitement, serious and pleasant impres- sions. Having completed the reckoning, Kowalevsky came to the conclusion that his colleague, who was by no means a pessimist, but a psychologist of well-balanced mind, experienced many more painful emotions (about 60 per cent, as compared with 40 per cent.) than agreeable emotions. " Such a result is in favour of pessimism," con- cluded Kowalevsky. However, he went beyond the foregoing enquiry. By several other methods, he tried to gain an exact idea of the value of our emotions. He visited elementary schools in order to investigate the pleasures and pains of the scholars. In the case of 104 boys, of eleven to thirteen years of age, he found that pain was much more deeply felt than corre- sponding pleasure. Thus, while in 88 cases illness was set down as an evil, only in 21 was health reckoned as a good. One-third of the pupils noted down war amongst evils, whilst only one noted peace amongst the good things. ANALYSIS OF PESSIMISM 243 Poverty was written down thirteen times as an evil, against twice in which riches were put down as a good. In another series of investigations, Kowalevsky took notes on the pleasures and pains felt by pupils of the two sexes attend- ing the same school. The result was that the greatest evil, according to them, was illness, noted 43 times, then death 42 times, after which came fire 37 times, hunger 23 times, floods 20 times. Amongst the good things, the first place was given, as might have been expected, to games (30) and the second to presents. As Kowalevsky did not find that such investigations could solve the problem, he tried to discover a more exact method. With this object, he turned to different sensa- tions, such as those of smell, hearing and taste, to which he applied methods of exact measurement. In the case of taste, for instance, he determined the minimum quantity of different substances which could excite definitely plea- sant or unpleasant sensations. In his experiments, Kowal- evsky found that doses which gave bad tastes were not balanced by those which gave good tastes. For instance, to neutralise the unpleasant taste of quinine, it was neces- sary to employ a much larger quantity of sugar. He was specially pleased with one experiment. Four persons were given definite mixtures of sugar and quinine in order to discover the proportion of the two substances necessary to obtain a neutral sensation. He found that to take away the bad taste of quinine, it was necessary to double the quantity of sugar given. Similarly with smells, he found that those which were unpleasant were appreciated much more strongly than those which were pleasant. Here, then, was a series of scientific results supporting the view of the pessimists. Must we really conclude from them that the world is very badly arranged? The analysis of R 2 244 THE PROLONGATION OF LIFE " good and bad temper made by Kowalevsky is in favour of sucii an interpretation. In order to estimate these con- ditions of mind, he measured the gait, that is to say, the number of steps talcen in a minute. This method depended upon the following idea. It is an accepted view that the condition of mind is shown by the rapidity of the human walk ; we have only to compare the slow pace of a man in deep grief with the rapid steps of a man in a state of joy. Pain, as a general rule, depresses, while joy stimulates voluntary movements. The result of the measurements taken according to this method give a new argument in favour of pessimism. However, it is useless to attempt to analyse these figures on which Kowalevsky had to em- ploy the integral calculus, because the principle of his method cannot be supported. As a matter of fact, the rapidity of walking is an index of the degree of excitation, and not of the happy or unhappy condition of the mind. When a person suddenly undergoes a strong impression, either pleasant or unpleasant, he takes to walking actively about in his room, and may even want to go out of doors to walk more quickly. A letter which has been received and which gives some unexpected news, as for instance of the infidelity of a person one loves, or of an inheritance which one did not expect, produces a condition of excite- ment shown chiefly by rapid walking. Many orators and professors have to make gestures and to walk about in the course of their lectures. A man of science to whom some new idea comes and who wishes to think it out, rises from his chair and begins to walk. But not only on such pleasant occasions, but when one has to face an insult or an act of defiance which makes one very angry, the need to walk actively is felt. It is therefore impossible to utilise records of movements in the study of the pessimistic state of mind. ANALYSIS OF PESSIMISM 245 M. Kowalevsky employed still another mode of attack- ing the problem. He examined the recollection of painful or pleasant impressions. He asked the children of both sexes, whom he was investigating, questions which gave him indications as to whether pleasures or pains made the more lasting impression on the memory, and he registered the answers. The result, which agreed with what had already been obtained by Mr. Colegrove, an American psychologist, was unfavourable to the pessimistic view. He found, in fact, that in the majority of cases (70 per cent.) recollection of pleasant impressions predominated. However, in such investigations there is a facile source of error arising from the condition of mind of those who are being questioned. It is probable that Kowalevsky made his enquiry in school during recreation time, when most of the pupils were free from the boredom of the actual class. When we are happy the tendency exists* in us to recall pleasant impressions of the past. If the enquiry had been made during a difficult or wearying lesson, or on children shut up in a hospital, or undergoing punishment, it is probable that the result would have been reversed. It is evident that all such attempts to solve a problem so complex as that of pessimism, even by the so-called exact methods of physiological psychology, cannot lead to any convincing result. Thus Kowalevsky's different in- vestigations led to contradictory conclusions. Whilst some of his series of facts supported the pessimistic conception, others were opposed to it, and he obtained no definite general conclusion. How can one expect to apply a method of measurement to sensations and emotions so different, not only from the qualitative point of view, but also in relation to their intensity ? Take, for instance, the case of an individual who has experienced in one day nine sensations which were painful and one which was 246 THE PROLONGATION OF LIFE agreeable. According to the valuation of experimental psychologists, he ought to have reason to become a pessi- mist. However, this may be far from the case, if the nine painful impressions were much weaker than the single happy impression. The first were provoked by small wounds to his pride, fleeting p^ins of no importance, and small losses of money, whilst the happy emotion came from receiving a love letter. The sum of the ten impressions would be a happy one, and might well put him in an opti- mistic frame of mind. The learned attempts of experimental psychologists must be abandoned, as incapable of illuminar ting the problem. If, however, the human spirit still seeks some means of explaining the psychology of pessimism, there remains only the less subtle method given by the bio- graphical study of human beings. Ill PESSIMISM IN ITS RELATION TO HEALTH AND AGE Relation between pessimism and the state of the health — History of a man of science who was pessimistic when young, and who became, an optimist in old age— Optimism of Schopenhauer when old — Development of the sense of life — Development of the senses in blind people — The sense of obstacles Animals and children in good healtii are generally cheerful and of optimistic temperament. As soon as they fall ill they become sad and melancholy until their recovery. We may infer from this that an optimistic view is correlated with normal healthy whilst pessimism arises from some physical or mental disease. And so in the case of the prophets of pessimism, we may seek for the origin of their views in some affliction. The pessimism of Byron has been attributed to his club-foot, and that of Leopardi to tuberculosis, these two nineteenth century exponents of pes- simism having died whilst young. Buddha and Schopen- hauer, on the other hand, reached old age, whilst Hart- mann died when sixty-four years old. Their diseases at the time when they formed their theories could not have been very dangerous, and none the less they took a most gloomy view of human existence. The recent historical investiga- tions of Dr. Iwan Bloch^ make it very probable that Schopenhauer, in his youth, contracted syphilis. There ' Medicinische Klinik, 1906, n. 25 and 26. 248 THE PROLONGATION OF LIFE has been found a note-book of the great philosopher in which he wrote down the details of the severe mercurial treatment which he had to undergo. The disease, how- ever, was not contracted until several years after the appear- ance of his great pessimistic work. Although we must attach due weight to the connection between disease and pessimism, we can assure ourselves that the problem is more complex than it appears at first sight. It is well known that blind people often enjoy a constant good humour, and, amongst the apostles of op- timism, there has been the philosopher Duering,^ who lost his sight during his youth. Moreover, it has been noticed that persons affected with chronic diseases frequently have a very optimistic concep- tion of life, whilst young people in full strength may become sad, melancholic, and abandoned to the most ex- treme pessimism. Such a contrast has been well described by Emile Zola in his novel La Joie, de Vivre, where a rheumatic old man, tried by severe attacks of gout, main- tained his good humour, whilst his young son, although vigorous and in good health, professed extreme pessi- mism. I have a cousin who lost his sight in early youth. When he grew up he formed a most enviable judgment of life. He lived in his imagination and everything in life seemed to him good and beautiful ; he married, and pictured his wife to himself as the most beautiful woman in the world, and thus he feared nothing more than the recovery of his sight. He had adapted himself to live without sight, and was con- vinced that the reality was much lower than his imagina- tion. He feared that if he were able to see his wife she would appear to him less beautiful. 1 Ber IVerth des Lebens. PESSIMISM AND HEALTH AND AGE 249 I know a girl twenty-six years old, blind from her birth, the subject of infantile paralysis and liable to fits of epilepsy. She is nearly an idiot, lives in a carriage, and sees life from its best side. She is certainly the most happy member of all her family. The good humour and megalomania of those affected with general paralysis of the insane also is well known. All such examples show that pessimism cannot be explained as depending on bad health. Examination of the state of mind of a pessimist may throw some light on the subject. There has been within my own circle a typical case of a person who went through a phase of life in which everything seemed as gloomy as possible. My intimate knowledge of him makes it possible to apply my observations to the matter under discussion. The subject was born of parents of good health and in comfortable circumstances, so that, from the beginning of . his life, he was surrounded by a favourite environment. Me lived in the country and escaped the diseases of childhood, so that he reached maturity in good health, and passed well through college and the university. Science attracted him, and he had the ambition to become a distinguished investi- gator. He threw himself into a scientific career with zeal and ability. His ardent disposition, although certainly favourable to work, was the cause of many troubles. He wished to succeed too quickly, and the obstacles he encoun- tered embittered him. As he thought himself naturally talented, he conceived it to be the duty of his seniors to aid his development. And so, when he met with natural and very common indifference from those who had already be- come successful, the young man thought that there was a plot against him, to bring to nothing his scientific talents. From this view, many quarrels and difficulties arose, and as 250 THE PROLONGATION OF LIFE he could not overcome these sufficiently quickly, he tell into a mood of pessimism. In this life, he said to himself, the main thing is to adapt oneself to external conditions. According to Darwin's law of natural selection, the indivi- duals who do not succeed in adapting themselves go to the wall. The survivors are not the best but only the most cunning. In the history of the earth it has been seen that many lower animals have long survived creatures much higher in organisation and general evolution. Whilst so many of the higher mammals, the nearest relatives of man, have been crushed out of existence, simpler animals, such as evil-smelling cockroaches, have survived from the re- motest times, and multiply in the neighbourhood of man in despite of his efforts to exterminate them. The animal series and human evolution itself show that delicacy of the nervous system, with its concomitant extreme development of the sensibilities, hinders the power of adaptation and brings with it insuperable evils. The least blow to his pride, or a slighting word from a comrade, threw this pessimist into a most painful condition. No, he would cry, it would be better to be without friends, if one is to be wounded so deeply by them. It would be best to seclude oneself in some remote spot and be engrossed in one's work. He was very impressionable and a lover of music, and from his visits to the opera, he retained in his mind an air from the " Flute enchantee." " Were I as small as a snail, I would hide myself in my shell." His moral hypersensibility was associated with physical hyperassthesia. Noises of all kinds, such as the whistling of railway-trains, the cries of street-vendors, or the barking of dogs, excited extremely painful sensations. The least trace of light prevented him from sleeping at night. The unpleasant flavour of most drugs made it impossible for him to take medicine. He PESSIMISM AND HEALTH AND AGE 25-1 agreed thoroughly with the pessimistic philosophers who declare that the ills of life far surpass the good things. He required no experiments on the sense of taste to convince him. He believed that the organisation of his body pre- vented him from becoming adapted to external conditions and that he would have to disappear like the mammoth and the anthropoid apes. The course of his life confirmed the convictions of our pessimist. He had no private fortune and married a woman who became affected with tuberculosis, and so was con- fronted with the greatest evils of existence. A young lady, hitherto in good health, contracted influenza in some northern town. It was a mere nothing, said the doctors; influenza is everywhere and no one escapes it ; after a little patience and rest, she will be well again. However the "influenza" persisted and brought with it feebleness and wasting. The doctors then found that there was a little dullness in the apex of the left lung, but as there was no bad family history, there was nothing to fear. I need not describe the familiar course of events. The trifling influ- enza was replaced by degeneration of the left lung, and brought death after four years of great suffering. Towards the end, when there was no hope, the patient found her only solace in morphine. Under the influence of that drug, she passed hours free from pain and in relative calm, but her excited imagination passed almost into hallucination. It is not surprising that the death of his wife was a severe shock to the husband. His pessimism became complete. He was a widower at the age of twenty-eight years, and, in his condition of mental and physical exhaustion, took to morphine like his wife. He knew that it was a poison which would complete the ruin of his constitution and make his work impossible. But what was the value of his life ? As ;i52 THE PROLONGATION OF LIFE his organisation was too nervous for him to adapt himself lo external conditions, was it not as well to come to the aid of natural selection and so make room for others ? As it hap- pened, a large dose of morphia did not solve the problem. It produced in him a condition of extraordinary happiness combined with extreme physical weakness. Little by little the instinct of life awoke in him, and'he resumed his work. Pessimism, however, remained the fundamental quality in his character. Life was not worth the pains necessary to protect it. It would be a true crime to bring into the world other living beings doomed to elimination by natural selec- tion. Moral and physical sensibility, as they continued to develop, brought with them so much evil that there could be no good end. The "injustice" of those \yho were un- willing to " understand " him made life painful to the man himself and to those about him. The closest absorption and hard work made his existence more tolerable, but his pessimistic conception was not in the least altered. Thus, he was easily driven to morphia for consolation, when he suffered from some act of "injustice" or vexation. A severe fit of poisoning, however, stopped this excess. Years passed. When he discussed with his friends the problem of the goal of human life and similar topics, he was always ardent in supporting the point of view of pes- simism. However, he occasionally wondered if his pleading for this were really sincere. As his nature was honest and frank, this question which he put to his conscience appeared most curious to him. Analysis of what passed in his mind revealed to him a change. It was not that his conceptions had changed in the course of years, but rather his feelings and sensations. As he was now in full maturity, between forty-five and fifty years old, he found that there was a great change in the intensity of these last. Disagreeable sounds PESSIMISM AND HEALTH AND AGE 253 did not trouble hini to the same extent as formerly, and he was undisturbed by the caterwauling of cats or by harsh street cries. As his hypersensibility diminished his character became more tolerant. Even the injustices or wounds to his pride which formerly drove him to mor- phia, no longer provoked in him any painful reaction. He could easily conceal the bad effect of these upon him, and no longer felt them with the same intensity. Thus his character had become much more supportable to those with him, and much better balanced, " It is old age which is come upon me," he cried ; " I feel painful impressions much less acutely and pleasant impres- sions have less effect on me. The relative proportions of the two remain as before, that is to say, unpleasant things still impress me much more strongly than pleasant things." By analysing and comparing his emotions, he discovered some- thing new, in fact that some impressions were, so to speak, neutral. As he was less sensitive to unharmonious sounds, and at the same time less affected by music itself, he found himself in a more tranquil condition. Awakening in the middle of the night, he experienced a kind of happiness which reminded him of that formerly produced by mor- phine, and which was characterised by his hearing no sound, either pleasant or unpleasant. He became less disgusted by drugs, but at the same time indifferent to the pleasures of the table which he had appreciated in his youth. He also delighted in consuming more and more simple food. A piece of black bread and a glass of water became real treats to him. Insipid dishes, which he formerly despised, were now specially agreeable to him. Just as in the evolution of art, violent coloration has yielded to the low tones of Puvisde Chavannes, as views of fields and meadows are preferred to those of mountains and 254 THE PROLONGATION OF LIFE lakes ; just as in literature, tragic and romantic studies have been successfully replaced by scenes of daily life, so the ' psychical development of my friend displayed a similar change. Instead of taking his pleasure in mountains or in places famed for their picturesqueness, he was content to watch the budding of