Class Be ^oj 
 
 B()()k__lLi^_ 
 
 PUKSKNTh:i) BY 
 
 / f^2 
 
ELEiMENTS VXI^O 
 
 OF 
 
 L G I C K. 
 
 BY 
 
 JOHN ANDREWS, D. D. 
 
 LATE VICE-PROVOST 
 OF THE UNIVERSITY OF PENNSYLVANIA. 
 
 THE FIFTH EDITION. 
 
 Quicquid prsecipies, esto brevis ; ut cito dicta 
 Percipiant animi dociies, teneantque fidelts. 
 Omne supervacuum pleno de pectore manat. 
 
 PHILADELPHIA : 
 
 PRINTED AND PUBLISHED BY R. H. SMALL, 
 
 No. 165, Chesnut Street. 
 
 1835. 
 

 7;- 
 
 District of Pennsylvania j to wit : 
 
 BE IT REMEMBERED, That on the seco-.id day of December, in 
 
 ^^^^ the Ihirty-second year of the Independence of ihe U ited 
 
 L.S. States of America, A. D- 1807, Benjamin B. Hopkins, & Co. 
 
 ^^^ of the said disirict, have deposited in this Office the Title of a 
 
 Book, the right whereof the) claim as Proprietors, in (he words 
 
 following to wit : 
 
 " Elements of Logick. By John Andreiv^, I). D Vice-Provost of 
 the University of Pennsylvania. The second edition, -with corrections 
 and additio7is. 
 
 Quicgnid prcecipies. esto brevis ; ut cito dicta 
 
 Percipiaut animi dociles, teneantque fdeles . 
 
 Omne mipervacinL7n pleno de pectore manat.'^^ * 
 In conformity to the Act of the Congress of the United StSes, intituled 
 **An Actforthe encouiagement of i^ aining,by securing the copies of maps, 
 charts, and books, to the authors and proprietors of such copies^ during 
 the times therein mentioned." And also to the Act, entitled, *' An act 
 supplementary to an Act, entitled, *^ An act for the encouragement of 
 learning, by securing the copies of maps, charts, and books, to the au- 
 tho'R and proprietors of such copies during the times therein mention- 
 ed;" and extending the benefits thereof to the artsof designing, engraving, 
 and etching historical and other prints." 
 
 D. CALDWELL, 
 Clerk of the District of Pennsylvania. 
 
 q;^ The above Copy Right has been purchased by Abraham Smaix, 
 and IS regularly transferred to him. 
 
 ^^4.^0. «^//f 3a 
 
PREFACE. 
 
 OF the few treatises of Logick which 
 the author of the following compilation has 
 perused, Duncan's has always appeared to 
 him to be the best. But this treatise, how- 
 ever excellent, is for the most part too dif- 
 fusive, and in some places, perhaps, even 
 too scientific, for the use of young begin- 
 ners; at the same time that it omits a num- 
 ber of particulars, of which (as they are 
 generally taught in the schools, and occa- 
 sionally alluded to in conversation as well 
 as books) a teacher would not wish his pu- 
 pils to be wholly ignorant. To obviate 
 
these objections, and yet retain as much as 
 possible the features of Duncan, is the aim 
 of the present compend ; which was com- 
 posed some years ago, and is now printed, 
 that the classes, for whose use it was inten- 
 ded, may no longer have the trouble of 
 transcribing it. 
 
ELEMENTS 
 
 OF 
 
 L O G I C K. 
 
 liOGicK is that science which explains 
 the operations of the human understanding, 
 in acquiring and communicating knowledge. 
 And as these have been usually stated to 
 be four, — apprehending, judging, rea- 
 soning, and ARRANGING OUR THOUGHTS in 
 
 a suitable manner; so Logick, which treats 
 of these operations, is usuallj^ divided into 
 four parts. 
 
 B 
 
PART I. 
 
 Of Simple ,S.pprehension. J 
 
 Simple apprehension being that opera- 
 tion of the mind by which it is furnished 
 with ideas, a treatise on it, is, in a great mea- 
 sure, a treatise on ideas, and on the. proce- 
 dure of the mind with respect to them : and it 
 is also a treatise on words and definitions; 
 because, without these, we should often be at 
 a loss both in acquiring and communicating 
 our ideas. The first part, therefore, of Lo- 
 gick, may be divided into two chapters : one, 
 treating of ideas ; and the other, of terms and 
 definitions. 
 
4 
 
 CHAPTER 1. 
 
 Of simple Apprehension , and the faculties; 
 by lahich it is exerted. — Of Ideas, or the 
 first principles of knowledge. — Of the 
 sources from which they are derived ^ and 
 of the different sorts of them. 
 
 Simple Apprehension is that operation 
 of the understanding by which it attends to^ 
 and notices, the several objects that are pre- 
 sented to it. It is called simple apprehension; 
 because it is employed in the mere apprehend- 
 ing or noticing of things ; w ithout comparing 
 them with each other, or assigning to them 
 any attributes ; which is the province of 
 judgment. And by this operation it is, that 
 the mind, as we have already observed, is 
 
8 
 
 furnished with ideas : for without previously 
 attending to, and noticing, the objects that 
 are presented to it, it is impossible that the 
 mind should ever have any ideas of them ; 
 or, in other words, be able to re[)resent 
 to itself the appearances which they ex- 
 hibit. 
 
 In performing this operation, two facul- 
 ties are made use of, which are quite dis- 
 tinct from each other ; sensation, and con- 
 sciousness. If the object occurring be an 
 external thing, the mind perceives it, and 
 its qualities, by means of the senses ; and 
 the power of doing this is called the fa- 
 CULTY OF SENSATION : if it be an internal 
 thing, that is, if it be any operation or emo- 
 tion of the mind, the mind attends to and 
 notices it, without making use, so far as we 
 know, of any bodily organ : and it is this 
 powder, which we call the faculty of con- 
 sciousness. 
 
9 
 
 The term Idea is derived from the Greek 
 word E/cT^, I see : and by ideas are meant, the 
 views which the mind takes of things, when 
 they are no longer present. In the language 
 of the schools, ideas are the types or resem- 
 blances of things ; and things themselves are 
 the archetypes, or originals of which the re- 
 semblances are made. When an external 
 object is present, and attended to by my mind, 
 I am said to perceive it; and when my mind 
 is engaged in any operation, or agitated by 
 any passion or emotion, I am said to be con- 
 scious of that operation, or of that passion 
 or emotion: but when the external object is 
 no longer present, so as to affect the organs 
 of sense, or when the operation which had 
 engaged my mind ha« ceased to engage it, or 
 the passion or emotion, by which 1 was a«*i. 
 tated, now agitates me no more, I am capable 
 of thinking of the object which I before per- 
 ceived, or of the operation or emotion of which 
 B3 
 
10 
 
 J was conscious, and of representing to my- 
 self the appearances which they respectively 
 exhibited ; and when I do so, I am said to 
 have IDEAS of them. 
 
 It has been stated^ that all external 
 things and their qualities are noticed by 
 means of the senses: and internal things, 
 that is, the operations and emotions of the 
 mind, by consciousness : now all the objects 
 of which we have any knowledge, are either 
 external things and their qualities, or the 
 operations and emotions of the mind : and, 
 consequently, all our ideas, how numerous 
 soever they may be, are derived from these 
 two sources. 
 
 As ideas are the first elements of all our 
 knowledge ; so sensation and consciousness 
 are the first of our intellectual faculties 
 which are exerted by us. And as we can 
 have no ideas of the operations of our 
 
11 
 
 minds until these operations are exerted ; 
 and as they cannot be exerted, before the 
 Uiind is furnished with ideas of external 
 things about which to employ them ; the 
 ideas which give the first employment to 
 our faculties, are evidently the ideas of ex- 
 ternal things, communicated by the stnses : 
 whence it is plain, that all our linowledge 
 must begin in sensation ; and that the opera- 
 tion of this faculty is prior even to that of 
 consciousness. 
 
 Ideas are either simple or complex. 
 A simple idea is an idea of a simple object ; 
 that is, an object without parts ; or it may 
 be defined, an idea which cannot be resolv- 
 ed into two or more ideas. A complex idea 
 is an idea of a complex object; that is, of 
 an object that consists of parts : or, it is aa 
 idea, that may be resolved into two or more 
 ideas. 
 
13 
 
 To the former of these classes belong 
 all our ideas of qualities, and of the opera- 
 tions and emotions of our own minds. The 
 qualities of external things are called sensl 
 BLE QUALITIES ; and may be reduced to five 
 general heads, according to the several 
 senses which are affected by them. Light 
 and colours are perceived by the eye : 
 sounds, by the ear : tastes, by the tongue ; 
 smells, by the nose; and heat and cold, 
 roughness and smoothness, hardness and 
 softness, &c. by the touch. Extension, 
 figure, rest, and motion, we perceive by two 
 senses ; seeing, and feeling. To which 
 may be added, that our ideas of pleasure 
 and pain, of power, existence, unity, and 
 succession, are conveyed into our under- 
 standings both by sensation and conscious- 
 ness ; that is, both by the action of objects 
 around us, and the consciousness of what we 
 feel within. Other qualities are l^TKLLEC. 
 
 TUAL, MORAL, &C. 
 
13 
 
 To this general view of our simple 
 ideas may be sulyoined the two following 
 observations. The first is, that simple 
 ideas can only he conveyed into the mind 
 by the proper channels and avenues pro- 
 vided by nature ; insomuch that if we are 
 destitute of any of those inlets^ all the ideas, 
 thence arising, are absolutely lost to us; nor 
 can we, by any quickness of understanding, 
 find a remedy for this want. A man born 
 blind is incapable of ideas of light and co- 
 lours ; as one, w ho is born deaf, can form 
 no conception of sounds. And hence it 
 appears, that these our simple ideas are just 
 such as nature furnishes them, and have no 
 dependence on our will : we can neither 
 destroy them when in the understanding: 
 nor fashion or invent any new one, not 
 taken in by the ordinary means of appre- 
 hension. So that the utmost bounds of hu- 
 man knowledge cannot exceed the limits of 
 our simple ideas and their various combina^ 
 
11 
 
 tions. The second is, that though the mind, 
 in multiplying its conceptions, can avail it- 
 seir of no other materials than those which 
 are furnished by sensation and conscious- 
 ness : yet. as it has a power of combining 
 these materials in a great variety of ways, 
 it finds itself in possession of an inexhaus- 
 tible treasure of ideas, sufficient to employ 
 it to the full extent of its powers. 
 
 Complex ideas arc of two sorts : those 
 
 WHICH ARE CONVEYED INTO THE MIND BY 
 THINGS REALLY EXISTING IN NATURE ; AND 
 THOSE WHICH ARE THE WORKMANSHIP OF 
 THE MIND ITSELF. 
 
 Things really existing in nature are all 
 comprised under the general name of sub- 
 stances ; w hich are either material or im- 
 material. And the usual definition of a sul>- 
 stance is, that it is a thing which subsists of 
 itself^ without dependence upon any created 
 
15 
 
 beings and is the subject of modes. ^ The 
 idea, for example, of a material substance 
 includes in it the idea of a thing subsisting 
 of itself; and the ideas of its qualities, by 
 which only, as we find by experience, it is 
 made known to us: the idea of an immate- 
 rial substance, in like manner, includes the 
 idea of a thing subsisting of itself; and the 
 ideas of its operations^ by which only, as 
 we also find by experience, it is made known 
 to ns. And hence it appears that it is nqt 
 without reason, that all our ideas of sub- 
 stances are considered as complex ideas. 
 
 Modes are divided into essential and 
 ACCIDENTAL. An essential mode is that 
 which cannot be separated from its subject^ 
 without destroying the nature of the sub- 
 ject : an accidental mode is that which mav 
 
 That is, of qualities or attributes* 
 
16 
 
 be separated from its subject, and the nature 
 of its subject remain the same as it was be- 
 fore. Roundness, for example, is an essen- 
 tial mode of a ball ; because a thing cannot 
 be a ball without being round ; but any par- 
 ticular colour is an accidental mode of a 
 ball; because if a ball, which is now blue, ' 
 were to be painted white, it would still be a 
 ball as much as ever. 
 