the leaves of the trees of his garden, or a snail overcoming its fears and putting out its horns. The simplest occurrences, such as the lisping or the smile of a baby or the first words of a child, became sources of real delight to this elderly man of science. What was the meaning of these changes which took so many years to be accomplished ? It was the growth of his sense of life. The instinct of life is little developed in youth." Just as a young woman gets more pain than pleasure from the earlier part of her married life, just as a new-born baby cries, so the impressions from life, especially when they are very keenly felt, bring more pain than pleasure during a long period of human life. The sensations and feelings are not stable; they undergo evolution, and when that takes place more or less normally, it brings about a state of psychical equilibrium. And thus my friend, formerly so entrenched in pessimism, came to share my optimistic view of life. The discussions that we had had for so many years ended in complete agree- ment. " However," said he, " to understand the value of life, one must have lived long ; otherwise one is in the posi- tion of a man blind from his birth to whom are recounted the beauties of colours." In a word, my friend towards the end of his life changed from abject pessimism to complete optimism. Such a transformation, or evolution cannot be regarded as unusual. In The Nature of Man, I showed that most of the great pessimistic writers had been young men. PESSIMISM AND HEALTH AND AGE 255 Such were Buddha, Byron, Leopardi, Schopenhauer, Hart- mann, and Mailaender, and there might be added many other names of less well known men. The question has ofte^ been asked why Schopenhauer, who was certainly sincere in his philosophy and who ex- tolled Nirvana as the perfect state, came to have a strong attachment to life, instead of putting it to a premature end as was done later on by Mailaender. The reason was that the philosopher of Frankfort lived long enough to acquire a strong instinct of life. M. Moebius," a well-known autho- rity on madness, has made a close investigation of Schopen- hauer's biography, and has established the fact that towards the end of his life his views were tinged with optimistic colours. On his seventieth anniversary, he took pleasure in the consoling idea of the Hindoo Oupanischad and of Flourens that the span of man's life might reach a century. As Moebius put it, " Schopenhauer as an old man enjoyed life and was no longer a pessimist" (p. 94). Not long before his death he still hoped to survive yet another twenty years. It is true that Schopenhauer never recanted his early pessimistic writings, but that was probably because he did not fully realise his own mental evolution. In looking through the work of modern psychologists, I cannot find recognition of the cycle of evolution of the human mind. In Kowalevsky's able and conscientious study of pessimism, I was specially struck by one phrase. " Evils such as hunger, disease, and death are equally ter- rible at all stages of life and in every rank of society" (p. 95) said that author. I notice here a failure to recog- nise the modification of the emotions in the course of life which, none the less, is one of the great facts of human ' U*btr Schopenhauer, Leipzig, 1899. 256 THE PROLONGATION OF LIFE nature. Fear of death is by no means equally great at all stages of life. A child is ignorant of death and has no conscious aversion from it. The youth and the young man know that death is a terrible thing, but they have not the horror of it that comes to a mature man in whom the instinct of life has become fully developed. And we see that young men are careless of the laws of hygiene, whilst old men devote to them sedulous attention. This differ- ence is probably a notable cause of pessimism in young men. In his studies of the mind, Moebius ^ has stated his view that pessimism is a phase of youth which is succeeded by a serener spirit. " One may remain a pessimist in theory," he says, " but actually to be one, it is necessary to be young. As years increase, a man clings more firmly to life." " When an old man is free from melancholia, he is not a pessimist at heart." "We cannot yet explain clearly the psychology of the pessimism of the young, but at least we can lay down the proposition that it is a disease of youth" (p. 182). The cases of Schopenhauer and of the man of science whose psychical history I have sketched fully confirm the view of the alienist of Leipzig. The conception that there is an evolution of the instinct of life in the course of the development of a human being is the true foundation of optimistic philosophy. It is so important that it should l ; examined with the minutest care. ' Our senses are capable of great cultivation. Artists develop the sense of colour far beyond the point attained by ordinary men, and distinguish shades that others do not notice. Hearing, taste, and smell also can be educated. Wine tasters have an appreciation of wine much more acute than that of other men. A friend of mine, who does not * Moebius, Goethe, vol. i, Leipzig, 1903. PESSIMISM AND HEALTH AND AGE 257 drink wine, can distinguish burgundy from claret only by the shapes of the bottles, but is devoted to tea and has a very fine palate for different blends. I do not know if a good palate is a natural gift, but however this may be, it is certain that the palate can be brought to a high condition of perfection. The development of the senses is specially notable in the case of the blind in whom other powers become ex- tremely acute. As I thought that investigation of the educability of other senses in blind persons very important from the point of view of the development of the sense of life, I have tried to obtain the best available information on the question. The perfection of touch in the blind is accepted so generally as a truth that one would have ex- pected to find convincing facts in its favour. However, it is not true. Griesbach,' using a well-known method for estimating tactile discrimination, found that the sense of touch is not more acute in the blind than in normal persons. Blind persons distinguished the points of a pair of com- passes as separate, only when they were at least as far apart as in case of normal persons. Dr. Javal,^ a well-known oculist who himself became blind, stated his surprise at find- ing that "tactile discrimination is quite notably less acute in thecase of the blind than in the case of those with unimpaired vision. For instance, the index finger of a blind man who was a great reader got separate sensations from the points of a pair of compasses only when these were three milli- metres apart, whilst a man with normal sight had the double sensation at a distance of two millimetres " (p. 123). Griesbach goes still farther, stating that neither hearing * V. Kunz, " Zur Blindenphysiologie," Wiener medicin. Wochenschrift, 1902, No. 21. ^ Physiologie de la Lecture et de t£criture, Paris, 1905. 258 THE PROLONGATION OF LIFE nor smell is better developed in the blind than amongst normal people. Although these senses may come to re- place to a certain extent the sense of sight, this occurs merely because the blind person uses impressions which the clear-sighted person hardly notices. As we see what is going on around us, we do not concentrate our attention on the different sounds and smells or other such pheno- mena. The blind person, on the other hand, not being absorbed by impressions of sight, gives attention to the others. Such and such a sound tells him that the garden gate of his neighbour has been opened to let out a carriage which he must avoid. A particular smell lets him recog- nise the place where he is, as stable or kitchen. From the present point of view, it is not exactly the acuteness of the senses which is most important. The acuteness might be equal in a blind person and in a normal person. It might even be greater in the latter^ and yet it is only the blind person who can decipher without difficulty raised points so as to understand their meaning as well as when a normal person reads a printed book. This power of the blind person is developed only after a long period of learning, and depends on the appreciation of very deli- cate tactile impressions. I must point out, moreover, that the method of deciding by means of a pair of compasses gives information only with regard to one side of the tactile sense. However, although we admit that blind people do not really gain anything in the four remaining senses, there is developed in them a special kind of sensibility, which is spoken of in their case as a sixth sense, the "sense of obstacles." Blind people, especially those who have lost their sight in youth, acquire a surprising habit of avoiding obstacles and of recognising at a distance objects round PESSIMISM AND HEALTH AND AGE 259 about them. Blind children, for instance, can play in a garden, without knocking themselves against the trees. Dr. Javal ^ states that some blind people, when passing in front of a house, can count the ground floor windows. A professor, who had been blind from the age of four years, could walk in the garden without striking against a tree or post. He appreciated a wall at a distance of two metres from it. One day, going for the first time into a large apartment, he_ recognised the presence of a big piece of furniture in the middle, which he took to be a billiard table. Another blind man, walking in the street, could distin- guish houses from shops and could count the number of doors and windows. The existence of this sense of ob- stacles rests upon so many exact facts that it is indubitable. The opinions as to the mechanism by which it operates, however, are very varied. Dr. ZelP thinks that it is not a sense peculiar to blind people and " that those of normal sight could equally well acquire it by practice, because it exists in nearly everyone without being noticed." None the less, there are some blind people who, even in the course of years, do not acquire it. M. Javal, for instance, learnt to read with his fingers extremely well, but was never able to distinguish obstacles at a distance. The most probable hypothesis refers this sixth sense to the action of the tympanic membrane and the auditory apparatus. It is known that loud noise makes it more difficult to perceive obstacles, and snow, by dulling the sound of steps, has a precisely similar effect. Blind tuners, in whom the sense of hearing is well developed, have the sixth sense very marked. The examples I have given show that the human body possesses senses which come into operation only in special * Entre aveugles, Paris, 1903. ^ Der Blindenfreund, Feb. 15th, 1906, S 2 26o THE PROLONGATION OF LIFE conditions, and which require a special education. The "sense of life" to a certain extent comes within this category. In some persons it develops very imperfectly,^ generally revealing itself only late in life, but some- times a disease or the danger of losing life stimulates its earlier development. Occasionally in persons who have tried to commit suicide, a strong instinct of life wakens suddenly, and impels them to make frantic efforts to escape. It happens, therefore, that the sense of life develops sometimes in healthy people, sometimes in those who suffer from acute or chronic disease. These variations are parallel with the development of the sexual instinct; which in some women is completely absent and in others develops only very late. In certain cases, it is awakened only by special conditions, such as child-birth, or even some defect of health. As the sense of life can be developed, special pains ought to be taken with it, just as with the making perfect of the other senses in the blind. Young people who are inclined to pessimism ought to be informed that their condition of mind is only temporary, and that according to the laws of human nature it will later on be replaced by optimism. PART VIII GOETHE AND FAUST I Goethe's youth Goethe's youth— Pessimism of youth— Werther— Tendency to suicide — Work and love — Goethe's conception of life in his maturity There can be drawn from analysis of the lives of great men information that is very important in the study of the con- stitution of man. I have chosen Goethe for several reasons. He was a man of genius distinguished by the comprehensive character of his ability. He was a poet and dramatist of the highest rank, his mind was stored with the most varied knowledge, and he contributed to the ad- vancement of natural science. As minister of state and as the director of a theatre, he was occupied with practical affairs. He reached the age of eighty-three years, and he passed through the phases of life in relatively normal circumstances ; in his many writings there are most valuable facts which throw a keen light on his life and nature. The Goethe cult in Germany has brought about the existence of fuller biographical details than exist regarding any other great man. He aspired to lead "the higher life," and, throughout his existence, he occupied himself with the most serious problems of humanity. It is not surprising that Goethe became a subject of 262 THE PROLONGATION OF LIFE investigation for me, but as the main facts as to his history are widely known I need not elaborate them here. Goethe was reared in circumstances that were favourable in every respect, and from his earliest years showed re- markable traits. As his memory was good and his ima- gination vast, the study of ancient and modern languages and the routine curriculum of a classical education were little more than an amusement to him. The rich library of his father placed all sorts of books at his disposal, and whilst he was still young he devoted himself to reading with the enthusiasm and passion that were the chief quali- ties of his character. When he was fifteen years old he began to write verses, although he was still unconscious of his destiny as a poet. He intended to be a learned man, and looked forward to the career of a professor. At the age of sixteen, he entered the University of Leip- zig with the intention of studying natural science seriously. Law and philosophy interested him but little ; he turned to natural science and medicine, although his actual study was rather superficial. His disposition was lively and rest- less ; he made many friends, frequented the theatre and plunged into all kinds of gaiety. Extracts from letters he wrote during this period show the kind of life he led. When he was a student, eighteen years old, he wrote to a friend, " And so good-night; I am drunk as a hog." A month later, to the same friend, he summed up his life as a "delirium in the arms of Jetty." He graduated in law at Strassburg, and became a barrister, but realising that such a career was unsuitable, he became a man of. letters, encouraged by the success of his first literary efforts. From the point of view of a writer, he sought all kinds of experiences. He devoted himself to literature and science. GOETHE'S YOUTH 263 including even the occult sciences, and frequented the theatre and society. He was specially attracted by the imaginative side and gave little thought to the problems of science. " I must have movement," he wrote in one of his note-books. When he was young, his temper was violent and he fell into fits of passionate rage. His contemporaries have re- lated that when he was in such a condition he would destroy the illustrations and tear up the books on his work-table. These experiences have been vividly described in his famous romance. The Sorrows of Werther. I shall give a few extracts to show the exact state of mind of the young pessimist. "It is the fate of some men not to be under- stood." " Human life is a dream ; I am not the first to say that, but the idea haunts me. When I reflect on the narrow limits which circumscribe the powers of man, his activities and intelligence; when I see how we exhaust our forces in satisfying our wants and that these wants are for no more than the prolongation of a miserable existence; that our acquiescence in so much is merely resignation engendered by dreams, like that of a prisoner who has covered the walls of his cell with pictures and new landscapes; such things, my friend, plunge me into silence." "Our learned teachers all agree that children do not know why they have desires; but that grown men should move on the earth like children, and, like these, be ignorant whence they have come and whither they go, like these strive little for real things, but be ruled by cakes and sweets and rods ; no one will believe such things, though their truth is patent. 1 admit readily (for I know what you will say) that they are the happiest men who live from day to day like children, who play with their dolls, dress them and undress them, who reverence the cupboard where mamma keeps the 264 THE PROLONGATION OF LIFE gingerbread, and who, when they have got what they wish, cry, with their mouths full, ' How happy we are ! ' " Werther proclaimed his pessimism before his romance with Charlotte, and it was his view of life that made his love-affair turn out unhappily. But the fame of Goethe's Werther was due, not to the tragic fate of the young lover, but to the general views which were in harmony with the conception of the world held by the best minds of the time. Byronism was born before Byron. Werther affords a good illustration of the disharmonies in the development of man's psychical nature. Inclination and desires develop extremely strongly and before will. Just as in the development of the reproductive functions, as I showed in The Nature of Man, the different factors develop unequally and unharmoniously, so there is in- equality and disharmony in the order of the appearance of the higher psychical faculties. Sexual appreciation and a vague attraction to the other sex appear at a time when there can be no possibility of the normal physical side of sex, with the result that many evils come about in the long period of youth. The precocious development of sensi- bility brings about a kind of diffused hyperzesthesia which may lead to trouble. The infant wishes to lay hold of everything he sees before him ; he stretches out his arms to grasp the moon and suffers from his inability to gratify his desires. In youth there is still well-marked disharmony. Young people cannot realise the true relations of things, and formulate their desires befbre they understand that their will- power is not strong enough to gratify them, as will is the latest of the human powers to develop. Werther fell in love with a kindred spirit and gave way to his passion without consideration of the difficulties, Charlotte being already betrothed to another. This is the GOETHE'S YOUTH 265 plot of the tragedy of the young man, who committed! suicide, having given way to pessimism. He had not the will-power to conquer his sentiments and so fell into a state of lassitude,, until, weary of life, he could see no other end than to blow out his brains. 1 need not linger over the last phase of the story of Werther, for it is the character of Goethe himself that is of interest. Goethe was able to subdue his passion for Lotte, and, after many amorous woes, consoled himself with another woman . Notwithstanding this difference, it is cer- tain that in Werther, Goethe was telling part of the story of his own youth. Goethe him.self is a witness to this, for in a letter to Kestner he wrote that " he was at work on the artistic reproduction of his own case." The letter was written in July, 1773, whilst Goethe, then a writer twenty- four years old, was relating the sorrows of young Werther, The general tendency of Werther has been described excellently by Carlyle.^ " Werther," he wrote, " is but the cry of that dim, rooted pain, under which all thoughtful men of a certain age were languishing ; it paints the misery, it passionately utters the complaint ; and heart and voice, all over Europe, loudly and at once responded to it." Werther was " the first thrilling peal of that impassioned dirge which, in country after country, men's ears have lis- tened to, till they were deaf to all else." In the pessimistic period of his life, Goethe often cherished the idea of suicide. In his biography he relates that at this time he used to have, by his bedside, a poisoned dagger, and that he had repeatedly tried to plunge it in his bosom. Of these times he wrote to his friend Zelter* — "I know ' Critical and Miscellaneous Essays, vol. i, pp. 164-5, '" the E.ssay on Goethe. 2 Briefwecksel zwischen Goethe und Zelter. Letter of Dec. 3, 18 12. 266 THE PROLONGATION OF LIFE what it has cost me in effort to resist the waves of death." The suicide which was the subject of the end of his romance made a deep impression upon him. Although he overcame his passion for Charlotte, his view of life remained tinged with pessimism for many years; in a note-book of 1773, for instance, he wrote " I am not made for this world. "^ These words are the more striking as they date from a period when exact ideas regarding the adaptation of the organism and the character to the environment did not exist. Goethe, with his too delicate sensibility, felt himself out of harmony with his environment. It is very interesting to trace Goethe's subsequent de- velopment and the transformation of a youthful pessimist into a convinced optimist. Goethe found a remedy for his crises of grief in work, poetical creation and love. He declared that the mere describing his woes on paper brought assuagement. The tears that they shed console women and children ; and the poetry in which he expresses his suffer- ing consoles the poet. Goethe's romance with Charlotte was not quite at an end when he found himself ready to love her sister Helen. He wrote to Kestner in December, 1772: — "I was about to ask you if Helen had arrived, when I got the letter telling me of her return." " To judge from her portrait she must be charming, even more charm- ing than Charlotte. Well, I am free and I am thirsting for love." " I am here at Frankfort again with new plans and new dreams, and all will be well if I find someone to love." Soon afterwards, in another letter to Kestner, he wrote: — "Tell Charlotte that I have found here a girl whom I love with all my heart; if I wanted to marry, 1 should choose her before anyone else." As he had not yet realised his true vocation, Goethe became a court minister at Weimar. He devoted himself ' Quoted in Moebius' Goethe, vol. ii, p. 80. GOETHE'S YOUTH 267 to his duties with an enthusiasm that carried him far beyond the usual affairs of state. He wished to deepen his know- ledge of such administrative problems as the construction of roads and the management of mines, and he studied geology and mineralogy with a real zest. Forest adminis tration and agriculture led him seriously into botany, and as he had the direction of a school of design, he thought il necessary to learn anatomy. Such varied work gave him a real taste for science. It was no longer the superficial interest that characterised his work at Leipzig and Strass- burg but a true devotion which led him to important dis- coveries, some of which have become classic. Even such varied occupations did not absorb his pro- digious genius. In his leisure he wrote poetry and prose. Engrossed in so much work, he was happy. His discovery of-; the human intermaxillary bone suffused htm with joy. His intense activity was strengthened by his love for Madame von Steia, a love that he declared was " a life-belt supporting him in the sea." A few hours with her in the evenings set free his soul. The powerful influence of love on the life of Goethe was specially prominent in this period when he was passing from pessimistic youth to optimfstic maturity. Being forced to separate from Madame von Stein, he gave way to grief that plunged him again in the worst hours of his life. At the age of thirty-seven he fell back into a crisis like that of the days of Werther. " I have discovered," he said in 1 786, "that the author of Werther would have done well to blow out his brains when he had finished his work." Soon afterwards he wrote that " death would have been better than the last years of his life." This relapse into pessimism was shorter and less acute than his first experience. He began to find that frequently his delight in existence and sense of life were proved by his 268 THE PROLONGATION OF LIFE fear of death. When he was little more than thirty years old, he began to take precautions against the chance of his death. He wrote to Lavater : — "I have no time to lose; I am already getting on in years, and it may be that fate will destroy me in the midst of my life." On all sides his wish to live and his shrinking from death reveal themselves. It was at this time, a few days after his thirty-first birthday, that he wrote those famous lines, counted amongst the finest of his poetry, on the summit of the Gickelhahn, on the wall of a small room^ and which end with the presenti- ment of his own death, " Before long, you also will be at rest." The crisis through which he passed at the age of thirty- seven, as the immediate result of his separation from Madame von Stein, but perhaps also partly due to brain fatigue, brought about his sudden departure from Weimar and his long sojourn in Italy. There he came to life again, and everything interested him, archaeology, art and nature. The joy of life came back to him, and he soon consoled him- self for the lost love of the blue-stocking Baroness in the arms of a pretty, blue-eyed girl of Milan. This girl, whose name was Maddalena Riggi, like Charlotte, was already be- trothed, a circumstance, however, that had a different result. Even after she had given up the man to whom she had been engaged, Goethe avoided any permanent bond and soon abandoned her definitely. He chose to associate with Faustine, another Italian girl, with whom he lived during the last period of his stay at Rome. This affair, which was less ideal and much simpler than his love for Madame von Stein, he has described in his Roman Elegies, which throw a vivid light on his temperament. I shall give some char- acteristic extracts. " A sacred enthusiasm inspires me on this classic soil; the old world and the world around me raise their voices GOETHE'S YOUTH 269 and draw me to them. Here I follow the ideas and turn over the pages of the ancient writers, giving myself no rest whilst day lasts and ever reaching new delights. By night love calls me to other cares ; and if I am only half a philo- sopher, I am twice happy. But may I not say that I am also learning when my eye follows the contours of a loving breast, when with my hand I trace the lines of her form ? It is then that I understand marble, I think and compare, I see with an eye that touches and touch with a hand that sees." " Often I have made verses in her arms; often my playful finger has softly beaten out my hexameters on her back. As she breathes in her sweet sleep, her breath burns me to my innermost soul." ^ His stay in Italy brought Goethe definitely to maturity. On this important stage in his life let us hear his bio- grapher, Bielschowsky. " The voyage to Italy made a new man of him. His sickliness and nervousness dis- appeared. The melancholy which led him to think of early death and made him regard death as better than the former conditions of his life was replaced by a sublime serenity and joy in living. The taciturn and preoccupied man who in no society abandoned his grave thoughts had become happy as a child " (vol. i, p. 412). " From this time on, in calm and enviable security, he passed through the cycle of life which seemed so mysterious to others. Goethe became the serene Olympian, the wonder of posterity, whilst many of his contemporaries no longer saw in him the passionate pilgrim " (ibid., p. 417). It was after reaching the age of forty years that Goethe entered on the optimistic phase of his life. * 7%* Fty/A Rntnan Elegy, Blaze's French translation, 1873 p. 186. Some of Goethe's biographers, and amongst them G. H. Lewes, maintain that these lines relate to Christine, Goethe's wife. This is erroneous ; thejr refer to Faustine (see Bielschowsky, i, p. 517)1 II GOETHE AND OPTIMISM Goethe's optimistic period — His mode of life in that period — Influence of love in artistic production — Inclinations towards the arts must be regarded as secondary sexual characters — Senile love of Goethe — Relation between genius and the sexual activities The moral equilibrium of the great writer was not estab- lished once for all. In the course of his life, Goethe had several relapses into pessimism which, however, were ephe- meral, and after which he became a man as complete and harmonious as was possible in the circumstances of his life. He reached a serene old age, and his activity did not relax until after his eightieth year, when he died. As 1 have already said, Goethe realised the value of life in good time. Having become an optimist, he experienced the joy of existence and coveted as much of it as possible. When he was an old man, he declared that life, like the Sibylline books, became more valuable the fewer of them were left. There appeared in him a normal phase of human nature. The conditions under which he lived, however, were far from ideal. His health was indifferent. In his youth he suffered from severe hcemorrhage, probably tuber- culous, and throughout his life he was subject to various more or less serious maladies, such as gout, colic, nephritis, and intestinal troubles. His habits were unwholesome. He GOETHE AND OPTIMISM 271 was brought up in a region of vineyards, and in his youth he acquired the habit of drinking wine in quantities cer- tainly harmful. This he himself realised, and when he was thirty-one years old, after he had acquired the instinct of life, he gave it serious attention. " I wish I could abstain from wine," he wrote in his note-book. Some weeks later he wrote, " I now drink almost no wine." ^ But he had not the strength of character to remain tem- perate, and soon after his decision, he had fits of bleeding at the nose, which he attributed to " having taken some glasses of wine." ^ To his last day, he took wine regularly, and sometimes to excess. J. H. Wolff, who dined with him at Weimar, when he was in his eightieth year, was sur- prised by his appetite and by the quantity of wine he drank. " In addition to other food, he ate an enormous portion of roast goose, and drank a bottle of red wine."^ In Eckermann's interesting narrative of the last ten years of Goethe's life (1822 — 1832) there is repeated mention of wine. Goethe seized every occasion to drink it. Some- times it was the visit of a stranger, sometimes a present of some famous vintage. It was said that he drank from one to two bottles of wine daily (Moebius). None the less, he was convinced that wine was not good for intellectual work. He had remarked that when his friend Schiller had drunk more than usual, to increase his strength and stimulate his literary activity, the result was deplorable. He said to Eckermann (March 11, 1828), "He will ruin his health and will spoil his work. That is why he has made the faults the critics have pointed out." In another conversa- tion (March 11, 1828) he stated that what was written ' Moebius' Goethe, vol. ii, pp. 84-87. 2 Moebius' Goethe, vol. ii, pp. 84-87. ^ Quoted by Bode in Goethe's Lebenskunst, Berlin, 1905, p. 59. 272 THE PROLONGATION OF LIFE under the influence of wine was abnormal and forced, and ought to be deleted. Love was the great stimulus of Goethe's genius. The love affairs, the histories of which fill his biography, are well krjown. Many have been shocked by them; others have tried to justify them. It has been suggested that his disposition made it necessary for him to impart his ideas and obtain sympathy for them, and that his love for women was the expression of a purely artistic feeling and had nothing in common with the ordinary passion. The truth is that artistic genius and perhaps all kinds of genius are closely associated with sexual activity. I agree with the proposition formulated by Dr. Moebius^ that "artistic proclivities are probably to be regarded as secondary sexual characters." Just as the beard and some other male characters are developed as means of attracting the female sex, so also bodily strength, strong voice and many of the talents must be regarded as due to the need to fulfil the sexual relations. In primitive conditions woman worked more than man; man's superior force served him principally in fighting with other males, the object of the combat-s usually being possession of a woman. Just as a victorious combatant covets the presence of a woman as witness of his prowess, so an orator speaks better in the presence of a woman to whom he is devoted. Singers and poets are stimulated in their arts by the love they awaken. Poetic genius is intimately associated with sexual power and castration inhibits it. Just as castrated animals retain their physical strength, but become changed in character, losing in particular their combative nature, so a man of genius loses much of his quality with the sexual function. Amongst the eunuchs on record, Abelard is the only poet, 1 Ueberdie Wirkungen d. Castration, Halle, 1903, p. 82. GOETHE AND OPTIMISM 273 but Abelard was forty years old when he ceased to be a man, and at the same time he ceased to be a poet. Many singers have been eunuchs, but they have been merely executants, and have tal 1831). None the less, he continued his work, in par- ticular revising the last two chapters of the second part of Faust. When he had finished them, Goethe was extremely pleased. "I can consider," he said, "any days which come to me yet as a real gift, as it is a matter of no moment if I write anything more or what such work should be " (Eckermann, June i, 1831). Goethe gave Faust one hundred years of life, and it is probable that he thought of that period as his own span. Although he did not reach it, he approached it, after having lived a most active life, full of most valuable lessons for posterity. IV GOETHE AND " FAUi»T " Faust the biography of Goethe — The three monologues in the first Part — Faust's pessimism — The brain-fatigue which finds a remedy in love — The romance with Mar- guerite and its unhappy ending " Goethe was Faust, Faust Goethe," said the biographer ' of the great poet (Bielschowsky, vol. ii, p. 645). Most people admit that in Faust Goethe gave his auto- biography on a more detailed scale than in Werther. Why then should I follow my analysis of Goethe himself, which was based on exact facts, with an analysis of Faust ? I do so because in addition to the biographical details in Faust, there are many ideas which illuminate the poet's conception of life. Goethe's life explains Faust, and Faust explains the soul of its author. And I am con- vinced that an accurate study of so great a man is of high importance in the investigation of human nature. The two Parts of Faust correspond with two distinct periods in Goethe's life. In the first Part, Faust was pes- simistic, in the second optimistic. Although many of the high problems that occupy humanity are raised and dis- cussed in Faust, love is the centre on which the drama turns. In the first Part, conceived and for the most part written 284 THE PROLONGATION OF LIFE during his youth, the chief theme is the love of a young man for a pretty and attractive girl towards whom the hero acts in a fashion opposed to conventional morality. As in most of his principal works, Goethe has made an episode in his own life the basis of Faust. It is the well-known story of Frederique, the daughter of a clergyman, for whom the brilliant young author conceived a violent passion and who returned his affection with a deeper and more enduring feeling. Goethe was alarmed at the possibility of definitely settling his future, and deserted the poor victim of love in an unfortunate state. 'Later on, he confessed to the Baroness von Stein that he had abandoned F"rederique at a time when his desertion was likely to cause the death of the poor girl. " I had wounded to the quick," he wrote (Bielschow- sky, vol. i, p. 135), "the best heart in the world, and I had to repent of it long and almost unendurably." As an atonement, he made Frederique the heroine of "Goetz". and of " Clavigo, " but not thinking these worthy of her, he immortalised her as the Marguerite of Faust. A learned doctor, skilled in all human knowledge, but who had found no satisfaction in his studies, found consola- tion in the beauty and charm of a young girl with whom he fell passionately in love. It will be interesting to trace the psychological process which induced him to leave the scene of his scientific studies tor the streets and resorts where he found Marguerite. Although Faust was represented as an old man, who had had time enough to absorb all human learning, his image bears the stamp of green youth. " Discontented with all his knowledge, he wished tp know the secret entrails of the world, to be a witness of the centre of all activity, to unveil the principle of life." ^ These are the demands of a youQg ' The word Samen of the original is the expression of the alchginists for the " principle of life," GOETHE AND "FAUST" 285 man seeking to resolve the most intricate problems at one stroke. The speech in question dates from the period of Werther, when Goethe was twenty-five years old, and for that reason leaA^s no very serious impression.' The second monologue, which ends with the attempt to take poison, is later, and is absent in the edition of 1790 (Frag- ment). It was revised when Goethe had reached his fiftieth year, and displays a riper maturity. Although lacking exactness, it depicts in an interesting fashion the miseries of life. Some alien substance more and more is cleaving To all the mind conceives of grand and fair ; When this world's Good is won by our achieving, The Better, then, is named a cheat and snare. The fine emotions, whence our lives we mould. Lie in the earthly tumult dumb and cold. If hopeful Fancy once, in daring flight, Her longings to the Infinite expanded, Yet now a narrow space contents her quite, Since Time's wild wave so many a fortune stranded. Care at the bottom of the heart is lurking; Her secret pangs in silence working, She, restless, rocks herself, disturbing joy and rest; In newer masks her face is ever drest, By turns as house and land, as wife and child, presented,— As water, fire, as poison, steel; We dread the blows we never feel. And what we never lose is yet by us lamented. Fear of the evils which lie in wait for us and against which we can make no provision render life insupportable. Faust's frame of mind as described in these lines recalls Schopenhauer, who was always afraid of something; fear, sometimes of thieves, sometimes of diseases, tormented ' Erich Schmidt, Goethe's Faust in urspriinglicher Gestalt, 6th edit., Weimar, 1905, p. i. 2 Faust, Bayard Taylor's translation. London : Wame & Co., pp. 20-21. 286 THE PROLONGATION OF LIFE him. He would never go to a barber's to be shaved, and always carried his own drinking cup with him. "Is it not better to end such a life, and to kill oneself, even if it mean annihilation?" asked Faust. He took up the poisoned goblet and put it to his lips, but, arrested by singing and the sound of bells outside, he refrained, and life laid hold of him. Not religious faith, however, but memories of childhood, "the happy sports of youth and the gay festivals of spring " were the agencies that recalled Faust to the earth. He went out of doors, mingled with the crowd, tried to amuse himself amongst men, and savoured the beauty of the new-born spring, but all these could not make him forget the evil of life. He met his pupil, talked with him, and again displayed his pessimism. O happy he, who still renews The hope, from Error's deeps to rise for ever ! That which one does not know, one needs to use; And what one knows, one uses never.' Then follows the celebrated monologue of Faust over which so many commentators have lost their heads and wasted oceans of ink. Two souls, alas ! reside within my breast, And each withdraws from, and repels, its brother. One with tenacious org^ans holds in love And clinging lust the world in its embraces; The other strongly sweeps, this dust above. Into the high ancestral spaces.'' On this passage has been built up a whole theory of "double natures" vvith which has been incorporated the dualism of Manicheism, the two natures of Christ and what not besides.^ ' Op ctt., p. 32. 