 Essential modes are divided into pri- 
 mary aind SECONDARY. A primary essen- 
 tial mode is that which is derived from no 
 other mode, and constitutes a thing what it 
 is. A secondary essential mode is that, 
 which, although inseparable from its sub- 
 ject, is derived from some other mode. 
 Thus roundness is a primary essential 
 mode of a ball ; because we do not conceive 
 of it as derived from any other quality of a 
 ball ; but volubility, or aptness to roll, 73 a 
 secondary essential mode of a ball-; because 
 
17 
 
 it arises from another quality of it, that is, 
 its roundness. The primary essential mode 
 has been called differentia, or the differ^ 
 ence; the secondary essential mode, pro- 
 FRiuM, or a property 5 and the accidental 
 mode^ ACCiDENS. 
 
 Complex ideas, which are the workman- 
 ship of the mind, are divided into com- 
 
 POUND — UNIVERSAL, GENERAL, or ABSTRACT 
 — and RELATIVE. 
 
 Compound ideas are those, which the 
 mind forms by putting two or more ideas to- 
 gether. These combinations are sometimes 
 made by adding the same idea to itself : 
 thus, by adding the idea of unity to itself re- 
 peatedly, and retaining the several amountis 
 in our minds, we come by all the different 
 combinations of numbers : in the same way 
 are formed the different ideas of yards, 
 perches, furlongs, miles, leagues, &c ; also 
 
 C 
 
18 
 
 those of weeks, months, years, &c. But, 
 more frequently, our compound ideas are 
 formed by combining ideas of a different 
 kind together. The composer of music, 
 for example, forms the idea of a tune which 
 he is composing, and the mechanic, the 
 idea of a machine which he is projecting, — 
 by bringing together, in the former case, a 
 number of notes — and, in the latter, of parts 
 that are diflferent from each other. 
 
 An abstract, universal, or, as it is more 
 commonly called, a general idea, is an idea 
 that will apply to several individuals, or to 
 several classes of individuals. If it apply 
 to individuals only, the class which corres- 
 ponds to it, and comprehends individuals, 
 is termed a species; if to several classes 
 of individuals, the class which corresponds 
 to it, and comprehends these several 
 classes of individuals, is termed a genus. 
 The formation of these ideas depends on a 
 
19 
 
 power which the mind possesses of remov- 
 ing, from its idea of any object, what is pe- 
 culiar to that object ; from its idea of an 
 individual, whatever is peculiar to that iu- 
 dividual ; and from its idea of a species, 
 whatever is peculiar to that species : a pow- 
 er, which^ by the writers on the human 
 mind, is called the faculty of abstrac- 
 tion. And hence it appears, that it is not 
 without reason, that our general ideas are 
 ranked among those which are the work- 
 manship of the mind, and have nothing in 
 nature to which they correspond. 
 
 But that this may be better understood, 
 it will be worth while to take a more dis- 
 tinct view of the process of the understand- 
 ing in tlie formation of these ideas. All the 
 things in nature are individual things : that 
 is, every thing is itself, and one ; and not 
 another, and more that one. But when we 
 come to take a view of the several indivi- 
 
20 
 
 duals^ and observe that a number of them 
 resemble each other in one or more particu- 
 lars of importance, selecting the particulars 
 in which they agree, and removing all those 
 in which they disagree, we frame to our- 
 selves a general idea applicable to several 
 individuals ; that is, to a particular species. 
 Thus certain animals being found to resem- 
 ble each other in having an erect form, and 
 in being endowed with the faculties of rea- 
 son and speech, we take these important 
 particulars which are common to them all, 
 and excluding what is peculiar to each, we 
 form a general idea, to which we give the 
 name of man ; and this name belongs equal- 
 ly to every individual who is possessed of 
 the form and faculties above mentioned. 
 This is the first step or gradation in the 
 forming of abstract ideas, when the mind 
 confines itself to the consideration of indi- 
 viduals, and frames an idea that compre- 
 liends such only under it. 
 
31 
 
 Again : having ranged things into spe- 
 cies, according to the resemblance found 
 among them, we begin to compare the se- 
 veral species with each other; and often 
 observe^ in these also, a resemblance^, in one 
 or more particulars of importance. Upon 
 this, throwing out all the particulars in 
 which they disagree, and retaining those 
 only, in which there is a resemblance, we 
 frame a still more general idea, compre- 
 hending under it several species. Thus^ 
 a sparrow, a hawk, an eagle, &c. are dis- 
 tinct species of birds : they nevertheless re- 
 semble each other in being cov^ered with 
 feathers, and provided with wings which 
 bear them through the air: out of these 
 particulars we form a new idea, and appro- 
 priating to it the name bird^ mark by that 
 word a higher class, which comprehends in 
 it all the former This higher class, which 
 extends to several species of things, is 
 called a genus; and is the second step 
 
which the mind takes in the formation of its 
 general ideas. 
 
 But, in rising from particulars to gene- 
 rals, the mind does nt)t confine itself to one 
 or two gradations. For when we have re- 
 duced things into species, and these again 
 into genera, these genera are often found to 
 resemble each other in some particulars, 
 which being combined together into one 
 idea, includes a new and more comprehen- 
 sive cUss of things. Thus bird is a genus, 
 comprehending the several species of spar- 
 row, hawk, eagle, &c. : fish is a genus, in- 
 cluding the several species of living crea- 
 tures which inhabit the waters, as dolphins, 
 sturgeons, &c. : beast or quadruped, and in- 
 sect, are also genera, which extend to many 
 species: yet all these diflFerent genera have 
 this in common, that they are provided with 
 organical bodies filled for the purposes of 
 life and spontaneous motion. An idea, 
 
33 
 
 therefore made up of these particulars only, 
 will comprehend all the genera above men- 
 tioned ; and the word, animal, by which it 
 is expressed, denotes a higher genus, in- 
 cluding the several creatures endued with 
 life, sense, and spontaneous motion. 
 
 Further : all things, animate and inani- 
 mate, resemble each other in this respect, 
 that they are created ; whence we refer 
 them to a genus still higher, which may be 
 called creature: a name, which belongs 
 equally to every genus and species of cre- 
 ated things, and to each individual thing 
 that is created. 
 
 And further still : all things, whatever, 
 exist, or are ; and in this respect are said to 
 resemble each other; in which view we 
 refer them to a genus still higher, called 
 Beings which is the highest possible genus. 
 
2i 
 
 In a series of genera, rising in this 
 manner one above another^, each successive 
 genus is called-in the schools, a genus 
 
 GENRRALtUS, Or HIGHER GENUS J aud the 
 
 genus by which each series is terminated, 
 they distinguish by the name of genus 
 GENERALissiMUM. lu like manner, the se- 
 veral genera, comprehended under a higher 
 genus, are, in re^spect to it, considered as 
 species ; and as these have also species 
 under them, the inferior divisions, are, for 
 the sake of distinction termed species 
 SPECIALIORES, or LOWER SPECIES, And the 
 
 lowest subdivisions of all, comprehending 
 It 
 
 only individuals, (which, as has been al- 
 ready mentioned, constitute the proper s|)e- 
 cies) are, in respect to the series, denomi- 
 nated the SPECIES SPECIALISSIM^. All that 
 
 lie between these and the hi2;hest distribution 
 of things, or genus generalissimura, are the 
 
 INTERMEDIATE GENERA AND SPECIES ; which 
 
25 
 
 are termed successively genus generalius, 
 or species specialior, according as we con- 
 sider them in the ascending, or descending 
 series of our ideas; or, to speak in the 
 language of logicians, according to their 
 ascent, or descent, in the linea prcedica- 
 mentali. 
 
 And here we may take occasion to men- 
 tioQ merely, that, by the ancient writers of 
 logick, a genus generalissiraum, with all its 
 divisions and subdivisions, was termed a 
 CATEGORY, or PREDICAMENT. Abd as Aris- 
 totle fancied, that all things in nature might 
 be reduced to ten general heads, or classes, 
 namely, substance, quantity, quality, rela- 
 tion, action, passion, place, time, situation, 
 and clothing; these have been called the 
 
 TEN CATEGORIES. 
 
 It is of more importance to remark, 
 that, though many of our general ideas are 
 
^6 
 
 evidently combinations of different simple 
 ideas, and in that view of them are included 
 in the class of compound ideas, we are 
 carefully to distinguish between an idea as 
 it is compound^ and as it is general or uni- 
 versal. 
 
 An idea is termed compound, with re- 
 spect to the several ideas which are com- 
 bined in it ; general or universal, with re- 
 spect to the individuals, species, or genera, 
 to which it extends. Thus, the idea of a 
 bird, considered as a compound idea, in- 
 eludes life, sense, spontaneous motion, a cov- 
 ering of wings, feathers, &c. : but, as a ge- 
 nevaX idea, it denotes the several species of 
 the feathered creation, the hawk, the eagle, 
 the lark, &c. ; to all which it extends with 
 equal propriety. In the former case, the 
 several parts of the compound idea are 
 called its compkehension ; in the latter, 
 the genera, the species, and the individuals. 
 
37 
 
 to which the universal idea may be applied 
 are called its extension. 
 
 The third and last division, of those 
 complex ideas which are the workmanship 
 of the mind, consists of our relative ideas. 
 A relative idea, is an idea which arises 
 from the comparing of things, one with an- 
 other, and observing (heir corre*>pondencies. 
 For the mind is not limited to the consi- 
 deration of objects, as they are in them- 
 selves merely: but can examine them as 
 connected with other things brought into 
 view at the same time. And when it does 
 so, and thence acquires new ideas, the ideas 
 thus acquired are called relative ideas; 
 and make, as is supposed, the largest class 
 of our ideas. For every single object will 
 admit of almost innumerable comparisons 
 WHh others, and, in this way, may become 
 a very pleoiiful source of ideas to the un- 
 ^lerstanding. Thus, if we compare one 
 
28 
 
 thing with auother in respect to bulk, we 
 get the idea of greater and less, or of equa- 
 lity : if, in respect of time, of older and 
 younger : ViwA so of other relations, which 
 we can pursue at pleasure, and almost with- 
 out end. 
 
 So much, with respect to ideas ; which 
 are the subject of the first chapter. We 
 have stated, that all our simple ideas are 
 conveyed into the understanding either by 
 sensation or consciousness ; and are the ma- 
 terials out of which all others are formed : 
 that the mind, though it has no power over 
 these, either to fashion or to destroy tliem, 
 can yet combine them in an infinite number 
 of ways ; and that from their various com- 
 binations result all our complex ideas : that 
 these complex ideas are of two principal 
 kinds; first, such as are derived from with- 
 out, and represent those combinations of 
 simple ideas that have a real existence in 
 
29 
 
 nature, — of which sort are all our ideas of 
 substances ; secondly, such as are formed 
 by the mind itself, arbitrarily uniting and 
 putting together its ideas : and that, as these 
 last make by far the largest class, and com- 
 prehend all those ideas which may be pro- 
 perly termed our own, as being the work- 
 manship of the understanding : so they fall 
 very naturally under three distinct heads* 
 For either the mind combines several sim- 
 pie ideas together in order to form them 
 into one complex idea, in which the number 
 and quality of the ideas united are princi- 
 pally considered; in which way we become 
 possessed of all our compound ideas : or it 
 fixes upon any one of its ideas, whether it 
 be a simple or compound idea, or an idea of 
 a substance, and leaving out the circum- 
 stances of time, place, real existence, and 
 whatever reiiders it particular, considers 
 what it has in common with other*?, and of 
 that makes an idea which will apply to all 
 
 D 
 
30 
 
 of a kind ; whence our abstract or universal 
 ideas are derived : or, lastly, it compares 
 things one with another, examines their mu- 
 tual connexions^ and thereby furnishes it- 
 self with a new set of ideas, known by the 
 name of relative ideas; which, as has been 
 already remarked, make by no means the 
 least important class of our ideas. 
 
.Jl 
 
 CHAPTER II. 
 
 Of Terms and Definitions. 
 
 Having seen, in the preceding chapter, 
 how our ideas are acquired ; let us now 
 proceed to examine how they are communi- 
 cated. Ideas themselves are not visible, 
 nor can they be perceived by any outward 
 sense. But God, designing us for society, 
 and to have fellowship with those of our 
 kind, has pro\ided us with organs fitted to 
 frame articulate sounds, and given us also 
 a capacity of using those sounds, or terms, 
 as signs of ideas. Hence our ideas, which 
 otherwise must have been locked up, as it 
 were, in our own breasts, are brought forth 
 and made to appear. For, any number of 
 
33 
 
 meiHiaving agreed to make use of the same 
 sounds as signs of the same ideas, it is 
 evident^ that the repetition of these sounds 
 must excite the same ideas in them all. 
 When, for instance^ any train of ideas 
 takes possession of my mind^ if the terms^ 
 or sounds, by which I am wont to express 
 them, have been annexed, by those with 
 whom I converse, to the very same set of 
 ideas^ nothing is more evident, than that by 
 repeating those terras, according to the te- 
 nour of my ideas, I shall raise in their 
 minds the same train that has taken posses- 
 sion of my own. Hence, by barely attend- 
 ing to what passes within themselves, they 
 will also become acquainted with the ideas 
 in my understanding, and have them in a 
 manner exposed to their viev/. 
 
 So that we here clearly perceive how a 
 man may communicate his sentiments to an- 
 other, provided the language, in which he 
 
33 
 
 converses, be copious enough to contain 
 words, appropriated to all his ideas ; and 
 provided the person to whom he speaks, is 
 possessed of the same ideas which he ex- 
 presses, and has been accustomed to con- 
 nect them with the same terms. 
 
 But as this is not always the case, and 
 as we may often have occasion to communis 
 cate to others a new idea, that is, an idea 
 that has never yet entered their minds, and 
 which consequently they cannot as yet have 
 connected with any term ; it may be asked^ 
 by what means it is possible that the com* 
 munication of such an idea should be of* 
 fee ted ? 
 
 This appears to be a difficulty : and, to 
 solve it, it will be necessary to observe, 
 fir^t, that no worri can be to any man the 
 si2;n of an dea, till that idea comes to have 
 a real existence in his mind. For vvoids 
 
31 
 
 being only so far intelligible, as they denote 
 known ideas ; where they have none such 
 to answer to them, there they are plainly 
 sounds without signification, and of course 
 convey no information. But no sooner are 
 the ideas, to which they belong, produced 
 in the understanding, than, finding it easy 
 to connect them with the established words, 
 we can join in any agreement of this kind 
 made by others, and enjoy the benefit of 
 their discoveries. The first thing, there- 
 fore, to be considered, is^ how these ideas 
 may be conveyed into the mind, that, they 
 being there, we may learn to connect them 
 ivith the appropriated sounds, and so be- 
 come capable of understanding others when 
 they make use of these sounds in laying 
 open and communicating their thoughts. — 
 Now, to comprehend distinctly how this 
 may be done, it will be necessary to call to 
 mind the before mentioned divisions of oup 
 ideas into simple aad complex. And first; 
 
35 
 
 as to our simple ideas, it has been already 
 obseived, that they can find no admission 
 into the niitul, but by the origiual fountains 
 of knowledge, sensation, and consciousness. 
 If therefore any of these ha- e as yet no 
 being in the understanding, it will be im- 
 possible by wonis to excite them there. A 
 man, who had never felt the impression of 
 heat, conld not be brought to comprehend 
 that sensation, by any thing which we could 
 say to explain it. If we would produce the 
 idea in him, it mu«t be by applying the pro- 
 per object to his senses, and bringing him 
 within the influence of a hot body. When 
 this is done, and experience has taught him 
 the sensation, to which men have annexed 
 the name keat^ this term may then become 
 to him the sign of that idea; and he is 
 thenceforth capable of understanding the 
 meaning of the term ; which, before, all the 
 words in tlie world would not have been 
 sufiBcieut to convey into his mind. Tlie 
 
36 
 
 case is the same with respect to light and 
 colours : a man born blind, and by this mis- 
 fortune destitute of the only conveyance for 
 the ideas of these objects, can never be 
 brought to understand the terms by which 
 they are expressed. The reason is plain : 
 they stand for ideas which have no exist- 
 ence in bis mind ; and as the organ, appro- 
 priated to tlieir reception, i^ wanting, all 
 other contrivances are vain, nor can these 
 ideas, by any force of description, be excited 
 in him. But, with our complex id<»as, it is 
 quite otherwise. For, these being no other 
 than certain combinations of simjile ideas 
 put together in various forms, if the simple 
 ideas, out of which the complex ideas are 
 B)ade, have already got admission into the 
 understanding, and the terms serving to ex- 
 press them be known, it will be easy, by 
 enumerating the several ideas included in 
 the combination, and marking tlie order 
 and manner in which they are united; to 
 
37 
 
 raise any complex idea in the mind. Thus 
 the idea answering to the terra, rainbow, 
 may be readily excited in the imagination 
 of another, who has never seen the appear- 
 ance itself, by describing the figure, size, 
 position, and order of colours ; if we sup- 
 pose these several simple ideas, with their 
 names, sufficiently known to him. 
 
 The answer, then, to the question pro- 
 
 posed above, is now sufficiently obvious 
 
 If the new idea, which we wish to comma- 
 nicate toothers, be a simple idea, there is 
 no other way than to refer them to those 
 objects in nature whence the idea is to be 
 obtained : but, if it be a complex idea, its 
 meaning may be explained by enumerating 
 the ideas included in it; that is, by defin- 
 iiig it. 
 
 And here we see the nature and use of 
 DEFINITIONS. They are used to unfold a 
 
38 
 
 complex idea ; and two things are required 
 in them : first, that all the simple ideas, out 
 of which the complex one is formed, be dis- 
 tinctly enumerated ; and secondly, that the 
 order and manner of combining them be 
 clearly explained. Where a definition has 
 these requisites, nothing is wanting to its 
 perfection; because every one who reads it, 
 and understands the terms, seeing at once 
 what ideas he is to join together, and also 
 in what mannner, he can, at pleasure, form, 
 in his own mind, the complex idea answer- 
 ing to the term defined. 
 
 But this rule, though it extends to all 
 possible rases, and is indeed that alone to 
 which we can have recourse where any 
 dou! t or difficulty arises, it is not, however, 
 necessary, or even expedient, to practise in 
 every particular instance. Many of our 
 ideas are extremely complex ; and, of 
 course^ to enumerate all the simple ideas, 
 
39 
 
 out of which they are formed, would he a 
 very trouhlesome and tedious work. For 
 which reason, loejicians have e.stahlished a 
 certain compendious mode of defining; of 
 which, it may not be amiss to give here a 
 short account. If the thing to be defined 
 be a species, they give the nearest genus 
 aird the specific difference; or, in other 
 words, they refer it to its nearest genus, 
 and then add those circumstances that make 
 the species^ which they are defining, to dif- 
 fer from every other species belonging to 
 that genus. For, as the idea of a genus is 
 formed by dropping what is peculiar to tarh 
 of the several species referred to it, and 
 retaining those particulars which they all 
 possess in common; so, on the other hand, 
 by adding to the genus what is peculiar to 
 any one of the species included in it, we 
 form Hu adequate idea, and give a complete 
 definition, of that species. In like manner, 
 if the thing to be defined be an individual^ 
 
10 
 
 the logical definition will consist of the 
 SPECIES and the numerical difference ; 
 or, in other words, of the species, and 
 those particukrs that distinguish the indi- 
 vidual which we are defining, from every 
 other individual belonging to that species. 
 For, as the idea of a species is formed by 
 dropping what is peculiar to the several 
 individuals referred to it, and retaining 
 those particulars only which they possess 
 in commun; so, by adding to the species 
 ■what is peculiar to any one of the indivi- 
 duals included in it, we form an adequate 
 idea, and give a complete definition, of that 
 individual. 
 
 We shall conclude with observing, that 
 definitions have been distinguished into two 
 kinds; the definition of thk name, and 
 the definition of the thing. When the 
 term to be defined, refers t.) the i«lea of the 
 writer or speaker, aud the defiuiiion is dc- 
 
u 
 
 signed to show what idea he connects with 
 a certain term, it is a definition of the name. 
 And such definitions are said to be arbitra- 
 ry ; because, as words are not natural, but 
 merely artificial, signs of ideas, every man 
 is at liberty to annex to a term what idea 
 he pleases. But where the reader, or hear- 
 er, is supposed to know that a certain term 
 is connected with a particular idea, and 
 where the design of the definition is to un- 
 fold that idea, that the nature of the thing 
 of which it is the type or resemblance, may 
 be fully understood, it is a definition of the 
 thing. And such a definition is not arbi- 
 trary : because the idea of any thing should 
 be conformable to that thing; and the de- 
 finition conformable to the idea. 
 
 E 
 
*2 
 
 PART II, 
 
 Of Judgment. 
 
 All our knowledge may be reduced to 
 two heads: our ideas of things, and the 
 judgments which we form with respect to 
 them. Of our ideas, and of terms and de- ^ 
 finitions by which they are communicated, 
 we have already treated. We come now 
 to speak of our judgments ; and of propo- 
 siTiONS, by which they are communicated. 
 And here it will be proper to consider, 
 first, the several grounds of human judg- 
 ment ; and, secondly, the different sorts of 
 propositions* 
 
43 
 
 CHAPTER L 
 
 Of the GROUNDS of Human Judgment ^ oVf 
 in other words^ of the different sorts 
 
 OF EVIDENCE. 
 
 Judgment is that operation of the mind 
 by which we compare two or more ideas 
 together, with a view to determine whether 
 they agree or disagree. But although^ in 
 every act of judgment^ it is necessary to 
 bring two or more ideas together^ and place 
 them, as it were, over against each other; 
 yet, the mere comparing of two ideas toge- 
 ther is not the evidence of their agreement 
 or disagreement. What then, it may be 
 asked, is this evidence ? Or rather, (as one 
 sort of truth is supported by one sort of evi- 
 
44 
 
 dence, and another by another), What are 
 the different sorts of evidence ? 
 
 To assist us in judging of this subject, 
 it will be necessary to observe, that all the 
 objects of the human understanding are, 
 cither abstract notions of quantify and num- 
 ber^ or things really existing. Of the re- 
 lations of these abstract notions, all our 
 knowledge is certain ; being founded on 
 mathematical evidence. Of things really 
 existing, we judge, either from our own ex- 
 perience, or from the experience of other 
 men. Judging of real existence from our 
 own experience, we attain either certainty 
 or probability. Our knowledge of real things 
 is certain, when supported by the evidence 
 of external sense, consciousness, and memo- 
 ry ; and when from effects we infer causes. 
 Our knowledge of real things is probable, 
 when from facts whereof we have had ex- 
 perience, we infer facts of the same, or a 
 
43 
 
 similar kind, not experienced. Judging of 
 real existence from the experience of other 
 men, we have the evidence of their testimo- 
 ny. And thus it appears, that all sorts of 
 evidence, productive of real knowledge, may 
 be reduced to seven. — 1- Mathematical evi^ 
 dence. 3. The evidence of external sense. 
 3. The evidence of consciousness. 4. The 
 evidence of memory. 5. That evidence 
 which we have, when from effects we infer 
 causes^ 6. I'he evidence of testimony. 7» 
 Probable evidence. 
 