2 Op. cit., pp. 33, 34. * Details of this will be found in Kuno Fischer's GoetMs Faust, pp. 328-330. GOETHE AND "FAUST" 287 There exists in literature no better expression of human disharmony than this monologue "of the two souls." It portrays the unbalanced condition so frequent in youth and is a valuable indication of the real youth of Faust. On his return to his study, Faust again revealed his pessimism. But ah ! I feel, though will thereto be stronger, Contentment flows from out my breast no longer. Why must the stream so soon run dry and fail us. And burning thirst again assail us? Therein I 've borne so much probation ! ' It is at this point that Faust addresses the Spirit " that denies " and that is called " sin " and " evil." This spirit invokes before his eyes "the fairest images of dreams," that is to say, a woman's body in its beautiful nudity. Faust declares himself Too old to play with passion, Too young to be without desire.' Pursued by desire .... when night descends, how anxiously Upon my couch of sleep I lay me. There, also, comes no rest to me ; But some wild dream is sent to fray me.' So that Death is desired, and Life a thing unblest. O fortunate, for whom, when victory glances, The bloody laurels* on the brow he bindeth ! Whom, after rapid, maddening dances. In clasping maiden-arms he findeth ! ' Faust thus reached the ecstasy of passion. Soon after- wards in the Witches' kitchen, he saw in a mirror a " heavenly form " and cried : — O lend me, I^ove, the swiftest of thy pinions, And bear me to her beauteous field. > Op. cit, p. 36. 2 op. cit, p. 45 ' Op. cit., p. 46. * Od. cit., p. 46. 288 THE PROLONGATION OF LIFE A woman's form, in beauty shining! Can woman, then, so lovely be? And must 1 find her body, there reclining; Of all the heavens, the bright epitome? Can Earth with such a thing be mated ? ' Discontent with life, sense of the insufficiency of human knowledge and the most gloomy pessimism lead to the passion of love which, eventually, after many devious paths, throws Faust into the arms of Marguerite. The story is one of the world's great romances and everyone knows it. Faust all unconsciously was following the prescription of Brown-S^quard. Brain-fatigue had made the continuation of the study which caused it impossible. The condition is plainly stated in the following lines : — The thread of Thought at last is broken, And knowledge brings disgust unspoken. Let us the sensual deeps explore.'' The brain has refused to work, and blind instinct, in the guise of dreams, whispers that, there is in the organism something that can restore the intellectual forces. This something, however, is what is called sin, and much courage is needed to plunge into it. Without this evil, life cannot last. Faust has to choose between love and death, and chooses love. The end of the romance of Goethe and Frederique was bad, and that of Faust and Marguerite was still worse. The poet painted it in the most sombfe colours. Marguerite killed her child, poisoned her mother, became crazy, and was beheaded. Faust's cup of misery was filled to the brim ; he blamed his evil genius, he made desperate efforts to save the poor woman, and cried "O that I had never been born," To sum up : in the first Part, Faust is a young, learned man who expects too much from science and life, and whose ' Op. cit., p. 71. s Op. at, p. 51. GOETHE AND "FAUST" 289 genius requires extra-conjugal love as a stimulant; he is unbalanced and inevitably pessimistic. It is not surprising that his life goes badly, and that his conduct leaves him much to repent of. But although, at first, a vague general discontent nearly drives him to suicide, later on the terrible evil which he had wrought on a poor creature he loved pas- sionately did no more than plunge him into misery that was bitter but far from mortal. His mind had developed far in the direction of optimism. The crisis through which he passed, serious as it was, ended by his return to a life of great activity and enterprise. V THE OLD AGE OF FAUST The second Part of Faust is in the main a description of senile love — Amorous passion of the old man — Humble atti- tude of the old Faust — Platonic love for Helena — The old Faust's conception of life — His optimism — ^The general idea of the play The first Part of Faust was acclaimed by the world almost as soon as it appeared, but tfie second Part met a very cold reception. Everyone knows and reads the first Part; the second Part has few readers, and these chiefly poets and dramatists. No doubt it has more effect on the stage than when it is read, but this is due to subsidiary features in which it resembles a fine ballet. There is general agree- ment that the real meaning of the second Part is obscure, complex and difificult to interpret. Many literary critics have racked their brains in the effort to discover the author's central idea. When Eckermann, who per- suaded Goethe to revise and finish the second Part, asked what was the meaning of some of the scenes in it, Goethe evaded the question and played the sphinx. Thus, with regard to the famous "mothers" Goethe answered, with a mysterious airs — "You have the manu- script ; study it, and see what you can make of it " (January ID, 1830). G. H. Lewes, although one of Goethe's most resolute admirers, admitted the impossibility of grasping THE OLD AGE OF FAUST 291 the sense of the second Part. The Wanderjahre and the second Part of Faust were arsenals of symbols, and it pleased the old poet to see acute critics labouring to inter- pret them whilst he was silent and refused to help them. Lewes thought that Goethe, so far from showing the smallest wish to clear up their difficulties, took a pleasure in giving them new problems to puzzle over. Lewes himself thought that the second Part was poor in idea and execu- tion, and admitted that he had failed after repeatedly trying to get a conception of it that would reveal its beauties. In writing about it, he contented himself with giving a sum- mary of it. Now this second Part, although its general lines had^been laid down for long, was actually written during several years in the last period of the poet's life. The fact that it was composed out of the regular sequence of the Acts and Scenes gives us an important clue. The third Act and then the second Part of the fifth Act were put on paper first. Next followed the first Act and part of the second ; the classical Walpurgis night was written in 1830, the fourth Act in 1831, and last of all the beginning of the fifth Act. As the second Part of Faust is a crowded motley, con- taining many subjects, obviously of minor importance, such as the volcanic theory of the earth and the disquisition on paper-money, the key-note may be found in the portions which were first composed. Now Act IIL contains the story of Helena, and the second part of Act V. Faust's activity for the general welfare. Setting out from the conception that the works of Goethe reflect the acts and incidents of his own life, I shall try to explain on that basis the meaning of the most obscure of his writings. I have already stated that love was the stimulus of u 2 292 THE PROLONGATION OF LIFE Goethe's activity in youth and age ; it is the scarlet thread running through his history. There was no difficulty in his using his love for Frederique as material for a play ; that a young man should love a young girl was natural enough. The story of an old man enamoured of a young beauty was quite another matter. It was said that one of the reasons that prevented his marriage with Ulrique de Lewetzow was the fear of ridicule (Lewes, op. cit., ii, p. 345), a fear that plays a large part in human affairs. It is easy to under- stand that the old poet was in a difficulty when he came to write of seriile love. Faust's love for Helena was not that of a supposed old man who became young by doffing his beard and changing his cloak, but of a real old man whom no mystery nor magic was to make young again. And yet old Faust's love was a true passion, and Goethe has written rio finer lines than those describing it. When the second Part begins, Faust has passed through the terrible crisis of the first Part. Wearied and restless, he seeks a new mode of life. Life's pulses now with fresher force awaken To greet the mild ethereal twilight o'er me; This night, thou, Earth ! hast also stood unshaken, And now thou breathest, new-refreshed before me, And now beginnest, all thy gladness granting, A vigorous resolution to restore me. To seek that higher life for which I'm panting.* The invoked image of the most beautiful woman in the history of the world transforms Faust's desire of love into ■an overwhelming passion. Have I still eyes? Deep in my being springs The fount of Beauty, in a torrent pouring I A heavenly gain my path of terror brings. The world was void, and shut to my exploring, — ' Op. cit, p. 151. THE OLD AGE OF FAUST 293 And, since my priesthood, how hath it been graced 1 Enduring 'tis, desirable, firm-based. And let my breath of being blow to waste, If I for thee unlearn my sacred duty ! The form, that long erewhile my fancy captured, That from the magic mirror so enraptured. Was but a frothy phantom of such beauty 1 'Tis Thou, to whom the stir of all my forces. The essence of my passion's courses, — Love, fancy, worship, madness, — ^here I render.' In the throes of this passion, Faust is tortured by jealousy when he sees the lovely woman clinging to and kissing a young man. He desires her at all costs. Am I nothing here? To stead me, Is not this key still shining in my hand? Through realms of terror, wastes and waves it led me, Through solitudes, to where I firmly stand. Here foothold is ! Realities here centre ! The strife with spirits here the mind may venture, And on its grand, its double lordship enter ! How far she was, and nearer, how divine 1 I'll rescue her and make her doubly mine. Ye Mothers ! Mothers ! Crown this wild endeavour I Who knows her once must hold her, and for ever.' The disappearance of the beautiful woman so moved Faust that he fainted and fell into a prolonged sleep. As soon as he recovered consciousness he asked : " Where is she? " and set out to seek for her. When he learned that Chiron had already carried off Helena on his back Faust cried out : — Her didst thou bear? Chiron: This back she pressed. Faust: Was I not wild enough, before; And now such seat, to make me blest! O, I scarcely dare To trust my senses ! — tell me more 1 She is my only aspiration ! Whence didst thou bear her — to what shore?* ' Op. «■/., p. 203. 2 Op. di. p. 205. 3 op^ ^-f., p. 330. 294 THE PROLONGATION OF LIFE Thou saw'st her once ; to-day I saw her beam, The dream of Beauty, beautiful as Dream ! My soul, my being, now is bound and chained ; I cannot live, unless she be attained.' Chiron found this attitude of passionate emotion so strange that he advised Faust to take care of his Jiealth, After many wanderings and difficulties Faust again met the woman he coveted and spoke to her as follows : — What else remains, but that I give to thee Myself, and all I vainly fancied mine? Let me, before thy feet, in fealty true. Thee now acknowledge, l.ady, whose approach Won thee at once possession and the throne ! ' This language, so very different from what the same man had formerly addressed to Marguerite, is much more like that of an olJ lover to a young beauty whom he admires. When Helena invited Faust to sit on the throne beside her, he replied : — First, kneeling, let the dedication be Accepted, lofty Lady ! Let me kiss The gracious hand that lifts me to thy side. Confirm me as co-regent of thy realm. Whose borders are unknown, and win for thee Guard, slave and worshipper, and all in one ! ' The old man in the throes of a passion so great that he was wholly absorbed ,by it did not dare to address the beloved woman except in the most humble terms. Helena made no declaration of love, but was complacent to him, and when Faust suggested : " Now let our throne become a bower unblighted," Helena agreed to follow him to a secluded and green bower. There they remained alone for some time, cared for by an old servant. The result of this union was not a child like that to which Marguerite gave birth and afterwards killed. It was a » Op- cit., p. 231. 2 Op. cit., p. 284. 3 Op. cit., p. 287. THE OLD AGE OF FAUST 295 strange and peculiar being; a boy who immediately after his birth began to leap about and to alarm his parents by the activity of his movements. Although Goethe preserved an obstinate silence when he was asked to explain many of the scenes in the second Part, he had no hesitation in explaining the significance of this astonishing child. " The child was not a human being but an allegory, in which was personified poetry, which is not bound to any time, to any place, or to any person " (Ecker- mann, December 20, 1829). Struck by the tragic fate of Byron, Goethe made the son of Faust and Helena a symbol of the English poet. Literary critics, setting out from the categorical explana- tion of Goethe himself, have declared that the union of Faust and Helena was meant to denote tTie alliance of romanticism and classicism, a marriage from which was born modern poetry, personified in its highest representa- tive, Byron. This, however, cannot be the idea of Goethe, who himself was far from an enthusiast about classicism and romanticism. " What," he said, " is all this noise about the classic and the romantic ? The essential thing is that a piece of work should be wholly good and serious ; then it will also be classic " (Eckermann, October 17, 1828). It is much more probable that Goethe intended poetry to spring from the relations between the old Faust and his adorable companion, relations of a kind 'to be included in so-called platonic love. Such love inspires the creation of perfect work even in an old poet, when he is stimulated by a beautiful woman. ^ When Faust and Helena emerged from the grotto with their son, Helena said: — Helena: Love, in human wise to bless us, In a noble pair must be; 296 THE PROLONGATION OF LIFE But divinely to possess us, It must form a precious Three. Faust: All we seek has therefore found us; I am thine and thou art mine 1 So we stand as love hath bound us; Other fortune we resign.' After the death of her son, Helena abandoned Faust, leaving him her garments : — Helena : Also in me, alas 1 an old word proves its truth. That Bliss and Beauty ne'er enduringly unite. Torn is the link of Life, no less than that of Love-, So, both lamenting, painfully I say : Farewell 1 And cast myself again, — once only, — in thine arms.' After this crisis the old Faust sought to console himself in the boSom of nature, just as after the terrible catastrophe with Marguerite the contemplation of nature had given him the strength to live. On this occasion he reached the sum- mit of a high mountain from which he watched the chang- ing vapours of a cloud which seemed to him to assume the form of female beauty. But Faust was old, and now saw only memories of love. He cried out: — Yes 1 mine eyes not err 1 — On sun-illumined pillows beauteously reclined. Colossal, truly, but a godlike woman-form, I see ! The like of Juno, Leda, Helena, Majestically lovely, floats before my sight ! Ah ! now 'tis broken I Towering broad and formlessly, It rests along the east like distant icy hills, And shapes the grand significance of fleeting days. Yet still there clings a light and delicate band of mist Around my breast and brow, caressing, cheering me. Now light, delaying, it soars and higher soars. And folds together. — Cheats me an ecstatic form. As early-youthful, long-foregone and highest bliss? The first glad treasures of my deepest heart break forth; Aurora's love, so light of pinion, is its type, The swiftly-felt, the first, scarce-comprehended glance, Outshining every treasure, when retained and held. * Op. cit:, p 298. Op. cit., p. 305. THE OLD AGE OF FAUST 297 Like Spirjtual Beauty mounts the gracious Form, Dissolving not, but lifts itself through ether far. And from my inner being bears the best away.' This state of mind resembles Goethe's condition after the rupture with Ulrique. Love and poetry aUke were over for him. None the less his craving for the higher life was not yet weakened. The desire to live was still very strong in the old Faust. But now he no longer as in the days of his youth dreamed of an ideal which could not be attained. When Mephisto- pheles asked him ironically : — Then might one guess whereunto thou hast striven? Boldly-sublime it was, I'm sure. Since nearer to the moon thy flight was driven, Would now thy mania that realm secure? Faust : Not so ! This sphere of earthly soil Still gives us room for lofty doing. Astounding plans e'en now are brewing: I feel new strength for bolder toil.^ Such optimistic language, extraordinarily different from Faust's lamentations in the first Part, becomes still more marked. When he was approaching his centenary he made the following profession of faith : — I only through the world have flown : Each appetite I seized as by the hair; What not sufficed me, forth I let it fare. And what escaped me, I let go. I've only craved, accomplished my delight. Then wished a second time, and thus with might Stormed through my life : at first 'twas grand, completely, But now it moves most wisely and discreetly. The sphere of Earth is known enough to me ; The view beyond is barred immutably : A fool, who there his blinking eyes directeth, And o'er his clouds of peers a place expecteth ! Firm let him stand, and look around him well I This World means something to the Capable. Why needs he through Eternity to wend? He here acquires what he can apprehend.' > Op. cit., p. 309. 2 Qp_ cit, p. 313. 3 op, cit., p. 351. 298 THE PROLONGATION OF LIFE When he had reached the maturity of his wisdom, Faust organised drainage works, the object of which was to increase the area of land that could be utilised : — To many millions let me furnish soil, Though not secure, yet free to active toil; Green, fertile fields. A land like Paradise here, round about. Yes ! to this thought I hold with firm persistence ; The last result of wisdom stamps it true : He only earns his freedom and existence, Who daily conquers them anew. Thus here, by dangers girt, shall glide away Of childhood, manhood, age, the vigorous day : And such a throng I fain would see. Stand on free soil among a people free ! Then dared I hail the Moment fleeing : "Ah, still delay — thou art so fair! " The traces cannot, of mine earthly being, in aeons perish, — they are there ! — In proud fore-feeling of such lofty bliss, I now enjoy the highest Moment, — this ! ' These were the last words of the wise centenarian. It has been said that they contain the quintessence of Goethe's moral philosophy, and that they preach the sacri- fice of the individual for the benefit of society. Lewes, for instance, takes this view, holding that Faust was the ex- position of a man who had conquered the vanity of in- dividual aspirations and joys, and had come to the know- ledge of the great truth that man must live for man, and can find lasting happiness only in work for the benefit of humanity. For my own part, it seems to me that according to Goethe's Faust man must dedicate a large part of his life to the complete development of his own individuality, and that it is only in the second half of his life, when he has grown wise by experience and feels satisfied as an individual, that he should use his activity for the good of > qp. cit., pp. 354-355- THE OLD AGE OF FAUST 299 mankind. It was no part either' of the ideas of Goethe or of the nature of his work to preach the sacrifice of in- dividuality. Goethe was thus absorbed in Faust by the problem of the conflict between certain actions and guiding prin- ciples. The misdeeds of the hero in the first. Part of his life had to be redeemed. He said to Eckermann that "the key to the salvation of Faust was to be found in the Angels' Chorus " :— The noble spirit now is free, And saved from evil scheming' : Whoe'er aspires unweariedly Is not beyond redeeming.' However, that of which he did not speak, and which none the less was most important in Faust and in Goethe himself, is the action of love as a stimulant to artistic creation, and it was probably to this that he referred at the end of his tragedy. The mystical chorus sent up prayers in a religious and erotic ecstasy, and their mysterious song is: — The Indescribable, Here it is done; The Woman-Soul leadeth us Upward and on ! ' Although these verses have been interpreted as love which sacrifices or even love which leads to the grace of God (Bode, p. 149), it is much more probable that it is love for feminine beauty, a love which makes possible the execution of wonderful things. Such an interpretation agrees with the fact that the verses are spoken by a mystic choir which speaks of the indescribable (das Unbeschreib- liche) in which we must see the amorous passion of the old man. In such an interpretation the whole of Faust (and especially the second Part) is an eloquent pleading > Op. cit., p. 365. 