 Of MATHEMATICAL EVIDENCE there are 
 two sorts : intuitive and demonstrative^-^ 
 Mathematical evidence is intuitive, when^ 
 from the very nature of the ideas compar* 
 ed, it appears, at first view, that they must 
 necessarily agree or disagree. MathematU 
 cal demonstrative evidence is direct or in- 
 direct. When a conclusion is inferred fromi 
 principles which render it necessarily true^ 
 E3 
 
46 
 
 the demonstration is direct. When, by sup- 
 posing a given proposition false, we are ne- 
 cessarily led into an absurdity, it is called 
 indirect, apagogical, or ducens in absur- 
 dum. Now that must be true, which we 
 cannot, without absurdity, suppose to be 
 false. And therefore both sorts of demon- 
 stration are equally good, because equally 
 productive of absolute certainty. 
 
 All mathematical proof is founded upon 
 axioms, or self-evident propositions, the con- 
 traries of which are inconceivable. And 
 this sort of proof seems to be peculiar to the 
 sciences that treat of quantity and number ; 
 and therefore, in no other science is the ma- 
 thematical method of proof to be expected. 
 For, in the other sciences, in most of them 
 at least, truth and its contrary are equally 
 conceivable. That Julius C«sar died a na- 
 taral death is as easy to be conceived, as 
 4hat he was murdered in the senate- house. 
 
47 
 
 I feel a hard body, I do not feel a hard 
 body, I see a white colour, I do not see a 
 white colour, are all equally conceivable; 
 and yet may be either true or false accord- 
 ing to circumstances. We may conceive 
 that the sun, after setting to-night^ will ne- 
 ver appear again, or that any particular 
 man will never die : and, yet we consider 
 death as what must inevitably happen to 
 every man, and the rising of the sun to- 
 morrow as so certain, that no rational being 
 can doubt of it Though, therefore, the ma- 
 thematical method of proof is to be found 
 in the mathematical sciences only, yet satis- 
 factory proof may be found in any other 
 science : and is actually found, in every 
 part of knowledge that deserves the name 
 of science. 
 
 The EVIDENCE OF EXTERNAL SENSE, DO 
 
 less than mathematical evidence, produces 
 absolute certainty j though in another way. 
 
48 
 
 Our perception of external things is attend- 
 ed with an ^irresistible belief, that they ex- 
 ist, and are what they appear to be. When 
 I see a man or a horse, I can no more doubt 
 of his existence, than of my own ; and my 
 own 1 believe with as full assurance as that 
 two and two are four. The existence of 
 body is a self-evident fact. It needs no 
 proof; for to disbelieve or doubt of it, is 
 impossible : and it admits of none ; because 
 we know of nothing more evident to prove 
 it by. ^' ' 
 
 The EVIDENCE OF INETRNAL SENSE, Or 
 
 CONSCIOUSNESS, docs also produce absolute 
 certainty. That we have within us a think- 
 ing and active principle, called a soul or 
 mind ; which is the same thing to-day as it 
 was yesterday; is conscious of its own 
 thoughts ; and exercises a a at iety of facul- 
 ties diflferent in their objects and manner 
 of operation ; are all of them suggestions of 
 
49 
 
 internal sense or consciousness, which we 
 believe because we feel them to be true ; 
 and which if we were not to believe, would 
 bring on us the charge of irrationality. 
 
 The EVIDENCE OF MEMORY docs also 
 produce absolute certainty. A child be- 
 lieves, without any doubt, that, what he re- 
 members distinctly to have seen or heard, 
 he really did see or hear. And he believes 
 this, not because he has been told that he 
 may safely trust his memory ; but because 
 the law of his nature determines him, of his 
 own accord, to believe his memory as well 
 as his senses. Indeed if we were to dis- 
 trust our memory, or treat it as a fallacious 
 faculty, our senses would be of little use to 
 us, and we should be incapable both of 
 knowledge and experience, and also of rea- 
 soning; for we cannot be satisfied with a 
 proof, unless we remember the steps of it, 
 and believe that on that remembrance we 
 
90 
 
 may depeticK Thoughts remembered may 
 decay through length of time, and at last 
 vanish ; but, of an event or object, that part 
 which we distinctly remember, we believe 
 to have been real. We may forget the 
 whole subject of a book, and yet remember 
 and consequently believe, that we read it. 
 We may forget the proofs of a proposition, 
 and yet remember that it was formerly pro- 
 ved to our satisfaction, and acquiesce in it 
 accordingly. If in conceiving any event or 
 object, we are uncertain whether we remem- 
 ber or only imagine, belief is suspended and 
 we remain in doubt ; but no sooner are we 
 conscious that we remember, than belief 
 instantly takes place ; and we say, I am 
 certain it was so, for now I remember it 
 distinctly. 
 
 As to THE EVIDENCE THAT WE HAVE 
 W^HEN FROM EFFECTS WE INFER CAUSES, 
 
 we may observe, that the law of our nature 
 
51 
 
 determines us to believe, that whatever he* 
 gins to existj proceeds from some cause. 
 If, on going home, I should find, on the 
 table, a book, which I never saw before, 
 it would occur to me as absolutely certain, 
 that some cause had brought and some per- 
 son m^de it. For if I were to be told, that 
 nobody brought it, and that it never was 
 made, I should, without hesitation, declare 
 such a thing to be not only absurd but im- 
 possible ; and there is not one rational be=^ 
 ing who in this would refuse to concur with 
 me. Even children think in this manner, 
 and some are very inquisitive into the causes 
 of things : a proof that it is not experience 
 merely which leads us to infer the cause 
 from the effect. If the book, which I sup» 
 posed myself to find, contained wise obser- 
 vations, and was well printed and bound, 
 I mu t of necessity believe, that the author, 
 printer, and binder, were possessed of wis^ 
 dom and skill equal to the eiBFect produced. 
 
That being whom we believe to have pro- 
 ceeded from no cause but the necessity of his 
 own nature^ and to be self-existent, and 
 on all other beings independent, we must 
 also believe to have existed from eternity^ 
 or, in other words, to have had no begin- 
 ning. For if every thing that had a begin- 
 ning, proceeded from some cause, that which 
 proceeded from no cause, could have had no 
 beginning. 
 
 Probable evidence is of two sorts. — 
 One is, when, from facts whereof we have 
 had experience, we infer facts of the same 
 kind not experienced. It is natural for us 
 to think, that the course of things whereof 
 we have had experience, and now have, 
 will continue, unless we have positive rea- 
 son to believe that it will be altered. This 
 is the ground of many of those opinions 
 whicli we account quite certain. That to- 
 morrow the sun will rise, and the sea ebb 
 
53 
 
 and flow ; tliat night will follow day, and 
 spring succeed the winter ; and that all men 
 will die ; are opinions amounting to certain- 
 ty: and yet we cannot account for them 
 otherwise than by saying, that such has been 
 the course of nature hitherto, and we have 
 no reason to believe that it will be altered. 
 When judgments of this kind admit no 
 doubt, as in the example given above, our 
 conviction is called moral certainty. I 
 am morally certain, that the sun will rise to» 
 morrow, and set to- day, and that all men 
 will die, &c. The instances of past experi- 
 ence, on which these judgments are founded, 
 are innumerable; and there is no mixture of 
 contradictory instances which might lead us 
 to expect a contrary event. But if the ex- 
 periences, on which we ground our opinions 
 of this sort, are but few in number, or mix- 
 ed with contradictory experiences, in this 
 case we do not consider the future event as 
 morally certain; but only more or less pro« 
 
 F 
 
54 
 
 bable according to the greater or less sur- 
 plus of favourable instances. The other 
 sort of probable evidence, which is termed 
 ANALOGICAL, is, when from facts whereof 
 We have had experience, we infer facts of a 
 similar kind not experienced ; or, in other 
 words, when we expect similar events in 
 similar circumstances. For example, we 
 think it probable that the planets are inha- 
 bited, they being in all respects so like our 
 earth. The force of an argument from ana- 
 logy is in proportion to the degree of like- 
 ness, that there is between the case from 
 which we argue, and the case to which we 
 argue. In the example given, the case 
 from which we argue, is the circumstance 
 of this earth's being a planet, warmed and 
 enlightened by the sun, and inhabited by 
 many varieties of living creatures ; and the 
 case to which we argue, is that of the other 
 planets, which being in all other respects 
 so similar to our earth, we think it highly 
 
probable that they must resemble it in this^ 
 in being the habitation of percipient beings. 
 A man who thinks, as Epicurus did, that 
 they aro no bigger than they appear to his 
 eye, can have no notion of their being inha- 
 bited, because to him they must appear in 
 every respect so unlike our earth. And if 
 we were to argue with him, in order to bring 
 him over to our opinion, we should begim 
 by explaining to him those particulars^ 
 wherein the earth and the other planets re- 
 semble each other. As soon as he under- 
 stands these par4;iculars as well as we, he 
 will, of his own accord, admit the probabili^ 
 ty of our opinion. 
 
 Another and the last species of evidence^ 
 upon which we are to remark in this place, 
 is TESTIMONY. It is natural for a man to 
 speak as he thinks ; and it is easy, like 
 walking forward. One may walk back- 
 ward, or sideways ; but it is uneasy, and a 
 
56 
 
 sort of force upon nature : and the same 
 thing is true of speaking one thing and ' 
 thinking another. It is also natural for us 
 to believe what others seriously tell us. 
 We trust the word of a man of whose vera- 
 city w^e have had experience ; but we also 
 credit testimony previously to such experi- 
 ence ; for children, who have the least expe- 
 rience^ are the most credulous. It is from 
 having had experience of the dishonesty of 
 men, and of the moti\ es that tempt them to 
 it, that we come to disbelieve or to distrust 
 what they say. In general, when we doubt 
 a man^s word, we have some reason for it. 
 We think that what he says is incredible in 
 itself; or, that there is some motive or 
 temptation which inclines him in the pre- 
 sent case to violate truth ; or, that he is not 
 a competent judge of the matter in which he 
 gives testimony ; or, lastly, we distrust him 
 now, because we know him to have been a 
 deceiver formerly. 
 
57 
 
 Faith in testimony often rises to abso» 
 lute certainty. Of places and persons we 
 never saw, and of which we know nothing 
 but from the testimony of others, we believe 
 many things as firmly as we believe our 
 own existence. This happens, when the 
 testimonies of men concerning such places 
 and persons, are so many, and so consistent, 
 that it seems impossible they should be fic- 
 titious. When a number of persons, not 
 acting in concert, having no interest to dis- 
 guise what is true, or to affirm what is 
 false, and who are competent judges of 
 what they testify, concur in making the 
 same report, it would be accounted folly to 
 disbelieve them, especially if what they tes- 
 tify be credible in itself. Even when three, 
 or when two witnesses, separately examin- 
 ed, having had no opportunity to concert a 
 plan beforehand, concur in the same decla- 
 ration, we believe them, though we have had 
 no experience of their veracity ; because we 
 V2 
 
58 
 
 know^ that in such a case their declara^ 
 lions would not be consistent, if they were 
 not true. In regard to an impossible thing, 
 we should not believe our own senses, nor 
 consequently human testimony. Miraculous 
 facts, however^ are not to be ranked with 
 impossibilities. To raise a dead man to 
 life, to cure blindness with a touch, to re- 
 move lameness, or a disease, by speaking a 
 word, are miracles : but to divine power as 
 easy, as to give life to an embryo, make the 
 eye an organ of sight, or cause vegetation to 
 revive in the spring. If it be asked, what 
 evidence is sufficient to establish the truth of 
 miraculous events such as these, we answer, 
 that every event admits of a proof from hu- 
 man testimony, which it is possible for a 
 sufficient number of competent witnesses to 
 see and to hear. 
 
59 
 
 CHAPTER 11. 
 
 Of Propositions^ and their Various Kinds. 
 