2 Qp^ cit., p. 370. 300 THE PROLONGATION OF LIFE for the importance of love in the higher activity of man, in accordance with the law of human nature, which is a much better justification of Goethe's conduct than all the arguments of his interpreters and admirers. I do not agree with the common idea that the two Parts of Faust are two distinct works, but regard them as com- plementary. In the first Part we see the young pessi- mist, full of ardour and of desires, ready to make an end of his days and stopping at nothing to satisfy his thirst for love. In the second Part we have a mature old man still loving women, but in a different way, a man who is wise and optimistic, and who, having satiated the wants of his individual life, dedicates the rest of his days to man- kind, and who, having reached a century, dies extremely happy, in fact almost exhibiting the instinct of natural death. PART IX SCIENCE AND MORALITY I UTILITARIAN AND INTUITIVE MORALITY Difficulty of the problem of morality — Vivisection and anti- vivisection — Enquiry into the possibility of rational morality — Utilitarian and intuitive theories of morality — Insufficiency of these In the course of this book I have from time to time ap- proached subjects closely related with the problem of morality. For instance, in considering the prolongation of human life, it was necessary to show that extension of longevity far beyond the reproductive period of man in no way is opposed to the principles of the highest morality, although there exist races who find the sacrifice of old people in harmony with their conception of morality. Experimental biology, which lies at the root of miost of the doctrines exposed in this work, depends on vivisection of animals. There are, however, very many persons who regard it as immoral to operate on living animals when it is not for the direct benefit of these. The attempts which have been made in France and Germany to prevent or to limit vivisection in laboratories have not succeeded, bilt in England there is a severe law controlling operations on animals and submitting them to oppressive regulations to which many of the scientific men in the country are opposed. The question of experiments upon human beings is still 302 THE PROLONGATION OF LIFE more delicate. Just as formerly the examination of a human corpse could be made only in secret, so at the pre- sent time, if the slightest experiment is to be made upon a human being, it can be only by devious ways. People who are hardly shocked at all at the numberless accidents caused by automobiles and other means of transit, or in field sports, make the strongest protest against any proposal to try some new method of treatment upon a human being. A large number of people, amongst them even men of science, regard as immoral any attempt to prevent the spread of venereal diseases. Recently, in connection with the investigations into the action of mercurial ointment as a means of preventing syphilis, the members of the Faculty of Medicine in France made a public protest, declaring that it would be "immoral to let people think that they could indulge in sexual vice without danger," and that it was ' ' wrong to give to the public a means of protection in debauch."^ None the less, other men of science, equally serious, were convinced 1:hat they were performing an abso- lutely moral work in attempting to find a prophylactic against syjihilis which would preserve many people, in- cluding children and other innocent persons who, if no preventive measures existed, would suffer from the terrible disease. Such examples show the reader what confusion exists in the problem of morality. Although at every moment, in every act of human conduct, the precepts of morality must be reckoned with, even the most authoritative persons are far from agreeing as to what rules to follow. About a year ago in a Parisian journal ^ an enquiry into the subject 1 V. Tribune medicale, 1906, p. 449, * La Revue, Nov. isth and Dec. ist. UTILITARIAN MORALITY 303 of rational morality was directed to distinguished authors. The object was to discover if, at the present time, moral coirdttct could be based not on religious dogma, which binds only those who believe in it, but on rational prin- ciples. The answers were most contradictory. Some denied the possibility of rational morality, others admitted it, but in very different fashions. Whilst one philosopher, M. Boutroux, held that "morality must be founded on reason and could have no other foundation," a poet, M. Sully-Prudhomme, turned to feeling and conscience as the basis of morality. According to him, " in the teaching of morality, it is the* heart and not the mind which is at once master and pupil." In the contradictions which I mentioned in the beginning of this chapter, these two views appear. When antivivisectionists are protesting against experiments on animals, they are inspired by sym- pathy for poor creatures which cannot defend themselves. Guided by conscience, they think immoral any suffering in- flicted upon a living being for the benefit of another being, whether human or animal. I know distinguished physio- logists who have determined to limit their experiments to animals with little sensibility, such as frogs. The great majority of scientific men, however, would have no scruple in opening bodies and subjecting their victims to severe suffering in the hope of clearing up some scientific problem which sooner or later would increase the happiness of human beings and animals. If vivisection had not been per- formed, or if it had been restricted, the great laws of infec- tious diseases would not have been discovered, nor would the discovery of many valuable remedies have been made. To justify investigation, men of science set out from the utilitarian theory of morality, which approves everything that is useful to the human race. The antivivisectionists, on 304 THE PROLONGATION OF LIFE the other hand, rely on the intuitive theory, according to which conduct is controlled by the spontaneous activity of our conscience. In the case which I have selected the problem is easy to solve. It is plain that vivisection is inevitable in the ex- perimental investigation of vital processes, as it is the only means by whch serious progress can be made. None the less, very many people cannot accept this necessity, because of the intensity of their love for animals. In the question of the prevention of syphilis, the moral problem is still more easy to settle. Whilst in the case of vivisection a real suffering may be inflicted upon animals, in preventive measures against syphilis, the evil is more or less intricate and very problematic. The certainty of safety from this disease might render extra-conjugal rela*- tions more frequent, but if we compare the evil which might come from that with the immense benefit gained in preventing so many innocent persons from becoming dis- eased, it is easy to see to which side the scale dips. The indignation of those who protest against the discovery of preventive measures can never either arrest the zeal of the investigators or hinder the use of the measures. This example again shows that reasoning is necessary in the solution of most moral questions. However, the problems which arise in actual life are often very much more complicated than the two cases I have taken as an introduction. It is easy to prove the high utility of the work of vivisectors and of those who are seeking means of preventing syphilis, whilst their adversaries have nothing to invoke but their feelings. The situation is quite different in many questions which border on morality. The sexual life abounds in extremely diffi- cult problems, in which it is almost impossible to deter- UTILITARIAN MORALITY 305 mine what is right. Let me recall the vagaries in the life of Goethe, whose great genius was so often in conflict with the morality of his time. Was he wrong in giving up Frederique and Lili from the fear that a permanent bond would damage his poetic productivity ? Then there is the moral question of the marriage of men affected with syphilis, or other diseases which might influence the off- spring. The problems of the continence of young people before marriage, of prostitution and of means of prevent- ing conception are without doubt questions of great im- portance, the solution of which is extremely difficult from the point of view of morality. Differences of opinion are revealed in nearly everything relating to punishment. The question of the death penalty is much in dispute and requires numerous investigations of different kinds. Statistics have been collected to give information as to the utility or inutility of the death penalty. According to some results, capital punishment does not diminish the number of crimes, whilst according to others it has a real preventive effect. Punishments less violent than death, and particularly the punishments of children, are equally troublesome, and schoolmasters have difficulty in finding a solution. The utilitarian theory of morality often finds it impos- sible to prove the advantage of the conduct it prescribes, and this the more because in many cases we do not exactly know who is to profit by it. Is the utility of any par- ticular act to be considered so far as it affects relatives, members of the same religion, of the same country, or of the same race, or all humanity ? In face of these difficulties, many moral philosophers have given up the utilitarian theory and declared for an intui- tive theory. The basis of morality is to be found in a 3o6 THE PitOLONGATION OF LIFE feeling innate in every man, a sort of social instinct urging liim to do good to his neighbour, and which, by the voice of his own conscience, dictates how he ought to act much more precisely than could be done by any comprehension of the utility of his conduct. It is certainly true that man is an animal living in society because of his need for association with other human beings. But whilst in the animal world the members of societies are actuated by an instinct which is blind and generally very precise, in man we find nothing of the kind. The social Instinct appears in him in endless variety. In some of us love of neighbours is extremely highly developed, so that some persons are only happy when sacrificing themselves for the public good. They give all that they have to the poor, and often die for some ideal which is necessarily altruistic. Such examples are rare. Many men, however, profess an affection for some of their kind, devote themselves to their relations, their friends, or their compatriots, and remain practically indifferent to all others. Other individuals, again, have an even narrower sphere of affection, and take advantage of their fellows, either in their own interest or in that of their own family. Still more rare are the really wicked persons who have no love for anyone but themselves and who take pleasure in doing harm to those about them. Notwithstanding this diversity in the development of the social instinct, all men have to live together. If it were possible to know the inner motives of men, these might be used as a basis for classifying conduct. Those acts might be described as moral which were in- spired by neighbourly love, and those as immoral the motive of which was egoism. But it is seldom that the real motives are discovered; they lie deep down in the UTILITARIAN MORALITY 307 individual mind, sometimes unknown even to the man him- self. We can nearly always harmonise our acts with the dictates of our consciences and find reasons for the harm we inflict upon others. It is only rare natures that possess a conscience so delicate as to be always tormented lest they are not doing good to their neighbours. In the course of life, men are disposed to attribute bad motives to their opponents. Such an attitude makes criticism easier and panders to the common wish to speak evil of one's neighbours. Notwithstanding the numerous precedents for such an attitude amongst politicians and journalists, it must be discarded from any serious study of morality. The motives and the conscience are elusive elements of little use in any attempt to value human conduct. We have to fall back on the consequences of action. Now it is easy to show that the social instinct often leads to action which is not good. It frequently happens that men, acting with the highest and best intentions, do much harm. Schopenhauer long ago pointed out that morality based on sentiment is a mere caricature of real morality. Impelled by the altruistic wish to do good, men often lavish unre- flecting charity and do harm to others and to themselves. In Timon of Athens Shakespeare depicted A most incomparable man ; breathed, as it were, To an untirable and continuatc goodness, and who gave away to' the right and the left, creating around him a cloud of parasites. He finally ruined him- self and became a hopeless misanthrope. Shakespeare put his verdict in the mouth of Flavius : — Undone by goodness. Strange, unusual blood, When man's worst sin is, he does too much good. X 2 3o8 THE PROLONGATION OF LIFE Morality, founded purely on sentiment, has inspired the attacks on vivisectors which in all confidence spread evil amongst men. It is a surprising result of the great complexity of human affairs, that society is sometimes better served by wicked acts than by acts inspired by the most generous feelings. Thus extremely rigorous measures of repression are often more successful than the half-measures employed by humane and charitable administrators. The intuitive theory of morality has had no greater suc- cess than utilitarianism. Even if the sentiment of society were a true basis of moral conduct, it fails in actual practice. On the other hand, although utility is the object of all morality, it is in most cases so difficult to determine what is really useful, that utilitarianism breaks down as the founda- tion of morality. We must look elsewhere for principles which can guide us towards right conduct. II MORALITY AND HUMAN NATURE Attempts to found morality on the laws of human nature — Kant's theory of moral obligation — Some criticisms of tHfe Kantian theory — Moral conduct must be guided by reason Even in antiquity, there were efforts to find a basis for morality other than the precepts of religion based on revela- ' tion, but the failure of such attempts has long been ad- mitted. In the first chapter of The Nature of Man, 1 described such efforts to find a basis for morality in human nature itself. The Epicureans and the Stoics, although their doctrines were opposed, each claimed to set out from human nature. The principle is too vague for practical use, as human nature can be interpreted in very different fashions. When several attempts to find a rational basis for morality had failed, Kant's theory appeared and was hailed by many as a real advance. None the less, it has not met with general approval and may be taken as a supreme instance of the failure to solve the great problem of morality by reason. I do not wish to deal with it at length, but a review of its main outlines is pertinent to my argument. According to Kant, morality cannot be founded on the feeling of sympathy, nor can it have as its object the happi- ness of men. Nature, would have been an unskilful work- 3IO THE PROLONGATION OF LIFE man were her object the happiness of human beings, for many lower animals have much more happiness. An inner law is the force compelling us to morality, and without that we should have to seek our guide in happiness. Kant's doctrine is an intuitive theory of morality. It is based neither on sympathy nor on any inherent charity, which would make us covet happiness for our fellows, but solely on the consciousness of duty. Kant thought that the action of a man who wished to do good to his fellows was devoid of merit. Conduct was moralonly in so far as it was obedience to the inner sense of duty. Schiller's epigram has thrown into relief this part of the great philo- sopher's theory, "When I take pleasure in doing good to my neighbour, I am uneasy, as I fear that I have been lacking in virtue." In his criticism of Kant's system, Herbert Spencer drew a picture of a world inhabited by men who had no sym- pathy for their fellows and who did good to them against their natural instincts and only from a pure sense of duty. Spencer thought that such a world would be uninhabitable. Clearly, moral conduct, on the Kantian basis, could be followed only by exceptional persons, for most men follow their inclinations rather than any sense of duty. People ,iof lower culture would accept kindnesses from others with- out caring whether the motive were kindness or a sense of duty, but highly civilised people would not endure service from those whom they knew to be acting against their instincts in obedience to a sense of duty. And so men would be driven to hide the real motives of their conduct, lest they should offend the sensibility of those towards whom their moral conduct was directed. Such cases, where the real motive is concealed, show how impossible it is to judge of conduct from the motives which may be supposed MORALITY AND HUMAN NATURE 311 to have inspired it. As it is generally impossible to know whether some altruistic conduct has been inspired by kind- ness or has been performed as a duty, it is better to give up any attempt to appraise the springs of moral conduct. Kant himself realised the need of some other standard for appraising human conduct. With such a purpose he arrived at his well-known maxim : — " Let your conduct be such that your motive might serve as a standard of uni- versal application." To explain the maxim he gave a number of examples. A man who is without money and cannot pay a debt is in doubt as to whether he should promise to repay his creditor. According to Kant, he ought to ask himself what would be the result if such a promise were to be made under similar circumstances by everyone. It is plain that if such false promises became universal, they would cease to be believed and so would be impracticable in actual life. Kant's formula, therefore, would supply a rational basis for the discrimination of immoral conduct. In the case of theft it would operate as follows : if it became the custom for everyone to take what- ever he wanted, private property and theft would simul- taneously cease to exist. So also suicide is immoral, since if it became general the human race would cease to exist. Kant, however, was looking at only one side of the problem. Moral conduct is frequently limited to an indi- vidual, and cannot be generalised for all humanity. Thus, for instance, if one about to sacrifice his life for the good of his fellows were to estimate his action according to Kant's formula, he would reach a conclusion similar to that in the case of suicide; if everyone were to sacrifice his life for others, no one would remain alive, and so, according to Kant, the sacrifice of one's life for the good of others would be an immoral act. 312 THE PROLONGATION OF LIFE It is plain that in his search for a rational basis of moral- ity, Kant found only a hollow form, void of any substantial body of morality. It is not enough that a moral man should take his consciousness of duty as a guide. He must know what would be the result of his acts. If it is immoral to make a false promise, it is because people would lose confidence in such promises, and confidence is necessary to our well-being. When the formula of Kant condemns theft, it is because, if theft became general, there could be no private prope'rty, and property is regarded as necessary to the well-being of men. Suicide is immoral, according to Kant, because it would lead to the disappearance of the human race, and human life is of course a good. Kant tried to found his theory of morality on a rational basis which excluded the idea of the general good, but it was impossible for him to avoid it. His " practical reason," when it raised the consciousness of duty to a principle, should have pointed the goal towards which moral acts were to be directed. In this matter, I find that Kant's ideas are very vague, although extremely interesting. The innate feeling of duty implies the will to pursue moral conduct. This will is independent of the circum- ambient conditions. Kant in his nebulous language ex- plains this consideration as follows : — " Our reason informs us of a law to which all our maxims are subject, as if, our will had created its own natural order of things. This law, then, is in the sphere of a nature which we do not know empirically but which the freedom of the will makes possible, a nature which is supra-sensible, but which from the prac- tical point of view we make objective, because it is created by our will in virtue of our existence as rational beings. The difference between the laws of a nature to which the will is subject and a nature subject to the will subsists in MORALITY AND HUMAN NATURE 313 this, that in the first the objects must be the causes which determine the will, whilst in the second, the will itself causes the objects so that the causality of the will resides exclusively in pure reason, pure reason being thus practical reason " (Critique of Practical Reason). So far as I can follow the argument of Kant, it seems to me to imply that rational morality cannot be bound by human nature as it exists. I may perhaps interpret Kant's thought as if he had the intuition that the moral will was capable of modifying nature by subjecting it to its own laws. On the other hand, several critics of Kant have attempted to improve his theory of morality by reconciling it with human nature as it actually exists. Vacherot,^ for instance, has taken such an attitude in the most definite fashion. He insists that Kant "did not appreciate the capital im- portance of the object of the moral law. The problem which under the designation summum bonum absorbed the schools of antiquity plays a minor part in the Kantian theory. Kant should have recognised that human destiny is not limited to duty but must include happiness " (p. 316). But what is this " happiness " which is to be the standard of human actions ? To answer this Vacherot places him- self in the position of those ancient philosophers whom I discussed in The Nature of Man. He makes his point absolutely clear. "What is the 'good' for any being? The attaining of its purpose. What is the purpose of a being ? The simple development of its nature. Apply this to man and morality. When human nature is known by observation and analysis, the deduction can be made as to what is the purpose, and the good, and therefore the law of man. For the conception of the good necessarily in- ' Essais de Philosophie critique, Paris, 1864. 