 A PROPOSITION is a judgment of the 
 mind expressed in words. Now as our 
 judgments include at least two ideas, one of 
 which is affirmed or denied of the other; so 
 must a proposition have terms answering to 
 these ideas. The idea^ of which we affirm 
 or deny, and of course the term ex-ressing 
 that idea, is called the subject of that pro- 
 position. Th'^ idea affirmed or denied, as 
 also the term answering to it, is called the 
 PREDICATE. Thus, in the proposition, God 
 is omnipotent^ — God is the subject, it being 
 of him that we affirm omnipotence ; and 
 omnipotent is the predicate, because we af- 
 
60 
 
 firm the idea^ expressed by that word, to 
 belong to God. And that word, in a pro- 
 position, which connects the subject and pre- 
 dicate together, is called the copula ; as in 
 the above mentioned proposition, where is-^^s 
 the copula, and signifies the agreement of 
 the ideas of God and omnipotence. But if 
 we mean to separate two ideas, then, be- 
 sides the copula we must also use some par- 
 tide of negation to express this repugnance. 
 Of this kind, the proposition, Man is not 
 perfect^ may serve as an example ; where 
 the idea of perfection b iog intended to be 
 separated from the idea of many the nega- 
 tive particle not is inserted after the copula, 
 to signify the disagreement between the sub- 
 ject and the predicate. But although every 
 proposition necessarily consists of these 
 three p<irts, it is not alike necessary that 
 they be all severally expressed in words; 
 because the copula is often included in the 
 term of the predicate, as when we say he 
 
61 
 
 writes^ which imports the same as he is 
 writing. And in the Latin language, a single 
 word has often the force of a whole sen- 
 tence ; where ambulat, for example, is the 
 same as ille est ambulans ; amo^ as ego sum 
 amans. 
 
 Propositions are either affirmative or 
 
 NEGATIVE^ UNIVERSAL or PARTICULAR, AB- 
 SOLUTE or CONDITIONAL, SIMPLE Or COM- 
 POUND, SELF-EVIDENT Or DEMONSTRABLE; 
 SPECULATIVE Or PRACTICAL. 
 
 An aflSrmative proposition connects the 
 predicate with the subject; as, A stone is 
 heavy: a negative separates them : as, God 
 is not the author of evil. And as, in all 
 cases, the predicate must either be connect- 
 ed with the subject, or separated from it, it 
 is evident that all propositions fall under 
 these two divisions. 
 
6a 
 
 An universal proposition is a proposition 
 which has for its subject some general lerrn 
 taken in its full extent; sa that tlie predicate 
 agrees with all the individuals comprehend- 
 ed under it, if it be a proper spec^ies, and 
 with all the several species and their indi- 
 viduals, if it be what is termed a genus. 
 Thus, Ml animals have a power of begin- 
 ning motion^ is an universal proposition ; 
 animalsp the subject being a general term 
 without any mark of limitation, and by con- 
 sequence taken in its full extent : hence the 
 power of beginning motion may be affirmed 
 of all the several species of animals, as of 
 quadrupeds, birds, insects, fishes, &e. ; and 
 of all the individuals of which these differ- 
 ent species consist, as of this hawk, that 
 horse, and so on with respect to the rest. 
 A particular proposition is one, which has, 
 in like manner, some general term for its 
 subject; but with a mark of limitation 
 
63 
 
 added, to denote that the predicate agrees 
 with some only of the individuais compre- 
 hended under it, if it be a species ; or with 
 one or more, not with all, of the species be- 
 longing to it, if it be a genus. Thus, Some 
 stones are heavier than iron — Some men 
 have an uncommon share of prudence. 
 Where the subject of a proposition is an in- 
 dividual, it is called a singular proposi- 
 tion. Of this nature are the follbwing. Sir 
 Isaac JSTewton was the inventor of fluxions— - 
 This book contains many useful truths. 
 And such propositions, though more parti- 
 cular than those which are generally called 
 so, come under the same rule with univer- 
 sals ; because, in them, the subject is takeu 
 in its full extent. 
 
 It has been already observed, that all 
 propositions are either affirmative or nega- 
 tive : it is equally evident, that, in both 
 cases, they may be universal or particular. 
 
6t 
 
 Hence arises that celebrated fourfold divi- 
 sion of them, into universal affirmative, 
 
 UNIVERSAL negative; PARTICULAR AFPIR- 
 MATIVE, and PARTICULAR NEGATIVE. And, 
 
 in forming syllo^^isms, it has become a cus- 
 torn, in the schools, to make use of the four 
 vowels, a, e, z, o, to denote these varieties : 
 a, to denote an universal affirmative, as. Ml 
 good men are esteemed ; e, an universal ne- 
 gative, as JSTo man is infallible ; z, a parti- 
 cular affirmative, as, Some men are wise; 
 Oy a particular negative, as Some men are 
 not honest.^ 
 
 The distinction of propositions into uni- 
 versal and particular, is called their quan- 
 TiTY ; and into affirmative and negative, 
 their quality* 
 
 ^ i6 Assent a, negat e, vei^mn generaliter ambce : 
 ^( Jsserit i, negat o, sed particulariter ambo.^^ 
 
m 
 
 Absolute propositions are those iti which 
 we affirm, that some property is inseparable 
 from the idea of the subject; as, Lead is 
 heavy. Conditional propositions are those 
 in which the predicate is not necessarily 
 connected with the subject, and can be af- 
 firmed of it on some condition only, distinct 
 from the idea of the subject ; as, if a stone 
 be exposed to the rays of the sun^ it will 
 contract a degree of heat. And here we 
 are to observe, that all conditional proposi- 
 tions consist of two distinct parts ; one ex- 
 pressing the condition upon which the pre- 
 dicate agrees or disagrees with the subject, 
 as, in the example before us, // a stone be 
 exposed to the rays of the sun ; the other, 
 joining or disjoining said predicate and sub- 
 jert, as, in the same example, It will con-^ 
 tract a degree of heat. The first of these 
 parts is called the antecedent; the second^ 
 the consequent. 
 
66 
 
 When a propositipn has but one subject 
 and one predicate^ it admits of no subdivi- 
 sion, and is said to be simple. When it 
 has more than one subject, or more than one 
 predicate ; or has several subjects and predi- 
 cates ; it is said to be compound. If it have 
 one subject and more than one predicate, or, 
 vice versap one predicate and more than one 
 subject, it may, in the one case, be resolved 
 into as many simple propositions as there 
 are predicates, and, in the other, into as 
 many as there are subjects ; as will be obvi- 
 ous from the following examples : The prac- 
 tice of swearing in common conversation^ 
 is absurd^ unmannerly^ and impious — JVei- 
 ther kings nor people are exempt from 
 death. Nor is it less evident, that if a pro- 
 position consists of several subjects and pre- 
 dicates, it may be resolved into as many 
 simple propositions, as there are subjects 
 and predicates. Compound propositions 
 
67 
 
 are of two kinds ; copulative and disjunctive. 
 A copulative proposition takes place, where 
 the subjects and predicates are so joined 
 together, that they raay be all severally af- 
 firmed or denied of each other. Of this na- 
 ture are the examples which have been just 
 given. A disjunctive proposition compares 
 several predicates with the same subject, 
 and affirms that one of them necessarily be- 
 longs to it, but without determining which ; 
 aS;, l^his world either exists of itself ^ or is 
 the work of some allivise and powerful 
 cause. It is the nature of all propositions 
 of this class, that, upon determining the par- 
 ticular predicate, the re^t are of course to be 
 removed; or, that if alj the predicates but 
 one be removed, that one necessarily takes 
 place: thus, in the example given ahuve^ if 
 we allow the world to be the work of some 
 wise and powerful cause, we of course deny 
 it to he self-existent ; or, if we deny it to be 
 self-existent, we must necessarily admit^ 
 
68 
 
 that it was produced by some wise and 
 powerful cause 
 
 A proposition is self-evident, when^ 
 without any investigation or proof, the truth 
 of it is obvious at first view. When we 
 affirm^ for instance, that a part of any thing 
 is less than the whole^ or that men exists and 
 other animals; whoever understands the 
 terms made use of, perceives at the first 
 view, the truth of what is asserted ; nor can 
 he, by any efforts, bring himself to believe 
 the contrary. A demonstrable proposition 
 is one, the truth of which does not immedi- 
 ately appear, but may be made to appear by 
 means of other propositions more known 
 and obvious, from which it follows as an 
 unavoidable consequence. 
 
 A speculative proposition affirms or de- 
 nies some property of its subject^ as when it 
 is affirmed; that the radii of a circle are all 
 
69 
 
 equal. A practical proposition asserts that 
 something may be done or effected : as, that 
 a right line may he drawn from one point 
 to another. And from this last distinction 
 arises a fourfold division of mathematical 
 propositions, into self-evident specula- 
 tive, and self-evident practical; de- 
 monstrable speculative, and demon- 
 strable PRACTICAL. Self-evident specu- 
 lative propositions are called axioms ; and 
 self-evident practical propositions, postu- 
 lates ; demonstrable speculative proposi^ 
 tions, THEOREMS : and demonstrable prac- 
 tical propositions/ problems. 
 
 eg 
 
70 
 
 PART III. 
 
 Of Reasoning. 
 
 The subject of this part of Logick is an 
 exteniive one; and to discuss it fully would 
 require much time. We shall content our- 
 selves with explaining what is meant by 
 reasoning, and giving some account of va- 
 rious kinds of syllogisms, which are acts of 
 reasoning expressed in words. To which 
 we shall subjoin such of the sophisms, or 
 false arguments^ as are the most remarka* 
 We. 
 
71 
 
 CHAPTER I. 
 
 Of Reasonings and the Parts of which it 
 consists. 
 
 It has been already observed, that, in 
 comparing two ideas together, it will some- 
 times happen, that their agreement or dis- 
 agreement cannot be immediately^ discern- 
 ed. In such cases it becomes necessary to 
 look out for some third idea, that will admit 
 of being compared with them, severally : 
 that is, first with one and then with the 
 other: that, by such comparison, we may 
 be enabled to see how far the ideas, with 
 
 * That is, without some medium^ or proof. 
 
73 
 
 which this third is compared, do, them- 
 selves, agree or disa2;ree. For it is a self- 
 evident truth, that, if two things agree with 
 a thirds they must agree with each other, 
 and that, if one of two things agree with 
 a third n and the other disagree with it, they 
 must disagree with each other. 
 
 From what has been said, it appears^ 
 that every act of reasoning necessarily in- 
 cludes three disrinct judgments : two, ia 
 which the ideas, the relations of which we 
 want to discover, are severally compared 
 with the middle idea: and a third, in which 
 they are themselves connected or disjoined, 
 according to the result of that comparison. 
 Now, as our judgments, when put into 
 words, are called propositions ; so our acts 
 of reasoning, when expressed by words, 
 are termed syllogisms. And hence it fol- 
 lows, that as every act of reasoning implies 
 three several judgments, so every syllogism 
 
' 73 
 
 must include three distinct propositions. 
 And when an act of reasoning is thus put 
 into words, and appears in the form of a 
 syllogism^ the intermediate idea made use 
 of to discover the agreement or disagree- 
 ment which we seek to investigate, is called 
 the MIDDLE, TERM ; and the two ideas them- 
 selves, with which this third is compared, 
 go hy the name of extremes. 
 
 But, as these things are best illustrated 
 by examples, let us suppose, that we have 
 set ourselves to enquire, whether men are 
 accountable for their actions. As the rela- 
 tion between the ideas of man and account-- 
 ablenesSf comes not within the immediate 
 view of the mind, our first care must be, to 
 find out some third idea that will enable us 
 to discover and trace it. A very small 
 measure of reflection is sufficient to inform 
 us, that no creature can be accountable for 
 bis actions, unless we suppose him capable 
 
74 
 
 of distinguishing those which are good from 
 those which are bad ; that is, unless we sup- 
 pose him possessed of reason. Nor is this 
 alone sufficient. For what would it avail 
 him to distinguish good from bad actions, 
 if he had no freedom of choice, and could 
 not pursue the one and avoid the other? 
 Hence it becomes necessary to take in both 
 these considerations in the present case. It 
 is at the same time equally evident, that 
 wherever there is this ability of distinguish- 
 ing good from bad actions, and pursuing 
 the one and avoiding the other, there also a 
 creature is acconntal>le. We have then got 
 a third idea, with which accountableness is 
 inseparably connected, namel;^, the idea of 
 a creature possessed of reason and liberty. 
 Let us now take this third or middle idea, 
 and compare it with the other idea in ques- 
 tion, namely man ; and we all know by ex- 
 perience, that it may be affirmed of him* 
 Having thus, by means of the intermediate 
 
75 
 
 idea, formed two several judgments, that 
 man is possessed of reason and liberty^ and 
 that reason and liberty imply accountable- 
 ness ; a third obviously and necessarily fol- 
 lows, naraelj^, that man is accountable for 
 his actions. 
 
 Here then we have a complete act of 
 reasoning, in which, according to what has 
 been already observed, there are three dis- 
 tinct judgments ; two, that may be styled 
 previous, in as much as they lead to the 
 other, and arise from comparing the middle 
 idea with the two ideas in question ; and a 
 third, which is a consequence of these pre- 
 vious acts, and flows from uniting the ex- 
 treme ideas themselves. If now we put 
 this act of rea*^oning into due form, it exhi- 
 bits what Logicians call a syllogism, and 
 runs thus : 
 
 Every creature^ possessed of reason and 
 liberty is accountable for his actions. 
 
76 
 
 Man is a creature possessed of reason and 
 liberty : 
 
 Therefore man is accountable for his 
 actions. 
 
 Of these three propositions, the two 
 first answer the two previous judgments, in 
 an act of reasoning; and are called the 
 PREMISES, because they are placed before 
 the other : the third is termed the con- 
 CLusiON ; as being gained in consequence 
 of what was asserted in the premises. Jlan 
 and accountableness are the extremes ; and 
 a creature possessed of reason and liberty^ 
 the middle term. 
 
 We may also observe, that, as the con- 
 elusion is made up of the extreme terms of 
 the syllogism, so that extreme, which serves 
 as the predicate of the conclusion, goes by 
 the name of the major term ; and the other 
 extreme, which makes the subject in the 
 
77 
 
 same proposition, is called the minor term. 
 And again, from this distinction between the 
 extremes arises also a distinction between 
 the premises, where these extremes are se- 
 verally compared with the middle term ; 
 that proposition which compares the major 
 term, or the predicate of the conclusion, 
 with the middle term, being called the 
 MAJOR proposition ; the other, wherein the 
 same middle term is compared with the sub- 
 ject of the conclusion or minor term, being 
 called THE MINOR PROPOSITION. To which 
 may be added, that, when a syllogism is 
 proposed in due form, the major proposition 
 is always placed first, the minor next, and 
 the conclusion last. 
 
 These things premised, we may define 
 reasoning to be, Jin act or operation of the 
 mind, deducing some proposition^ the truth 
 of which was before unknown^ from other 
 previous ones that are either self-evident or 
 
 H 
 
78 
 
 such as have been fully proved and esta- 
 hlished. These previous propositions, in a 
 simple act of reasoning, are only two in 
 number ; and, in order to afford an unques- 
 tionable conclusion, must be intuitive propo- 
 sitions. When they are not so, previous 
 syllogisms are required : in which case rea- 
 soning becomes a complicated act, taking in 
 a variety of successive steps* If, for exam- 
 ple, in the major of the syllogism given 
 above, viz. Every creature possessed of 
 reason and liberty is accountable for his ac- 
 tions^ the connexion between the subject and 
 predicate could not be perceived by the 
 mere attention of the mind to the ideas 
 themselves, ii is evident that this propsi- 
 tion would no less require proof than the 
 conclusion deduced from it. In this case, a 
 new middle term must be sought for, to 
 trace the connexion here supposed ; and 
 this of course, furnishes another syllogism ; 
 by which having established the proposition 
 
79 
 
 in question, we are then, and not before, at 
 liberty to use it in any succeeding act of 
 reasoning; And should it so happen, that, in 
 the second syllogism, there were still some 
 previous proposition, the truth of which did 
 not appear at first sight, we must then have 
 recourse to a third syllogism, in order to lay 
 open that truth to the mind ; because, so 
 long as the premises remain uncertain, the 
 conclusion, built upon them, must be so toOo 
 And when, by conducting our thoughts in 
 this manner, we at last arrive at some syllo- 
 gism where the previous propositions are in* 
 tuitive truths, the mind then rests in full se- 
 curity ; as perceiving, that the several con- 
 elusions, which it has passed through, stand 
 upon the immoveable foundation of self-evi- 
 dence, and when traced to their source, ter- 
 minate in it. 
 
 And here, if, after having thus unravel- 
 led a demonstration, we take it the contrary 
 
80 
 
 way, and observe how the mind, setting out 
 with intuitive propositions, connects them 
 together to form a conclusion ; how, by in- 
 troducing this conclusion into another syl- 
 logism, it still advances one step farther; 
 and so proceeds, making every new disco- 
 very subservient to future progress ; we 
 shall then perceive clearly, that reasoning, 
 in the highest exercise of that faculty, is no 
 more than an orderly combination of those 
 simple acts which we have already so fully 
 explained. And we shall also perceive, 
 that all the knowledge acquired by reason- 
 ing, how far soever we may carry our disco- 
 veries, is still built upon our intuitive judg- 
 ments ; every discovery of human reasoning 
 being the consequence of a syllogism, the 
 premises of which are self-evident proposi- 
 tions, or of a train of syllogisms, which, 
 when traced to their source, always termi- 
 nate in them 
 
81 
 
 Men reason, either to rank things un- 
 der those universal ideas to which they 
 truly belong, or to ascribe to them their 
 several attributes and properties in conse» 
 quence of that distribution. 
 
 !• One great end for which men reason^ 
 is to rank things under those universal 
 ideas to which they belong; or, in other 
 words, to determine the genera and species 
 of things. We have seen, in the first part 
 of this treatise, how the mind proceeds in 
 forming general ideas. We have also seen, 
 in the second part, how, by means of these 
 general ideas, we form universal proposi* 
 tions. Now, as in universal propositioug^ 
 we affirm some property of a genus or spe- 
 H3 
 
82 
 
 cies, it is plain, that we cannot apply this 
 prop»-rty to particular olyects, till we have 
 first determined whether they are compre- 
 hended under that general idea of which the 
 property is affirmed. Thus, there are cer- 
 tain properties belonging to all even numbers, 
 which nevertheless cannot be applied to any 
 particular number, until we have first dis- 
 covered it to be of the species expressed by 
 that general name. Hence, reasoning be- 
 gins by referring things to their several di- 
 visions and classes in the scale of our ideas : 
 and, as these divisions are all distinguished 
 by peculiar names, we hereby learn to ap- 
 ply the terms expressing general concep- 
 tions, to such particular objects as come un- 
 der our immediate observation. 
 
 In order to arrive at these conclusions, 
 by which the several olyects of perception 
 are brought under general names, two things 
 are manifestly necessary. First, that we 
 
83 
 
 take a view of the idea itself denoted by 
 that ^^eneral name, and carefully attend to 
 the distinguishing marks which serve to 
 characterise it. Secondly, that we compare 
 this idea with the object under considera- 
 tion, observing diligently wherein they 
 agree or dijBFer. If the idea be found to 
 correspond with the particular object, we 
 then without hesitation apply the general 
 name ; but, if no such correspondence ap- 
 pear, the conclusion must necessarily take 
 a contrary turn. Let us, for instance, take 
 the number eighty and consider by v/hat 
 steps we are led to pronounce it an even 
 number. First, we call to mind the idea 
 signified by the expression, an even num- 
 ber ; namely, that it is a number divisible 
 into two equal parts : we, then, compare 
 this idea with the number eight ; and, find- 
 ing them manifestly to agree, we see at once 
 the necessity of admitting the conclusion. 
 
84 
 
 These several judgments^ therefore, trans- 
 ferred into language, and reduced to the form 
 of a syllogism, appear thus : 
 
 Every number that may be divided into 
 two equal parts^ is an even number : 
 
 The number eight may be divided into 
 two equal parts : 
 
 Therefore the number eight is an even 
 number. 
 
 It may be observed, indeed, that where 
 the general idea, to which particular objects 
 are referred, is very familiar to the mind, 
 and frequently in view, this reference, and 
 the application of the general name, seem 
 to be made without any reasoning. When 
 we see a horse in the fleld^, or a dog in the 
 street, we readily apply the name of the 
 species; habit, and a familiar acquaintance 
 with the general idea, suggesting it instan- 
 
85 
 
 taneously to the mind. We are not, how- 
 ever, to imagine, on this account, that the 
 understanding departs from the usual rules 
 of just thinking. A frequent repetition of 
 acts begets a habit; and habits are attended 
 with a certain promptness of execution, that 
 prevents our observing the several steps and 
 gradations, by which any course of action is 
 accomplished. But, in other instances, 
 where we judge not by pre-contracted ha- 
 bits; as when the general i^l^a is very com- 
 plex, or less familiar to the mind ; we al- 
 ways proceed according to the form of rea- 
 soning established above. A goldsmith, 
 for instance, who is in doubt as to any piece 
 of metal, whether it be of the species called 
 gold J first examines its properties ; and, then 
 comparing them with the general idea sig- 
 nified by that name, if he find a perfect cor- 
 respondence, no longer hesitates under what 
 class of metals to rank it. Now what is 
 this, but following step by step those rules 
 
86 
 
 of reasoning \vhich we have before laid 
 down, as the standards by which to regu- 
 late our thoughts in all conclusions of this 
 kind? 
 
 Nor let it be imagined, that our re- 
 searches here/ because in appearance bound- 
 ed to the imposing of general names upon 
 particular objects, are therefore trivial and 
 of little consequence. Some of the most 
 considerable debates among mankind, and 
 such too as nearly regard their lives, inter- 
 est, and happiness, turn wholly on this ar- 
 ticle. Of what importance, for instance, is 
 it, in many cases, to decide aright whether 
 an action is to be termed murder or man- 
 slaughter? We see, no less than the lives 
 and fortunes of men depend often upon these 
 decisions. The reason is plain. Actions, 
 when once referred to a general idea, draw 
 after them all that may be aflBrmed of that 
 idea ; insomuch, that the determining of the 
 
87 
 
 species of actions, is the same with deter^ 
 mining what proportion of praise or dis- 
 praise, commendation or blame, &c., ought 
 to follow them. For, as it is allowed that 
 murder deserves death, by bringing any- 
 particular action under the head of murder, 
 we of course decide the punishment due 
 to it. 
 
 2. The other great aim which men 
 have in view in their reasonings, is, the dis« 
 covering and ascribing to things their seve=. 
 ral attributes and properties. And here it 
 will be necessary to distinguish between rea- 
 soning, as it regards the sciences, and as it 
 concerns common life. In the sciences, our 
 reason is employed chiefly about universal 
 truths, it being by them alone, that the 
 bounds of human knowledge are enlarged. 
 Hence the divisions of things into various 
 classes, called genera and species. For 
 these universal ideas being set up as the re 
 
88 
 
 presentatives of many particular things, 
 whatever is affirmed of them, may be also 
 affirmed of all the individuals to which 
 they belong, Murder^ for instance, is a 
 general idea, representing a certain species 
 of human actions. Reason tells us, that the 
 punishment due to it is death. Hence every 
 particular action coming under the idea of 
 inurder^ has the punishment of death allot- 
 ted to it. Here, then, we apply the general 
 truth to some obvious instance, and this is 
 what properly constitutes the reasoning of 
 common life. For men in their ordinary 
 transactions and intercourse one with the 
 other, have for the most part to do only 
 with particular^i objects. 
 