314 THE PROLONGATION OF LIFE volves the idea of duty and of law to be imposed on the will. We have to fall back, then, on knowledge of man, but it must be complete knowledge, a recognition of the facul- ties, feelings, and inclinations that are peculiar to him and that distinguish him from animals" (p. 319). Here is a summary of this doctrine: — "Develop all our natural powers, subordinating those which are subsidiary to those which form the peculiar quality of human beings; this is the true economy of the little world we call human life; this is its purpose and this its law. The formula states in the most scientific and least doubtful form a very old truth, the foundation of all morality and the test of all its applica- tions. If we seek to know what are justice, duty and virtue, we must look in the world itself, and not above or below it" (Op. 301). Professor Paulsen, a more recent critic of Kant, comes to a similar conclusion.^ He thinks that Kant should have modified his formula in some such way as follows : — " The laws of morality are rules which might serve for a natural legislation for human life; in other words, rules that, when they guided conduct according to natural law, would result in the preservation and supreme development of human life." From whatever side we examine the problem of morality, we come to submit conduct to the laws of human, nature. Sutherland, a modern author who discusses morality by the scientific method, defines morality as " conduct guided by rational sympathy." Such sympathy would not subor- dinate the chief good of others to an advantage less impor- tant but more immediate. Tiwjs a mother may sy4npathise with her child when it has to take some unpleasant ' System der Ethik, 7th and 8th editions, vol. i, p. 199. Berlin 1906. MORALITY AND HUMAN NATURE 315 medicine ; but if her sympathy be rational she will not let it interfere with the health of the child. In the foregoing case, sympathy has to be controlled by medical knowledge. In moral conduct generally, reason must be the determining factor, whatever be the inspiring motive of the conduct, whether it come from sympathy or from the sense of duty. And thus morality in the last resort must be based on scientific knowledge. Ill INDIVIDUALISM Individual morality — History of two brothel's brought up in same circumstances, but whose conduct was quite different 1 — Late development of the sense of life — Evolution of sym- pathy — ^The sphere of egoism in moral conduct — Christian morality — Morality of Herbert Spencer — Danger of exalted altruism Although moral conduct refers specially to the relations between men, there exists a morality of the individual. As this latter is simpler, I shall consider it first in my investigation of rational morality. When a man, seeking his individual happiness, gives way to his inclinations without restraint, he often comes to behave in a way that is generally regarded as immoral. Following his inclination, he may become idle and drunken. Idleness may depend on some irregularity of the brain, and may thus be as natural as is the wish to take drink in the case of a man to whom alcohol brings a feeling of well- being and gaiety. Why is it that idleness and alcoholism are immoral ? Is it because they prevent the living of life in its completest and widest sense, according to the theory of Herbert Spencer ? But it is precisely in this way that the adherents of the theory justify all kinds of excess with- out which fullness and width of life seem to them impos- sible. INDIVIDUALISM 317 Whilst vices such as idleness and drunkenness arise directly from qualities of the human constitution, they must be regarded as immoral because they prevent the completion of the ideal cycle of human life. I knew two brothers, almost the same age, subject to the same influ- ences, and brought up in the same environment. None the less, their tastes and conduct were very different. The older brother, although very intelligent, during his college career devoted himself eagerly to bodily exercises and indulged in every way his inclination for pleasure. " As the chief end of life is happiness," he said, "one must try to get as much of it as possible," and so he got into the habit of visiting places where there was most amusement. Cards, good living, and women furnished for him the means of pleasure. As his ability was unusual, he passed his examinations almost without having worked. The example of his younger brother, always a devoted student, did not attract him. "It is all very well for you," he said, "as you find your happiness in work ; as for me, I detest books, and I am happy only when I am giving myself up to pleasure. Everyone must take his own road to the goal of life." As a result, the health of the older brother was seriously affected by his mode of life. He acquired some disease of the circulatory system, had to face the end, and died at the age of fifty-six. The last years of his life were very unhappy, as the instinct of life developed in him extremely strongly. He was a victim of his own ignorance because when he was young he did not know that the sense of life would develop later on, and would become much stronger than in his youth. His brother was equally un- aware of this fact, but, absorbed in scientific study, he kept himself apart from the indulgences of youth and lived a sober life. In this way he found that his strength and 3i8 THE PROLONGATION OF LIFE activity were fully pireserved at a time of life when his older brother was already a physical wreck. I have quoted this example, not to repeat the banal idea that a sober life is followed by a healthier old age than an intemperate life, but because I wish to insist on the import- ance of the development of the instinct of life in the course of each" individual life. I see that this idea is very little known. I was present at the last moments of my older brother (he was called Ivan Ilyitch, and he was the subject of the famous story of Tolstoi : The Death of Ivan Ilytich), Knowing that he was going to die from pyemia, at the age of forty-five, niy brother preserved his great intelli- gence in all its clearness. As I sat by his bedside he told me his reflections in the most objective fashion possible. The idea of his death was for long very terrible to him, but " as we all die " he came to " resign himself, saying that after all there was only a quantitative difference between death at the age of forty-five and later on." This reflection, which relieved the moral sufferings of my brother, is none the less untrue. The sense of life is very different at different ages, and a man who lives beyond the age of forty-five expediences many sensations which he did not know before. There is a great evolution of the mind during the advance of age. Even if we do not accept the existence of an instinct of natural death as the crown of normal life, we cannot deny that youth is only a preparatory stage and that the mind does not acquire its final development until later on. This conception should be the fundamental principle of the science of life and the guide for education and practical philosophy. Individual morality consists of conduct permitting the accomplishment of the normal cycle of life and ending in INDIVIDUALISM 319 a feeling of satisfaction as complete as possible and which can be reached only in advanced age. And so, when we see a man wasting his health and strength and youth, and thus making himself incapable of feeling the most com- plete pleasure in life, we call him immoral. A man entirely isolated does not exist in nature. We are born weak and incapable of satisfying our needs and at once come into relations with the human being who feeds us and protects us. The child, although egoistic, becomes attached to his protector, and in this way the feel- ing of sympathy is born. Guided by this feeling as well as by the sense of his own interest, the child soon begins to employ his will in restraining some of his instincts, which, none the less, are quite natural. Thus, the fear of being deprived of food makes him obedient to his protectors. The child cannot complete his normal cycle without pursu- ing a certain moral conduct. When he becomes adult, man experiences the instinctive need of relations with someone of the other sex. This need lays certain duties on him, and although the love of a young man is less egoistical than that of the child, it is far from presenting the characters of self-abnegation and sacrifice. A young woman, after having passed through the usual cycle of life with her mother and with a man, becomes herself a mother. Maternal instinct furnishes her with certain rules of conduct, but this natural instinct is not enough to fulfil its object, that is to say, to rear the child until an age when it can live independently. Directed by a feeling of sympathy for her child, the young mother learns from women with more experience to ward off dangers from her child. In the first years, moral conduct on the part of the mother consists almost entirely in bring- 320 THE PROLONGATION OF LIFE ing up the child in a healthy way. For this purpose she must acquire much knowledge. If she remains ignorant, her conduct must be regarded as immoral. So far as concerns the bringing up of a child, the moral problerh is quite simple, because we are all agreed that the object is to rear the child to maturity in the healthiest pos- sible condition. When the child exhibits any habits harmful to this object, although due to natural instincts, the mother applies her knowledge to restrain them without paying attention to the theory that happiness consists in the fulfilment of everything that is natural. When a child has passed through the perilous first period of its life, the mother has to ask what general object she is to follow in its education. She wishes her child to be as happy as possible. Here the conception of orthobiosis will serve her, and it will teach her that the greatest happiness con- sists in the normal evolution of the sense of life, leading to serene old age, and finally reaching the fulness of satiety of life. Man, who has passed his apprenticeship to life from his birth, with his protectors, and, later on, with persons of the other sex, inevitably acquires certain elements necessary for social life. Persuaded that in order to succeed in his individual life he must have help from his fellows, he learns to subdue his anti-social tendencies, at first in his own interests. Let me take an example of this. When a man has reached a certain stage of civilisa- tion, it generally becomes impossible to him to supply his bodily wants without the help of persons less cultured than himself. He takes into his house one or more servants, with whom he enters into definite relations. He wishes for himself and those about him a normal life, such as I have described in The Nature of Man. To attain this it is in- dispensable in his own interest and in that of his family, INDIVIDUALISM 321 that his domestic servants should be well treated. The health of the family very often depends on the conduct of the servants, who will follow conscientiously the hygienic rules only if they themselves are living in good conditions. The custom according to which the masters live in luxu- riously furnished rooms, while their servants have mean quarters in the attics, is immoral from the point of view of the well-being of the masters themselves. The crowded servants' quarters are a nest of all sorts of infection, which may spread in the families of the masters. Very often people who think that they are following the rules of exact hygiene contract diseases without knowing that the infec- tion has come from their servants. Anger gives us another example. It is certainly harmful to the health, and so should be controlled in the interest of the bad-tempered person himself. Fits of rage are fre- quently followed by ruptures of blood-vessels, and by diabetes, and even cataracts have developed after some violent passion. Luxurious habits are also well known to be harmful to the health. Heavy meals, evenings passed in the theatre and in society may seriously affect activity of the organs. Moreover, the luxury of some people is often the cause of misery to others. The knowledge that luxurious habits shorten life and prevent man from reaching the greatest happiness may warn people against luxury better than the appeal to the feeling of sympathy. As it is a fact that most men guide their lives generally from egoistic motives, any theory of morality which is to be put into practice must reckon seriously with this factor. All other systems have recognised it. In the Sermon on the Mount, which is a summary of Christian morality, each moral act is recognised on the ground that it will bring Y 322 THE PROLONGATION OF LIFE some reward or obviate some punishment. " Rejoice," said Jesus, "and be exceeding glad; for great is your reward in heaven" (Matt, v., 12). "Take heed that ye do not your alms before men, to be seen of them ; otherwise ye have no reward of your Father which is in heaven " (Matt, vi., i). "That thine alms may be in secret; and thy Father which seeth in secret himself shall reward thee openly" (Matt, vi., 4). "Judge not, that ye be not judged" (Matt, vii., i). "But if ye forgive not men their trespasses, neither will your Father forgive your tres- passes " (Matt, vi., 15). Jesus had no high opinion of the influence of altruism on human conduct. Herbert Spencer in his treatise on morality (The Data of Ethics) also insists that laws of conduct, to be of general application, must not require men to make too great sacrifices, as otherwise the best teaching would remain a dead letter. He imagines, however, that in the future the human race will be so much improved that moral conduct will become instinctive, needing no compulsion. The Eng- lish philosopher presents a view of the future of the human race totally at variance with the Kantian conception. Instead of human beings becoming filled with a sense of duty opposed to their natural instincts, the world will be peopled with men acting morally from inclination, so making the world delightful. The ideal is so far removed from existing conditions that the possibility of its attainment is hardly worth consider- ing. It is probable that a world whose inhabitants had the feeling of sympathy very highly developed would not be so delightful. For sympathy is generally a reaction against evil. When evil disappears, sympathy would be not merely useless, but annoying and harmful. George Eliot in Middlemarch describes a young woman INDIVIDUALISM . 323 enthusiastically anxious to do good to her fellows. When she came to live in a village, she made great plans to succour its poor. Her disillusion and annoyance were great when she found that the villagers were quite com- fortably off, and had no need of her charity. John Stuart Mill in his Autobiography relates that when he was.young he dreamed of reforming society and making everyone happy. But when he asked himself if the accom- plishment of his beautiful ideas would make him happy, he was compelled to answer "No! " and this discovery plunged the young philosopher into a lamentable condi- tion. He described himself as quite overcome, all that supported him in life crumbling away. His happiness could lie only in the constant pursuit of his object, and the charm seemed broken, because if attainment were not to please him, how could the means be of any interest to him? It seemed to him that nothing was left to which he could dedicate his life. As it is highly probable that with the advance of civilisa^ tion the greatest evils of humanity w-ill become lessened, and may even disappear, the sacrifices to be made will also become less. Now that there is a serum which protects agairt'st plague, there is no room for the heroism of the doctors who used to incur the greatest danger in fighting epidemics. Until lately doctors used to risk their life in treating the throats of diphtheric patients. A young doctor who was a friend of mine, of high ability and promise, died from diphtheria contracted under these conditions. He met his death, in isolation from his friends in case of infect- ing them, with the utmost heroism. Now that the anti- diphtheric serum has been discovered, such heroism would be unnecessary. The advance of science has removed the occasion of such sacrifices. Y 2 324 THE PROLONGATION OF LIFE It is now very long since there has been opportunity for the heroism which steeled the hand of Abraham to sacri- fice his only son to his religion. Human sacrifice, based on the highest morality, has become more and more rare, and will finally disappear. Rational morality, although it may admire such conduct, has no use for it. So also, it may foresee a time when men will be so highly developed that instead of being delighted to take advantage of the sym- pathy of their fellows, they will refuse it absolutely. Neither the Kantian idea of virtue, doing good as a pure duty, ncr that of Herbert Spencer, according to which men have ah instinctive need to help their fellows, will be realised in the future. The ideal will rather be that of men who will be self-sufficient and who will no longer permit others to do them good. IV ORTHOBIOSIS Human nature must be modified according to an ideal — Comparison with the modification of the constitution of plants and of animals — Schlanstedt rye — Burbank's plants— The ideal of orthobiosis — ^The immorality of ignor- ance-7-The place of hygiene in the social life — The place of altruism in moral conduct — ^The freedom of the theory of orthobiosis from metaphysics As I have shown in The Nature of Man, the human con- stitution as it exists to-day, being the result of a long evolution and containing a large animal element, cannot furnish the basis of rational morality. The conception which has come down from antiquity to modern times, of a harmonious activity of all the organs, is no longer appro- priate to mankind. Organs which are in course of atrophy must not be reawakened, and many natural characters which perhaps were useful in the case of animals must be made to disappear in men. Human nature, which, like the constitutions of other organisms, is subject to evolution, must be modified accord- ing to a definite ideal. Just as a gardener or stock raiser is not content with the existing nature of the plants and animals with which he is occupied, but modifies them to suit his purposes, so also the scientific philosopher must not think of existing human nature as immutable, but must try to modify it for the advantage of mankind. 