 Hence it appears, that reasoning, as it 
 regards common life, is no more than the 
 ascribing of the general properties of things 
 to those several objects with which we are 
 immediately concerned, according as they 
 
89 
 
 .re found to be of that particular division or 
 class^ to which the properties belong. The 
 steps by which we proceed are manifestly 
 these. Firsts we refer the object under con- 
 sideration to some general idea of class of 
 things ; we then recollect the several attri- 
 butes of that general idea ; and, lastly^ 
 ascribe all those attributes to the present 
 object. Thus^ in considering the character 
 of Sempronius^ if we find it to be of the 
 kind called virtuous ; when we at the same 
 time reflect, that a virtuous character is 
 deserving of esteem ; it naturally and obvious- 
 ly follows, that Sempronius deserves esteem. 
 These thoughts put into a syllogism, in or» 
 der to exhibit the form of reasoning here re- 
 quired, run thus : 
 
 Every virtuous man is deserving of esteem: 
 Sempronius is a virtuous man : 
 Therefore^ Sempronius is deserving of es^ 
 teem, 
 
 I 
 
90 
 
 From this syllogism it appears, that be- 
 fore we affirm any thing of a particular ob- 
 ject, that object must be referred to some 
 general idea. Sempronius is pronounced 
 worthy of esteem, only in consequence of 
 his being a virtuous man, or coming under 
 that general idea. Hence we see the neces- 
 sary connexion of the various parts of rea- 
 soning, and the dependence they have, one 
 upon another. The determining of the ge- 
 nera and species of things is an exercise of 
 human reason ; and this exercise is the first 
 in order and previous to the other, which 
 consists in ascribing to them their powers, 
 properties, and relations. But when we 
 have taken this previous step, and brought 
 particular objects under general names ; as 
 the properties we ascribe to them are no 
 other than those of the general ideau, it is 
 plain, that, in order to a succeswjful progress 
 in this part of knowledge, we must fho- 
 roughly acquaint ourselves with the several 
 
91 
 
 relations and attributes of these our general 
 ideas. When this is done, the other part 
 will be easy and require scarce any labour 
 of thouglit, as being no more than an appli^ 
 cation of the general form of reasoning re* 
 presented in the foregoing syllogismo 
 
92 
 
 CHAPTER II 
 
 Of Syllogisms 
 
 Syllogisms may be divided into single 
 and COMPOUND. Single syllogisms are 
 those which consist of three propositions^ 
 and no more. Compound syllogisms are 
 those which consist of more than three pro- 
 positions^ and may be formed into two or 
 more syllogisms. 
 
 Of Single Syllogisms. 
 
 Single syllogisms may be divided into 
 several sorts ; of which the most important 
 are simple or categokical, conditional^ 
 and DISJUNCTIVE. 
 
93 
 
 Those are properly called Simple, or 
 Categorical, syllogisms, which are made up 
 of three plain, simple, or categorical propo- 
 sitions ; iQ which, the middle term is joined 
 with one part of the question in the major 
 proposition, and with the other in the minor. 
 
 And here, to guard us against false iri« 
 ferences, certain rules have been found ne* 
 cessary, which depend on the four following 
 axioms. 
 
 1. Particular propositions are contained 
 in universals, and may be inferred from 
 them; but universals are not contained ia 
 particulars, and cannot be inferred from 
 them. 
 
 S. In all universal propositions, the sub- 
 ject is universal ; in all particular proposi« 
 tions, the subject is particular, 
 IS 
 
94 
 
 3, In all aflBrmative propositions, the 
 predicate has no greater extension than the 
 subject; for its extension is restrained by 
 the subject : and therefore it is always to be 
 esteemed as a particular idea. It is by 
 mere accident, if ever it be taken univer- 
 sally ; and cannot happen, but in such uni- 
 versal or singular propositions as are reci- 
 procal.* 
 
 4^. The predicate of a negative proposi- 
 tion is always taken universally : for in its 
 whole extension, it is denied of the subject. 
 If we say, JSTo stone is vegetable^ we deny 
 all sorts of vegetation concerning stones. 
 
 * A proposition is said to be reciprocal, when 
 the subject and the predicate may mutually in- 
 terchange their places with preservation of the 
 truth. 
 
95 
 
 The rules are these : 
 
 1. The middle term must not be taken 
 twice particularly^ but once at least univer- 
 sally. For if the middle term be taken for 
 two different parts or kinds of the same uni- 
 versal idea, then the subject of the conclu- 
 sion, or minor extreme, is compared with 
 one of these parts, and the predicate, or 
 major extreme, with the other part^ and this 
 will never show whether that subject and 
 predicate agree or disas^ree ; for there will 
 then be four distinct terms in the syllogism, 
 and the two parts of the question, that is, 
 the two extremes, will not be compared with 
 the same third idea, 
 
 2. The terms^ in the conclusion, must 
 never be taken more universally than they 
 are in the premises. The reason is deriv- 
 ed from the first axiom, that generals can 
 never be inferred from particulars. 
 
96 
 
 3. .5 negative concliinon cannot be 
 proved by two affirmative premises. For, 
 when the two terms of the conclusion are 
 united, or asjr^e with the middle term, it 
 does not by any means follow that they dis- 
 agree with one another. 
 
 4. If one of the premises be negative^ 
 the conclusion must be negative. For if the 
 middle term be denied of either part of the 
 conclusion, it may show that the terms of 
 the conclusion disagree, but it can never 
 show that they agree. 
 
 5. If either of the premises be particu- 
 lar^ the conclusion must be particular. 
 This may be proved from the first axiom. 
 These two last rules are sometimes united 
 in this single sentence, The conclusion al- 
 ways follows the weaker part of the premi- 
 ses. For negatives and particulars are ac 
 
97 
 
 counted inferior to affirmatives and univer- 
 sals. 
 
 6. From two negative premises ^ nothing 
 can be concluded. For they separate the 
 middle term both from the subject and the 
 predicate of the conclusion ; and when two 
 ideas disagree with a third, we cannot infer 
 that they either agree or disagree with each 
 other. 
 
 7. From two particular premises^ no- 
 thing can he concluded. This rule de- 
 pends chiefly on the first axiom. 
 
 In forming syllogisms, especially those 
 of which we are now treating^ we make use 
 of FIGURES and moods. By the Figure of a 
 syllogism, is m^ant the peculiar way in 
 which the middle term is connected with 
 the extremes. By the Moods belonging to a 
 figure^ are meant, the several ways in which 
 
98 
 
 the propositions of one syllogism may differ 
 from tiiose of another, belonging to the same 
 figure, as to quantity and quality ; that is, as 
 to their being universal or particular, affir^ 
 mative or negative. 
 
 Figures are usually reckoned three. In 
 the. jirst^ the middle term is the subject of 
 the major, and the predicate of the minor, 
 proposition. In the second^ it is the predi- 
 cate of both these propositions ; and, in the 
 thirdp the subject.^ 
 
 The moods, belonging to each of these 
 figures, are signified by certain artificial 
 words, in which the consonants are neglect- 
 ed, and the vowel only regarded ; a, denot- 
 ing, as was before observed, an universal 
 
 Sub prccy primse; bis pro?, secundae; tertisc* 
 bis sub. 
 
99 
 
 affirmative ; e, an universal negative ; z, a 
 particular affirmative ; and o^ a particular 
 negative. And to assist the memory in re- 
 taining these words, they are comprised in 
 four Latin verses* 
 
 Barbara^ Celarent^ Baviiy Ferio quoque, 
 
 primse:^ 
 CesarCf Camestres^ Festino^ JBaroco^ se- 
 
 cundsB : 
 Tertia, Darapti sibi vindicat atque Felap- 
 
 ton J 
 Adjungens Disamis^ JDatisi^ Bocardo^ Fe- 
 
 rison. 
 
 Bar- All wicked men are miserable : 
 
 BA- Tyrants are wicked men : 
 
 RA. Therefore tyrants are miserable. 
 
100 
 
 Ce- No practice, inconsistent with the 
 Christian law of charity^^ can be 
 innocent. 
 
 LA- The practice of reducing men, of any 
 colour, to a state of slavery, is 
 inconsistent with the Christian 
 law of charity. 
 
 RENT. Therefore the practice of reducing 
 men, of any colour, to a state of 
 slavery, cannot be innocent. 
 
 Da- Whatsoever furthers our salvation 
 is good for us : 
 
 Bi- Some afflictions further our salva- 
 tion : 
 
 I. Therefore some afflictions are good 
 
 for us. 
 
 ^ Wliatsoever ye would that men should do to 
 you, do ye even so to them. — Matt. vii. 12. 
 
101 
 
 Fe. JK'^otliing that must be repented of) 
 
 is desirable : 
 III- Sinful pleasures must be repented 
 
 of-- 
 o. Therefore sinful pleasures are not 
 
 desirable. 
 
 It is the excellence of this figure, that 
 all questions may be proved by it, whether 
 universal or particular, affirmative or nega- 
 tive. 
 
 In the second figure also, there are four 
 moods ; but it admits of negative conclusions 
 onlv. 
 
 K 
 
102 
 
 Ce. No one, who is either a good Chris- 
 tian, or a good citizen, can delibe. 
 rately resolve to do what the laws 
 of God and his country forbid : 
 
 SA- A duellist deliberately resolves to do 
 what the laws of God and his coun- 
 try forbid : 
 
 BE. Therefore no duellist can be, either a 
 good Christian, or a good citizen. 
 
 Ca- Every man of strict honour would 
 disdain to enrich himself at his 
 neighbour's expense : 
 
 MES- No gamester disdains to enrich him- 
 self at his neighbom^^s expense : 
 
 TRES. Therefore no gamester is a man of 
 strict honour. 
 
103 
 
 Fes- No sins are excusable : 
 
 Ti- Anger, upon some occasions, is ex- 
 cusable : 
 
 NO. Therefore anger, upon some occa- 
 sions, is not a sin. 
 
 Bal- Every true patriot will seek to jpro- 
 mote peace and concord among hi^ 
 fellow citizens : 
 
 KG- Some, who profess to be patriots, do 
 not seek to promote concord and 
 peace among their fellow -citizens. 
 
 CO. Therefore some^ who profess to be 
 patriots, are not true patriots. 
 
 In the third figure, there are six moods | 
 and the conclusion is always particular. 
 
 Da- All good Christians shall be saved : 
 ^RAP- Jill good Christians have sinned : 
 TTo Therefore some, who have sinned^ 
 shall be saved 
 
104 
 
 Fe- No hyiiocrites are jileasing to God : 
 LAP- All hypocrites seem to be religious : 
 TON. Therefore some, who seem to be re- 
 ligious^ are not pleasing to God. 
 
 Di- Some selfish and turbulent men make 
 very violent pretensions to patri- 
 otism : 
 
 SA- All selfish and turbulent men are 
 destitute of any real love for their 
 country : 
 
 MIS. Therefore some, who are destitute of 
 any real love for their country, 
 make very violent pretensions to 
 patriotism. 
 
105 
 
 Da- All honest men are entitled to our 
 love and esteem : 
 
 Ti- Some honest men differ very widely 
 from us in their sentiments with 
 resp(^ct to religion and politics : 
 
 ^i. Therefore some, who differ very 
 widely from us in their sentiments 
 v/ith respect to religion and poli- 
 tics, are entitled to our love and 
 esteem. 
 
 Bo- Some wars d¥e not to be avoided : 
 CAR. All tvars produce blood-shed : 
 DO. Therefore some blood-shed is not to 
 be avoided* 
 
 Fe- No afflictions are pleasant : 
 HI- Some afflictions are good for us : 
 SON. Therefore some things, which are 
 good for us, tne not pleasant. 
 
 K2 
 
106 
 
 The special rules of the three fi2;nres 
 are these. In the first, the major proposi- 
 tion must always he universaL and the mi- 
 nor affirmative. In the second, the major 
 must also be universal^ and one of the pre^ 
 miiies^ together with the conclusion^ must he 
 negative. — In the third, the minor must he 
 affirmative^ and the conclusion always par- 
 ticular. 
 
 There is also a fourth; in which the 
 middle terra is the predicate of the major 
 proposition, and the subject of the minor. 
 But this, being a very indirect and ohlique 
 manner of concluding, is never used in the 
 sciences, or in common life ; and is, conse- 
 quently, useless. 
 