326 THE PROLONGATION OF LIFE As bread is the chief article in human food, attempts to improve cereals have been made for a very long time. Rimpau made one of the greatest steps in this direction when he introduced into cultivation a variety of rye known as Schlanstedt rye, now fairly abundant in France and Germany. Rimpau set himself the task of producing a variety with the longest ears and containing many and heavy grains. Having conceived his ideal, he began to seek out what was nearest to it in a very large number of examples of rye. After patient and continued labour, using careful selection and cross-fertilisation, Rimpau succeeded in making the new variety, and so did a great service to mankind. Burbank,^ an American horticulturist, has recently gained a wide reputation because of his improvements of useful plants. He has produced a new kind of potato which has raised the value of potato crops in the United States by about ;^3, 500,000 per annum. Burbank cultivated great numbers of fruit trees, flowers, and all kinds of plants, with the object of increasing their utility. One of his objects was to produce varieties which coi^ld resist dry conditions, which reproduced rapidly and so forth. He has modified the nature of plants to such an extent that he has cactus plants and brambles without thorns. The succulent leaves of the former provide an excellent food for cattle, whilst the absence of thorns in the latter makes their pleasant fruit more suitable for gardens. Burbank has enormously improved the production of stoneless plums, and has very much reduced the price of many bulbs and lilies by increasing their productivity. To obtain such results much knowledge and a long period of time wgre necessary. To modify the^ nature of ' De Vries, in Biologisches Centralblalt, 1906, Sept. ist, p. 609. ORTHOBIOSIS 327 plants it was necessary to understand them well. To frame the new ideal of the plant it was necessary not only to have an exact conception of what was wanted, but to find out if the qualities of the plants in question furnished any hope of realising it. The methods which have been successful in the case of plants and animals must be much modified for application to the human race. In the case of human beings the selec- tion and cross-breeding which were imposed upon rye and plum trees are not possible, but, at the same time, the ideal of human nature, towards which mankind ought to press, may be formed. In our opinion this ideal is ortho- biosis, that is to say, the development of the human life so that it passes through a long period of old age in active and vigorous health, leading to the final period in which there shall be present a sense , of satiety of life, and a wish for death. I do not think that the ideal should be th^t of Herbert Spencer, a simple prolongation of hum^n life. When the instinct of death comes at a not very late period of life, there would be no inconvenience in shorten- ing the life, if death did not come soon after the appear- ance of the instinct. Probably this would be the only case where suicide was justified in the conception of orthobiosis. The foregoing is the case of an action in conformity with the ideal, but quite contrary to human nature as it js at present. A similar contradiction appears in reproduc- tion. Man came from animals amongst which unliniited reproduction was an important factor in the preser- vation of the species, as it allowed the species to survive upc^er all sorts of bad conditions, such as diseases, com- bats, attacks of enemies, and changes of climate. Although man, according to the laws of human nature, is capable of reprocjucing extremely rapidly, the ideal of his happiness 328 THE PROLONGATION OF LIFE makes a restriction of this power necessary. Thus ortho- biosis, based upon knowledge of human nature, would set limits to a function which is perhaps the most natural of all. The restriction which is already partially adopted will come more and more into operation as the struggle against diseases', the prolongation of human life, and the suppression of war make progress. It will be one of the chief means of diminishing the most brutal forms of the struggle for existence, and of increasing moral conduct amongst mankind. Just as Rimpau began to study the nature of plants before trying to realise his ideal, so also varied and pro- found knowledge is the first requisite fof the ideal of moral conduct. It is necessary not only to know the structure and function of the human organism, but to have exact ideas on human life as it is in society. Scientific know- ledge is so indispensable for moral conduct that ignorance must be placed among the most immoral acts. A mother who rears her child in defiance of good hygiene; from want of knowledge, is acting immorally towards her offspring, notwithstanding her feeling of sympathy. And this also is true of a Government which remains in ignorance of the laws which regulate human life and human society. It must be well understood that I am not here thinking of written knowledge, set down in treatises and volumes. Rimpau and Burbank went outside manuals of botany to obtain their knowledge. Besides books, wide ideas on the practice of life are required to direct aright the conduct of men. A doctor who has just finished his studies at the hospital, notwithstanding all his knowledge, is not yet suffi- ciently trained to be a good practitioner. He must acquire the habit of treating patients, and for this years are re- quired. So also is it with regard to the practical applica- ORTHOBIOSIS 329 tions of the principles of morality. The regulation of conduct requires profound knowledge both theoretical and practical, and men selected to frame or to apply laws of morality must have this double qualification. If the human race come to adopt the principles of orthobiosis, a consider- able change in the qualities of men of different ages will follow. Old age will be postponed so much that men of from sixty to seventy years of age will retain their vigour, and will not require to ask assistance in the fashion now necessary. On the other hand, young men of twenty-one years of age will no longer be thought mature or ready to fulfil functions so difficult as taking a share in public affairs. Tiie view which I set forth in The Nature of Man regard- ing the danger whicTi comes from the present interference of young men in political affairs has since then been confirmed in the most striking fashion. It is easily intelligible that in the new conditions such modern idols as universal suffrage, public opinion, and the referendum, in which the ignorant masses are called on to decide questions which demand varied and profound know- ledge, will last no longer than the old idols. The progress of human knowledge will bring about the replacement of such institutions by others, in which applied morality will be controlled by the really competent persons. I permit myself to suppose that in these times, scientific training will be much more general than it is just now, and that it will occupy the place which it deserves in education and in life. It is equally clear that if a mother is to act morally with regard to her child, she must teach herself properly. In place of mythology and literature, she must learn hygiene and all that relates to the rational rearing of children. So, also, in the education of men, the study of the exact 330 THE PROLONQATION OF LIFE sciences must occupy by far the most important place. Then only will moral conduct and scientific knowledge begin to unite. An ignorant mother will bring up a child very badly notwithstanding all her good will and her affec- tion. A doctor, however imbued with strong sympathy for his patients, could do them much harm if he had not the appropriate knowledge. Are not politicians open to the reproach from the point of view of morality that very often through ignorance they do the very worst evil in public administration ? With the progress of knowledge, moral conduct and useful conduct will become more and more closely identified. I have been reproached because in my system the health of the body occupies too large a place. It cannot be other- wise, because health certainly plays the chief part in exist- ence. Notwithstanding his pessimism, Schopenhauer was convinced that health was the greatest treasure, a treasure before which everything else yielded. In many religions care of the health is laid down amongst the chief duties. Although many scientific men do not hold the opinion that circumcision was ordained for hygienic reasons, it is certain that hygiene was ej^tremely important in the Jewish religion. It is only in Christianity, which despises the human body, that hygiene is excluded from the re- ligious code, as in the words of Jesus : — "Take no thought for your life, what ye shall eat, or what ye shall drink ; nor yet for your body, what ye shall put on. Is not the life more than meat, and the body than raiment?" (Matt, vi., 25). As for long ages hygiene was very imperfectly known, it is not surprising that it played a small part in human affairs. Probably the objection to the importance that I assign to it in ortho- biosis is a relic from the old order of things. Now, hoAV- ORTHOBIOSIS 331 ever, the situation is different. Bacteriology has placed hygiene on a scientific foundation, so that the latter is now one of the exact sciences. It has now become necessary to give it the chief place in applied morality as it is the branch of knowledge that teaches how men ought to live. It has been objected that I have left no place for altruism in my system.^ Certainly I have tried to find an egoistic basis for moral conduct, as I have shown above. I think, however, that the wish to live according to the ideal of orthobiosis and to make others live a normal life would be a powerful agency in improving social life, in preventing mutual damage, and promoting mutual help. Such a motive, within the reach of persons whose altruistic feel- ings are not specially strong, must largely extend moral conduct amongst human beings, and even although in future such manifestations of high morality as the sacrifice of life and health will become wholly or nearly wholly useless, I think that for the present there is still room for altruism. The practical application of scientific knowledge already gained admits much self-denial and good feeling. Struggle against prejudices of all kinds and the develop- ment and diffusion of sound ideas require a conduct very highly altruistic. The fears of my opponents are still less justified when we reflect that the feelings of sympathy and of cohesion must play a large part in the business of helping the evolution of man towards the goal of normal life. Although our actual knowledge already provides a basis of rational morality, it may be admitted that in the future, if science continues its forward march, the rules of moral conduct will become still more improved. There will ' Dr. Grasset, "La fin de la vie'' in the Revue de philosophie, Aug. 1st, 1903. 332 THE PROLONGATION OF LIFE be no ground for reproaching me for a blind faith in the all-powerfulness of science. Much more trust can be given to one who has faithfully carried out his promises, than to one who has promised much and fulfilled nothing. Science has already justified the hopes which have been placed in it. It has saved people from the most terrible diseases, and has made life much easier. On the other hand, religions, which demand an uncritical faith as the means of curing the ills which afflict humanity, have not fulfilled their promises. The reproach that I preach blind faith in the progress of science, destined to replace religiofls faith, is unjust, because my faith depends on a confidence that science has already deserved. Equally unjust is the reproach that I have built my system on a partly metaphysical principle. Accord^ ing to M. Parodi,^ the hypothesis of physiological old age and of natural death seem to " involve the idea of a natural duration of human life, which, however, from accidental reasons man does not complete at present. M. Metchnikoff repeatedly uses the expression ' normal cycle.' Now do we not see here the surreptitious repetition of the old teleo- logical conception of nature, although at first he so ener- getically disavowed it ? It is the belief that the species is a necessary reality, corresponding to a definite type of its own, in fact a special design of nature ; that nature, to guide herself, had an ideal which circumstances could mistake or degrade, but which had to be restored, to its perfect form ? Otherwise, why does he insist that there must be a condition of perfect and stable equilibrium between individual and environment ? that there is a normal cycle and that it must be possible to harmonise the dis- harmonies?" I can show easily that afl these objections rest upon a ' "Morale et biologic," Revue fhilosophique, 1904, vol. Iviii, p. 125. ORTHOBIOSIS 333 simple misunderstanding. I have never conceived of the' existence of any ideal of nature or of the inevitable neces- sity of transforming disharmonies to harmonies. I have no knowledge of the " designs " and " motives " of nature ; ■ 1 have never taken my stand on metaphysical ground. I have not the remotest idea if nature has any ideal' and if the appearance of man on the earth were a part of such an ideal. What I have spoken of is the ideal of man corre- sponding to the need to ward off the great evils of old age as it is now, and of death as we see it around us. I have said, moreover, that human nature, that collection of com- plex features of multiple origin, contains certain elements which may be used to modify it according to our human ideal. I have done nothing but what the horticulturist does when he finds in the nature of plants elements which suggest to him to try and make new and improved races. Just as the constitution of some plum trees contains elements which make it possible to produce plums without stones which are pleasanter to eat, so also in our own nature there exist characters which make it possible to transform our disharmonious nature into a harmonious one, in accord- ance with our ideal, and able to bring us happiness. I have not the smallest idea what ideal nature may have on the subject of plums, but I know very well that man has such designs and such an ideal as form a point of de- .D parture for the transformation of the nature of plums. Substitute man for the plum tree and you are at my point of view. When I have spoken of the normal cycle of life or of physiological old age, I have used the words normal and physiological only in relation to our ideal of the human constitution. I might just as well have said that a cactus without thorns is the normal cactus in the conditions where it was desired to obtain a succulent plant useful as 334 THE PROLONGATION OF LIFE food for cattle. The words "normal" and "physio- logical " seemed to me more convenient than such a phrase as "in correspondence with human ideals." I ain so little convinced of the existence of any dis- position of nature to transform our ills into goods, and our disharmonies into harmonies, that it would not surprise me if such an ideal were never reached. Even in unmeta- physical circles it is said that nature has tlje intention of preserving the species at the expense of the individual. The ground of this is that the species survives the individual . On the other hand, very many species have completely disap- peared. Amongst these species were animals very highly organised, such as some anthropoid apes (Dryopithecus, etc.). As nature has not spared these, how can we be certain that she is not ready to deal with the human race in the same way. It is impossible for us to know the un- known, its plans and motives. We must leave nature on one side and concern ourselves with what is more congru- ous with oiir intelligence. Our intelligence informs us that man is capable of much, and for this reason we hope that he may be able to modify his own nature and transform his disharmonies into har- monies. It is only human will that can attain this ideal. INDEX Abelard, 273 Abraham, use of soured milk, 171 Ackermann, Mde., 237 Actinosphcerium, degeneration in, 14 Adanson, on age of Baobab-tree, 98 Adrenaline, effect of, 121 Agave, duration of life of, 100 Aged, treatment of in uncivilised countries, i, 2 Alcohol and longevity, 91, 92 Algeria, ostriches at, 76, 78, 79 Altruism, 331 Ambard, Dr., on Mde. Robineau, 7 Anaemia, of brain, and sleep, 122 use of serums in, 149 Andri, M., use of serums in anaemia, 149 Anger, 32 1 Annandale, Nelson, on age of ane- mones, 48 Annuals, change to biennials or perennials, 100 death of, 102 Antelopes, excreta of, 66 Anthropoids, mental characters of, 191 et seq. ■■ Antiseptics, use of, in intestinal putrefaction, 156 Ants, 220, 221 Apes, anthropoid, mental characters of, igi et seq. relationship to man, 184, 185 Arabs, use of milk by, 174 Aristotle, 132 Arteries, sclerosis of, in the aged, 3; Ascidians, social, 219 Ashworth, Mr., on age of anemones, .'^^ Atheroma, in the aged, 30 Atrophy, of cells, 26 of muscles, 28 Auditory apparatus, rudimentary organism, 188 Augsburg, elixir of life, 138 Auto-intoxication, from intestinal putrefaction, 69 in plants, 107 sleep, due to, 120 Babinsky, Dr., hysteria a relic from apes, 209 Balkan States, centenarians fre- quent in, 90 Baobab-tree, age of, 98 Barth, Dr., definition of somnam- bulism, 206 Batrachia, longevity of, 50 Bats, intestinal flora of, 80, 81 Bees, 49, 220, 226 Beetroot, perennial variety of, 100 Belgium, old age pensions, 4 B^lonovsky, M., on serums in antemia, 148 B^lonowsky, Dr., on Bulgarian bacillus, 170 Berthelot, on dragon-tree of Oro- tava, 96 Bertrand, M. G., on sorbose fer- mentation, 106 Bertrand and Wcisweiler, on Bacil- lus bulgaris, 179 Besredka, M., on blood serums, 148, 149 Bielschowsky, biographer of Goethe, 269 Blanchard, E., on age of carp, 50 Birds, intestinal flora of, 76, 79 longevity of, 52 Blindness, 248, 257 Bloch, Dr. I., on Schopenhauer, 247 336 INDEX Blood-vessels, hardening of, in the old, 31 Bodio, on infant mortality, 85 Boerhave, on gerokomy, 136 Bones, degeneration of, 29, 30 Bordet, M. J. M., on serums, 148 Botulism, poison of, 70, 82 Bouchard, M., on disinfection of intestines, 156 Bouchet, M., on constipation aftet parturition, 68 BourneviUe, M., on effects of extir- pation of thyroid, 34 Boveri, M., produced atherana by nicotine, 32 Bone, marrow, in old age, 37 Botryllus, 219 Boutroux, definition of morality, 303 Bradyfagy, 159 Brain, ansemia of, as cause of sleep, 122 Brehm, on age of cattle, 55 Brettes, criticism of " rudimentary organs," 186 Bricon, M., on effects of extirpa- tion of thyroid, 34 Brigand, Calabrian, fear of death, i<)4. 19s Brillat-Savarin, quotation from, 126 Brown-S^quard, specific for long life, 139, 277 Brudzinsky, M., on use of lactic microbes, 181 Buddha, on pessimism, 233, 247 Buehler, Dr., on cause of old age, 16 Buffon, on duration of life, 40, 5° Bulgarian bacillus, 178, 179, 180, iSi, 182 Bunge, on relation between growth and longevity, 42 Burbank, American horticulturist, 326, 3a8 Butterflies, longevity of, $y Biitschli, O., on life of cells, 15 Byron, 239, 247, 295 Cachexia, after extirpation of thyroid gland, 34 Caeca, of vertebrates *«. 60 et seq. Cagliostro, elixir of life, 138 Calomel, as an intestinal antiseptic, 158 and syphilis, 146 Camphor, as an intestinal anti- septic, 156 Canary Islands, 96 Cancalon, Dr., on instinct of death, 128, 129 Cancer, and cleanliness, 144 Candolle, A. de, on cypresses of Mexico, 98 on age of trees, 99 Cantacuz^ne, M., on blood serums 148 Capital punishment, 305 Carlyle, on " Werther, " 265 Castration, effects of, 272 Cats, longevity of, 56 Cattle, longevity of, 55 Celibacy, and education of women, 224 Cell reproduction, rate of, 16 Centenarians, 4, 5, 86, 88, 89, 175, 176 Charcot, on sterilised food, 162, 163 on hysteria, 202 Charron, M., on putrefactive poisons, 69 Chemin, M., on centenarians, 88, 89 Chimpanzee, 185, 192, 193 China, Emperor Chi-Hoang-Ti and immortality, 137 Chopin, a degenerate, 134 Christian morality, 321, 330 Chromophags, action of, 25 Claparide, E., on theory of sleep, 123, 124, 125 Cleanliness, and increase of life, 144 Clergymen, increasing duration of life of, 142 Coffee and longevity, 92 Cohausen, on gerokomy, 137 Cohendy, Dr. M., on Bulgarian bacillus, 178 on intestinal flora, 78, 79 on intestinal putrefaction, 168 on thymol as a disinfectant, 157 Collectivism, 228 Colon, absorption in, 64 Constipation, evil results of, 67, 68, 69 Cooking, effect of, on microbes in food, 162 Copenhagen, suicide in, 3 Coral polyps, 2 16 Cornaro, 91 Cossacks, and biennial rye, 100 Cretinism, compared with senility, 32 Croesus, 197 Cryptogams, life of, 99 INDEX 2,2>7 Cursorial birds, intestinal flora of, 76 Cypress, age of, 98 Czerny, M., on absorption in colon, 64 on cancer, 144 D 'Alton, and Goethe, 280 Dalyell, old anemone of, 48 Dana, on monstrilla, 115 Darwin, on fear, 195 David, King, 136 Death, instinct of, 128, 129 natural, 94, 109, 119 sensations at approach of, 126, 127, 130 Debreuil, Ch., on defecation in rheas, 76 on excreta of antelopes, 66 Degenerates, famous, 134 Delage, Yves, criticism of instinct of death, 128 on function of large intestines, 6s, 66 Demange, M., on old age, 119 Denmark, suicide in, 3, 237 Descent of man, 184 Despotism, and socialism, 230 de Vries, H., on duration of life of plants, 104 on prolongation of life of plants, 100 on natural death in plants, loi Diet and longevity, 46 Digestive system and senility, 59 Diplogaster, mother killed by larvse, 1 1 1 Diphtheria, 323 Disease, and shortening of life, 14S et seq. Doctors, lady, 225 Dodo, 213 Dogs, longevity of, 55 Dostoiewsky, quotation from, 2 Doyen, M., operation on double monsters, 216 Dragon-tree, of Orotava, 96, 97, 98 Drakenberg, age of, 87 Drunkenness, and morality, 317 Dryopithecus, 334 Ducks, old, II Duering, on pessimism, 248 Durand-Fardel, M., on atheroma, 30 Duration of life, in animals, 39 et seq., 133 Eagles, intestinal flora of, 82 Ecclesiastes, quotation from, 233 Eckermann, narrative of Goethe's last years, 271, 274, 279 Egoism, 227, 306, 331 "Egyptian milk, 105 Eimer, Th., on intestines of bats &c., 62, 63 Einhorn, Dr., on bradyfagy, 159 Elective Affinities, Goethe's, 273 Elephants, 9, 54, 83, 197 Eliot, George, 322 Elixir vitce, 138 Ellenberger, on digestion in horse, 78 Enriquez, on infusoria, 13 Ephemeridae, duration of life of, 113, Ii8 Epicureans, 309 Epiphyses of bones, as giving period of growth, 40 Ermenghem, van, on botulism, 70 Errera, Dr., on cause of sleep, 121 Eudoxia, 218 Ewald, on absorption in colon, 64 Exhaustion, as cause of plant death, 104, 107 Extinction of animals, 213 Eye, in old age, 36 Fatigue, Weichardt on cause of, 123 " Faust " and Goethe, 283 et seq. Favorsky, Dr., on botulism, 82 Fear, analysis of, 194 Fecundity and duration of life, 43, ^44. 4S. 57. 58 Feinkind, case of somnambulism quoted from, 204 Femininist movement, 224 Fermentation, cause of, 105 Fertility and longevity, 44, 45 Fish, longevity of, 50 Flamans, M., 5 Fletcher, on chewing, 159 Flora, of intestines, poisonous effect of, 70, 73 et seq., 151 et seq. Flourens, on duration of life, 40, 84 Fo^, on use of soured milk in Africa, 172 Food, evil eifects of putrefaction in, 163 Fouard, M., on soured milk, 180 Fiirbbinger, on Brown-S^quard's emulsions, 139 Z 338 INDEX Gautier, A., oti leucomaines, 121 Gegenbaur, on intestinal tract, 60, 61 Genius and sexual power, 272 Gerolcomy, 136 Gessner, on age of pike, 50 Gestation arid longevity, 42 Giacomini, on Harderian gland, i8g Gibbons, 192, 198 Goebel, on duration of life of prothalli, loi, 102 Goethe, 260-300, 305 " Goose-skin," 196 Gorilla, strength of, 192 Griesbach, on sense of touch in blind, 257 Glrigoroff, on Bulgarian yaHourth, ^>7S. '78 Grindon, on age of sheep, 55 Guirion, Dr., on a case of hysteria, 203 Gurney, J. H., on longevity of birds, 51, 79 HaSckel, on ittedical selection, 134 Haffkine, M., 112 Hair, 17, 18 Halictus, a solitary bee, 226 Haller, on human longevity, 84, 132 Hamlet, quotation froril, 239 Hannibal, his elephants swim the Rhone, 197 Harderian gland, 189 ' Hartmann, 235, 241 HarvSy, oh Parr, 87 Hayem, Prof., on use of lactic acid, 169, 173 Heart, diseases of, arid syphilis, MS. 146 Hegesias, and suicide, 234 Heile, on absorption in colon, 64 Heim, on microbes in milk, 176 Heim, Prof., on Alpine accidents, 130 Heine, 236, 240 HermippUs, and gerokomy, 137 Herter, Dr., experiments on Ilactic acid in dogs, 167 Hertwig, R., on Actinospheerium, 14 Hildebrand, on duration of life of piaiits, loi, 102 Hippocrates, 132 Hofriieister, on digestion in horse, Honey-ant, 222 Horse, caecum, 6j digestion, 74 use of serum, 147 Hdrsley, Sir V., on effects of ex- tirpation of thyroid, 34 Horst, on a somnambulistic soldier, 203 Hufeland, quotation from " Macro- biotique, " 137 Hugo, v., and sexuality, 277 Humboldt, on dragon-tree of Ol'o- tava, 96 on longevity of parrots, 52 Hunger, compared with sleep, 125 Huxley, on character of Otang, 193 Hygiene, and old age, 141, 142, 143 Hypnotism, of a Crowd On indi- viduals, 210 Hysteria, analysis of, 200 et ieq, in monkeys, 208 Ibsen, arid sexuality, 277 Idleness, 316 Immortality, Chiriese beverage for, 137. 138 Incubation, duration of, compared with longevity, 41, 42 India,, government of, and age of elephants, 54 Individualism, 316 Individuality, 212 et seq. Infusoria, death of, 95 senescence of, 13 Insects, ages of, 49 social, 220 et seq. Instinct, of death, 128, 129 maternal, 319, 320, ' 329 social, 306 Intestine, large, 59, 65, 67, 151 Intuitive theory of morality, 305 Jacodson, organ of, 187 Javal, Dr., on characters of the - blind, 2-57, 259 Jenner, effect of vaccination on mortality rate, 144 Josu£, M., artificial production of atheroriia, 32 Jousset, Dr., on difference between man and apes, 184 Kant, 309, 310 Kautsky, on Socialism, 229, 230 Kentigern, age of, 87 INDEX 339 Kephir, 171, 172, 173 Khoury, M., on ferment of Egyp- tian milk, 105 Kocher, Dr., on effects of extirpa- tion of thyroid gland, 33 Kocher, Prof., case of removal of large intestine, 152, '53 KoUiker, on degeneration of muscles, 27 Koppenfels, on character of gorilla, 194 Koumiss, 172 Kowalevsky, Sophie, 225 Kowalevsky, analysis of pessimism, 24'. 255 . . . .. , Kukula, experiments on mtestmal poisons, 69, 70 Kwass, 166 Lactic bacilli, and putrefaction in intestine, 168 Laignel-Lavastine, M., criticism of neuronophagy, 20 Lankester, Sir E. Ray, on lon- gevity, 12, 56 Lao-Ts^, and immortality, 137 Laud, Archbishop, old tortoise of, 5' ... Lautschenberger, on absorption in colon, 64 Lavater, Goethe's letter to, 268 Laws aiding the aged, 3, 4 " Leben," Egyptian, 105, 171, 177, 178 Le Bon, G., on hysteria in crowds, 209 Lenau, M., 236 Lenth^ric, on elephants swimming, 197 Leopardi, G., pessimistic poet, 235, 236, 247 Le Play, M., on putrefactive • ' ' poisons, 69 L^ri, M., on senile brain, 20 Lermontoff,. 236 Leucomaines, as cause of sleep, 121 Levaillant, on longevity of parrots, 52 Lewes, G. H., on Goethe, 273, 290, 29^. 298 Lexis, on duration of human life. Life, duration of, in animals, 39 et seq. Life, prolongation of human, 132, et seq. " sense " of, 260 Lima, Dr., on use of soured milk in Africa, 172, 174 Lloyd, M., old anemone of, 47 London Zoological Gardens, 51, 81 Longevity, in animal kingdom, 47 et seq. human, 84 et seq. rules for, 141 in sexes, 44 theories of, 39 Lorand, Dr., on ductless glands, 32 Love, Goethe and, 272 Loewenberg, Dr., on Mde. Robin- eau, 7 Luxury, 321 Macfadyen, Nencki and Mde. Sieber, on digestion, 153, 161 Macrophags, 25, 147 Mailaender, 235, 255 Malaquin, M., on Monstrilla, 116, 117 Male rotifers, death of, 114, 115 Malthus, theory of, 214 Mammals, longevity of, S3 Mammary glands, in males, 186 Man, compared with apes, 184, 185 natural death of, 119 et seq. longevity of, 84 et seq. Manouflfian, M., on neuronophagy, 21, 22 Marinesco, M., on neuronophogs, 19 Marrow of the bones, in old age, 37 Marsiliaceae, duration of life of prothallus, 99 Martin, on Gibbons, 192 Massart, on cause of death in plants, 102, 109 Massol, Prof., 178 Mastication, and intestinal putre- faction, 160 Matchinsky, M., on atrophy of ovary, 26 Maternal instinct, 319, 320 Mauclaire, M., operations on large intestine, 153, i.';4, 155 Maumus, M., on digestion in caeca, 61 Mauritius, giant tortoise from, 12 Maupas, M., on infusoria, 13 Maya, 178 Mayers, on Chinese -elixir, 138 Meconium, appearance of microbes in, 161 340 INDEX Medical selection, 134 Mesnet and Mottet, Drs., cases ol hysteria, 203 Mice, duration of life, 41, 43, 56 Michaelis, on muscles of monkeys, •85 Microbes, as cause of senility, 73 in food, 162, 163 passage through intestinal walls, 71 Middlemarch, G. Eliot's, 322 Milk, importance of boiling, 177, 178 microbes of disease in, 177 putrefaction and fermentation of, 167 use of soured milk, 181, 182 Mill, J. S., 323 Milne-Edwards, H., on laws of duration of life, 42 Minot, Prof., on cause of old age, 16 Moa, 213 Moebius, on Goethe, 271 on Schopenhauer, 255 Molluscs, ages of, 48 Mongols, hair in old, 17 Monkeys, longevity of, 83 Monsters, double, 216 Monslrilla, life-history of, 115, n6, 117 Montefiore, Sir M., 91 Morality, Christian, 321 definitions of, 303 Kantian, 309, 310, 311, 312 science and, 301 et seq. Mortality rates of old persons, 142, 143 Moses, use of soured milk, 171 Mosso, on fear, 194, 196 Muscles, degeneration of, 9, 26, 27 Myxomycetes, 215 Naegeli, on age of trees, 99 Nails, growth of, in the old, 18 Naphthaline, as an intestinal anti- septic, 156 Nature, human, 325 Nausenne, Mde., cause of longevity, 141 Negroes, longevity of, 88 Neisser, Prof., on protection against syphilis, 146 Nematodes, death of, iii Nemertines, life-history of Pilidium of. loQ ft sea Nencki and Sieber, on digestion, IS3. 161, 169 Neuronophags, 19, 20, 21, 22, 23, 24 Nicotine, use of in experimenlal production of atheroma, 32 Nietzsche, criticism of Socialism, 230 Nogueira, M., on use of soured milk in Africa, 172, 174 Obstacles, sense of, 258 Old age, Goethe and, 279 et seq. Olympian, .Goethe as an, 269 Optimism, foundation of, 256 Goethe's transformation to, 269, 270 et seq. Orang-outan, 185, 193 Orotava, dragon-tree of, 96 Orstein, Dr., on centenarians in Greece, 90 Orthobiosis, 212, 325 et seq. Ossetes, use of soured milk, 173 Osteoclasts, 30 Ostrich, defecation of, 76 Oustalet, M., on longevity of verte- brates, 46 Ovary, atrophy of, 26 Owls, intestinal flora of, 83 Ownership, collective, 229, 230 Parodi, on old age, 332 Parr, Thomas, 87 Parrots, duration of life, 41 scanty intestinal flora of, 79 Pasquier, Dr. du, on constipation, 67 Pasteur, discovery of lactic microbe, los, 167 Paulsen, criticism of Kant, 314 Pensions, old age, 3, 4, 133 Pessimism, 129, 233, 234, 239, 241, 249, 266 Pessimist, study of life-history of a, 249 et seq. Pfliiger, on longevity, 93 Phagocytes, 18, 19 Phagocytosis, examples of, 25, 37 Phalansteries, 229 Pilidium, 109 et seq. Pitres, M., hysteric patients of, 200 Plague, 323 Plants, death of, 99, 103 Plasmodia, of Myxomycetes, 215, 216 Pleurotrocha haffkini, 112, 113 Pochon, Dr., experiments on use of lactic bacilli, 169 Poehl. Dr., on spermine, 139, 140 Pohl, Dr., on growth of hair, 17, 18 Ponogenes, as cause of sleep, 120 INDEX 341 Potatoes, improved by Burbank, 326 Poushkin, 236 Predestination, and plants, 103 Preyer, Dr., on Ponogenes, 120 Prichard, on longevity of negroes, 88 Productivity compared with fecund- ity, 57. 58 Prostokwacha, 172, 176 Prolongation of life, 132 et seq. . Prothalli, life of, 99 Psychids, death of, 117 Ptolemy, fear of Hegesias' philo- sophy, 23s Punishment, capital, 305 Purgatives, use of, in intestinal putrefaction, 157 Putrefaction, intestinal, 151 et seq., 161, 163, 164 QtjfiTELET, on stature of the aged, 9 Rabbit, fecundity of, 58 Ravens, absence of putrefaction in intestines of, 75 Reagents, action of, in distorting tissues, 20 Renouvier, C, on his own death, 127 Reproduction, organs of, rudiments in, 189 Reptiles, longevity of, 50 Rhea, caeca of, 60, 77 Rhinoceros, longevity of, 54 Ehytina, 213 Riley, James, on food of Arabs, 174 Rimpau, on cultivation of rye, 326, 328 Rist and Khoury, on milk, 178 Rist, M., on ferment of Egyptian milk, 105 Riviire, M., on defecation in ostriches, 76, 78, 79 Robineau, Mde., 5, 6, 7, 8, 128, 159 " Roman Elegies," Goethe's, 268, 273 Rotifera, duration of life, 39 death of, 112 Roux, anti-syphilitic ointment, 146 Rovighi, on Kephir, 173 Rudimentary organs, 185 et seq. Rye, duration of life of, 100 Rimpau 's improvement of, 326 Salp^triire, hysterical patients at, 201 old women in the, 4, 5 Sand, M., on senile brain, 20 Sargent, on age of Sequoia, 98 Sauer-kraut, 165, 171 Sauvage, M., on atheroma, 30 Savage, on character of anthro- poids, 193 Saxe-Weimar, Grand Duke of, and Goethe, 274 Schaudinn, spirillum of syphilis, 31 Schiller, Goethe on, 271 Schiller, on moral conduct, 310 Schlanstedt, rye of, 326 Schmidt, on microbes in constipa- tion, 70 Schopenhauer, 235, 247, 255, 277, 330 Schumann, a degenerate, 134 Science, and morality, 301 et seq. Sclerosis, in the aged, 31 Sea-anemones, longevity of, 47, 48 Sea-cow, 213 Selection, medical, 134 Seneca, 132, 235 Senescence, Brown-S^quard's speci- fic against, 139 mechanism of, 25 phagocytosis as cause of, 35 Senility, characters of, 8, 14 and digestive system, 59 theories of causation of, 15 et seq. Sensation, analysis of, with regard to pain and pleasure, 243 Sense of life, 26 of obstacles, 258 Sense, organs of, rudimentary structures in, 186, 187 "Sermon on the Mount," 321 Serums, cytotoxic, 147, 148, 149 Servants, care of, 321 Sex, and longevity, S7 Sexuality, Goethe and, 273 et seq. and old age, 276 moral problems of, 305 Sexual organs, abnormalities of, 224 Sexual power and genius, 272 Shakespeare, quotations, 239, 307 Sheep, digestion of, 74 longevity, 55 Sight, rudimentary organs of, 189 Silos, i6s Siphonophora, 217 Skeleton, atrophy of, in the aged, 29 Sleep, and anaemia of brain, 122 and auto-intoxication, 120 and death compared, 125 342 INDEX Sleepiness, compared with hunger, Sleeping-sickness, 124 Small-pox, and mortality rates, 144 Smell, analysis of, 243 Smell, rudimentary organs of sense of, 187 Smoking and longevity, 93 Social animals, 214, 220 et seq. Socialism, 228, 229 Society v. the individual, 223 et seq. Society, and morality, 306 Sociology, dependent on biology, 231 Sollier, Dr., on sensations at death, 130 Solomon, quotation from " Eccle- siastes," 233 Somnambulism, analysis of, '200 et seq. Sorbose, fermentation of, 106 Soured milk, use of, 171, 181, 182 Sparrow, fecundity of, 58 Spencer, Herbert, criticism of Kant, 310 criticism of socialism, 230 theory of morality, 316, 322, 324. 327 Spermatozoa, in old age, 35 Spermine, 139, 140 Stadelmann, on lactic acid in dia- betes, 170 Statistics on suicide, 3 Stature, in old age, 8, 9 Stein, Mde. von, 267, 268, 273 Steller's sea-cow, 213 Stern, M., on disinfection of intes- tine, 156 Stohmann, on digestion in sheep, 74 Stoics, 309 Stragesco, Dr., on digestion in mammals, 63 Strasburger, on disinfection of in- testine, 156, 157 on microbes in constipation, 70 Suicide, 3, 4, 237, 238, 265, 311 Sully-Prudhomme, definition of morality, 303 Suprarenal capsules, and atheroma, 32 Swimming, instinctive power of, 197, 198, 207 Syphilis, 31, 37, 145, 146. 302, 304 Switzerland, centenarians rare in, 91 Tanacol, as an intestinal antiseptic, 156 Taoism and immortality, 137, 138 Taste, analysis of, 243 Tavel, M., operations on large in- testine, 152 et seq. Taylor, Bayard, translation of Faust, 285 Termites, 220, 221 Testis, emulsion of, as used by Brown-S6quard, 139 resistance of, to senescence, 35 Thanatology, 131 Theophrastus, 132 Thymol, as an intestinal antiseptic, 157 Thyroid, effects of extirpation of, 32. 33. 34 Timon of Athens, quotation from, 307 Tissier, Dr., on Bacillus bifidus, 161 on use of lactic microbes, 181 Tissier, and Martelly, on putrid food, 164 Tobacco and longevity, 93 Tokarsky, on natural death, 126 Tolstoi, and death, 94 " Death of Ivan Ilyitch," 318 Tortoise, 11, 12, 13, 51 Touch, sense of, in the blind, 257 Troubat, M., on instinctive swim- ming, 198 Trees, age and death of, 96, 97, 98 Trypanosoma, 124 Unicellular organisms, death of. 95 Urine, analysis of, in a centen- arian, 7 Utilitarianism, 305 Vacherot, criticism of Kant, 313 Varenetz, 172 Vascular glands, relation to old age, 33, 34 , ^ • ■ Verworn, Max, on death in in- fusoria, 95 . , . Vinegar, in preservation of food, i6s Vivisection, 301 Voisin, M., criticism of neurono- phagy, 20 Voltaire, 92, 235 Volz, on swimming power of gib- bons, 198 Wales, IVIr., quotation from Riley, ■74 Weber, Dr., on regimen for old age, 140, 14' , , . Weichardt, on cause of fatigue, 122, 123 INDEX 343 Weinberg, Dr., on preparation of human serums, 150 on thyroid gland in aged, 33 Weiske, on digestion in sheep, 78 Weismann, A., on cause of old age, IS, 16 on death in infusoria, 95 on duration of life, 41, 43, 45, SI " Weltschmerz, " in German poetry, 236 Werther, Goethe's, 263, 267 Westergaard, statistics of mor- tality, 142, 144 Wiedersheim, on intestinal tract, 60 Wine, Goethe and, 271, 279 Wolff, J. H., Goethe's friend, 271 Women, education, 224 et seq. Yahourth, use in intestinal putre- faction, 168, 170, 175, 177, 178 Yeast, conditions of growth, 106 Zeigan, Dr., on adrenaline, 122 Zell, Dr., on blind persons, 259 Zelter, Goethe's friend, 265 Zola, " La Joie de Vivre," 248 Zoological Gardens of London, 51, 81 Zortay, Pierre, age of, 87 The most valuable production since Darwin's " Origin of Species." The Nature of Man Studies in Optimistic Philosophy By Elie Metchnikoff Sub-Director of the Pastejr Institute, Paris Translated with an Introduction by P. Chambers Mitchell Secretary of the Zodlogical Society Octavo. Illustrated ... Net, $3.oc It is not often that a scientific book may be read with ease, profit, and pleasure by the general reader, so that M. Metchnikofl's book comes in the nature of an agreeable surprise. It is marked by a refreshing naivetS and a large simplicity which are characteristically Russian. The scien- tific importance of this work is so great that it is spokpn of in England as the most valuable production since Darwin's Origin of Species. Opinions of tKe Press **An extremely interesting and typical book. . , . 'Wicli a distin- guished frankness, M. Metchnikoff defines his attitude to our universal prepossessions. It is his theory that the infirmities of age are to be overcome. If there be ground for this conception, humanity is to be profoundly changed and what we call life now, will be the childhood and youth of that longer and larger life."— H. G. Wells, in London Speaker. "Undoubtedly a great book (in some quarters it has been hailed as the greatest since Darwin's famous message to the world) and should be read by all intelligent men and woraen." —The Nation. " A book to be set side by side with Huxley's Essays, whose spirit it carries a step further on the long road towards its goal."— A/iwV ana Express. New York— Q. P. Putnam's Sons— London ■'A scientific monograph of the first order.'' Immunity in Infective Diseases By Elie Metchnikoff Sub-Director of the Pasteur Institute, Paris Author of "The Nature of Man, " etc. Translated by Francis Q. Binnie 8vo. Illustrated. Net, $5.25 " It would be impertinent to commend his know- ledge of the subject, but it is permissible to remark that he here shows himself an expounder of the first order. His marshalling of the multitudinous details is masterly and so lucid that any one who knows the meaning of the Words can follow it with ease. And these qualities are enhanced by the true scientific spirit and scrupulous fairness with which arguments are handled. The present position, as here stated, is that resistance to disease is effected both by the white cells and by various substances in the fluids, but that the latter are also produced by the cells. 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