 A Conditional or Hypothetical Syllogism 
 is a syllogism of which the major is a con- 
 ditional or hypothetical proposition ; as, 
 
107 
 
 If there be a God he ought to be wor- 
 
 shipped : 
 
 But there is a God : 
 
 Therefore he ought to be worshipped. 
 
 And here it is * to be observed, that^ in 
 all proposition'^ of this kind, the antecedent 
 must alwayn contain some certain and ge- 
 nuine condition, which necessarily implies 
 the consequent ; for otherwise the proposi- 
 tion itself will be false, and therefore ought 
 not to be admitted into our reasonings. 
 Hence it follows, that, when any condi- 
 tional proposition is assumed, if we admit 
 the antecedent of that proposition, we must 
 at the same time necessarily admit the con- 
 sequent; but that, if we reject the conse- 
 quent, we must in like manner necessarily 
 reject the antecedent. It appears then^ 
 that; in conditional syllogisms, there 
 
lOS 
 
 are two ways of arguing which lead to a 
 certain and nnavoidahle conclusion, 1. 
 From the admission of the antecedent, to 
 the admission of the consequent : which con- 
 stitutes the mood or species of h^pothetipal 
 syllogisms, distinguished in the schools by 
 the name of the modus ponens ; inasmuch 
 as by it t^e whole cnnditional proposition is 
 established. And, of this mood, the syllo- 
 gism given above is an example, 3. From 
 the removal of the consequent, to the remo- 
 val of the antecedent: which constitutes the 
 mood or speries called by Logicians the 
 MODUS TOLLENS, b^cause by it both antece- 
 dent and consoqunnt are rejected; as ap- 
 pears by the following example. 
 
 If the sun he risen, the night is past : 
 
 But the night is not past: 
 
 Therefore the sun is not risen. 
 
109 
 
 These two species take in the whole 
 class of conditional syllogisms, nd include 
 all the possible ways of arguing which lead 
 by them to a legitimate conclusion ; because 
 we cannot here proceed by a contrary pro- 
 cess of reasoning, that is, from the removal 
 of the antecedent to the removal of the con- 
 sequent, or from the establisliing of the con- 
 sequent to the establishing of the antecedent. 
 For although the antecedent always ex- 
 presses some real condition, which once ad- 
 mitted, necessarily implies the consequent, 
 yet it does not follow that there is therefore 
 no other condition ; and if so, then, after re- 
 moving the antecedent^ the consequent may 
 still hold, because of some other condition 
 which implies it. When we say. If a stone 
 be exposed for some time to the rays of the 
 sun^ it will contract a degree of heat ; the 
 proposition is certainly true, and admitting 
 the antecedent we must admit the conse» 
 quent. But^ as there are other ways by 
 
110 
 
 which a stone may contract a degree of 
 heat^ it will not follow^ from the absence 
 of the before mentioned condition, that 
 therefore the consequent cannot take place. 
 In other words, we cannot argue, But this 
 stone has not been exposed to the rays of the 
 sun; therefore it has not contracted a degree 
 of heat; inasmuch as there are other ways, 
 by which lieat might have been contracted 
 by it. And as we cannot argue from the 
 removal of the antecedent to the removal 
 of the consequent, no more can we argue 
 from the adcoission of the consequent to the 
 admission of the antecedent. Because, as 
 the consequent may flow from a variety of 
 causes, the allowin^^ of it does not deter- 
 mine the precise cause, but only that there 
 must have be^Mi some on* of them. Thus, 
 in the foregoing proposition, If a stone be 
 composed for some time to the rays of the sun^ 
 it will contract a des^ree of heat. — admitting 
 the consequent, namely, thatzi has contract 
 
Ill 
 
 ed a degree of heatj we are not therefore 
 bound to ad J lit the antecedent^ that it has 
 for some time been exposed to the rays of 
 the sun ; inasmuch as there are other causes 
 whence that heat may have proreeded. 
 Tiiese two ways, therefore, of arguing^ hold 
 not in conditional syllogisms : except, in- 
 deed, where the antecedent expresses the 
 only condition; which is a case that hap- 
 pens but seldom, and cannot be extended to 
 a general rule. 
 
 A disjunctive syllogism is a syllogism of 
 which the major is a disjunctive proposition: 
 as in the following example. 
 
 The world is either self existent, or the 
 work of some finite, or of some infinite being: 
 
 But it is not self existent^ or the work of 
 a finite being: 
 
 Therefore it is the work of an infinite 
 being. 
 
lis 
 
 Now a disjunctive proposition is that, in 
 which, of several predicates, we aflRrm one 
 necessarily to belong to the subject, to the 
 exclusion of all the rest; but leave that par- 
 ticular one undetermined. Hence it fol- 
 lows, that, as soon as we determine the par- 
 ticular predicate, all the rest are of course 
 to be rejected ; or if we reject all the predi- 
 cates but one, that one necessarily takes 
 pl^ce. When therefore, in a disjunctive 
 syllogism, the several predicates are enu- 
 merated in the major, if the minor establish- 
 es any one of these predicates, the con ^- 
 gion ought to remove all (he rest; or if in 
 the minor, all the predicates but one are re- 
 moved, the conclusion must necessarily es- 
 tablish that one. Thus, in the disjunctive 
 syllogism given above, the major affirms one 
 of three predicates to belong to the world; 
 namely, that it is self existent^ or that it is 
 the wo7*k of a finite^ or that it is the work of 
 an ivjinite being; two of thesf' predicates 
 
113 
 
 are removed in the minor ; namely^ self- 
 existence^ and the work of a finite being: 
 hence the conclusion necessarily ascribes to 
 it the third predicate, and affirms that it is 
 the work of an infinite being. If now we 
 give the syllogism another turn, so that the 
 minor mn,y establish one of the predicates, 
 by affirming the world to be the production 
 of an infinite being; then the conclusion 
 must remove ^he other two ; by affirming it 
 to be neither self existent^ nor the work of 
 a finite being. These are the forms of rea- 
 soning in this species of syUogisms ; the 
 justness of which appears at first sight; and 
 that there can be no other, is evident from 
 the very nature of a disjunctive proposition. 
 
114 
 
 In the several kinds of syllogisms hi- 
 therto lueotioned, the parts, it may be ob- 
 served, have always been complete ; that is, 
 the three propositions, of which they con- 
 sist, have been always expressed. But it 
 often happens, that one of the premises is a 
 truth, not only evident, but also familiar, 
 and in the minds of all men ; in which case, 
 it is generally omitted : and by this means 
 we have an imperfect syllogism, which 
 seems to be made up of only two proposi- 
 tions. Should we, for instance, argue in 
 this manner, 
 
 God is our Creator^ 
 
 Therefore he must be worshipped : 
 
115 
 
 the syllogism appears to be imperfect, as 
 consisting but of two propositions : yet it is, 
 in reality, complete ; except that the major, 
 Our Creator must be worshipped^ is omit- 
 ted, and left to the reader to supply as a 
 propositions so familiar and evident, that it 
 cannot escape him. And these seemingly 
 imperfect syllogisms are called enthy° 
 
 MEMES. 
 
 And here, as enthymemes are the only 
 modes of reasoning which are in general 
 use, it may not be improper to take some 
 notice of their various forms. 
 
 Sometimes the reasoning proposition, 
 that is, the proposition expressed, as the 
 foundation of the conclusion, is placed first; 
 and the conclusion follows, with the sign of 
 reasoning prefixed to it; as in the foregoing 
 example : and this form constitutes, what, 
 
116 
 
 for the sake of distinction, may be called 
 
 the REGULAR ENTHYMEME. 
 
 \ 
 
 Another form, termed by a late writer* 
 the OBVIOUS ENTHYMEME, resembling the 
 preceding, but yet somewhat different from 
 it, is, where the reasoning proposition is in 
 like manner placed first, and the conclusion 
 after it; but with the sign of reasoning pre- 
 fixed, not to the latter, but to the former : for 
 example^ 
 
 Since for as J God is our Creator ^ 
 He must be worshipped. 
 
 A third form, which is termed the cau- 
 sal ENTHYMEME, is that, in which the rea- 
 soning proposition, with the sign of reason- 
 
 ^ Mr. Collard. 
 
117 
 
 ing prefixed to it, follows the conclusion | 
 thus, 
 
 God must be worshipped ; 
 Because he is our Creator.^ 
 
 ^ To these tlie writer, above aHuded to, has 
 added a fourth, which he calls the HYPOXHEXiCAii 
 
 ENTHYMEME ; aS, 
 
 If God be our Creator ^ 
 He must be worshipped 
 
 Here, according to our author, there is a con- 
 clusion gained, that God must be worshipped; found- 
 ed on a supposition, which, though not express- 
 ed, is understood, and supposed to be obvious^ 
 naraely, that our creator must be worshipped: 
 And, when this supposition is expressed, the act 
 of reasoning will assume the form of a sj'Hogism, 
 Thus, 
 
 L S 
 
118 
 
 But whatever be the form of the enthy- 
 meme^ it will be easy for the reader to sup- 
 ply what is wanting, and to convert any 
 
 Our Creator must be worshipped ; 
 
 If God be {that is, admit that God is) otir Crea- 
 tor : 
 
 {Jind you cannot but admits that) He must be 
 worshipped. 
 
 And this enthymeme, as he terms it, though it 
 has hitherto been called, by all writers on the 
 subject, a proposition, is, he contends, one of the 
 most common, and, certainly one of the most 
 useful, forms of reasoning in the compass of lan- 
 guage. 
 
 But, be this as it may, he very justly cautions 
 us against supposing, that any two propositions, 
 one taken conditionally and the other positively, 
 will form an hypothetical enthymeme; which can- 
 
119 
 
 such act of reasoning into a regular syllo- 
 gism. For he has only to ask himself, 
 upon what supposition the conclusion^ 
 which is drawn from the reasoning propo- 
 sition, depends ; and when this supposition, 
 which is always an obvious one, is once 
 
 not be, unless the attributes which should consti- 
 tute the major and middle terms^ that is, unless 
 the predicate of the conditional proposition and 
 the predicate of the positive proposition, be such 
 as universally agree, or universally disagree, with 
 each other. These propositions, for example^ 
 
 If I had leisure, 
 
 I would dedicate much time to study, 
 
 do not constitute an act of reasoning ; because it 
 is not an universal fact, that every one, who has 
 leisure, would, or would not, dedicate much time 
 to study. 
 
120 
 
 difsicoverecl, it will be tlie proposition omit- 
 ted. For example, 
 
 God is our Creator : 
 
 Therefore he is to be worshipped. 
 
 Upon what supposition does this conclnsion 
 depend ? Evidently upon this ; that our 
 Creator is to be worshipped Let this sup- 
 position then be expressed, and the syllo- 
 gism is complete. 
 
 Our creator is to he worshipped : 
 
 G(d is our Creator : 
 
 Therefore God is to be worshipped. 
 
121 
 
 But there is another species of reason- 
 ing with two propositions, which seems to 
 be complete in itself, and where we admit 
 the conclusion without any tacit or suppos- 
 ed judgment in the mind, from which it fol- 
 lows syllogistically* This happens be- 
 tween prop ^sitions where the connexion is 
 such, that the admission of the one, neces- 
 sarily, and at the first sight, implies the ad- 
 mission of the other. For if it so happen, 
 that the proposition on which the other de- 
 pends is self-evident, we content ourselves 
 with barely affirming it, and infer the other 
 by a direct conclusion. Thus by admitting 
 an universal proposition, we are forced also 
 to admit of all the particular propositions 
 comprehended under it, this being the very 
 
condition that constitutes a proposition uni- 
 versal. If then, that univerisal proposition 
 chances to be self-evident, the particular 
 ones follow of course, without any farther 
 train of reasoning. Whoever allov/s, for in- 
 stance, that things equal to one and the 
 same things are equal to one another^ must 
 at the same time allow, that two triangles^ 
 each equal to a square whose side is three 
 inchesj are equal to one another. This ar- 
 gument therefore^ 
 
 Things equal to one and the same thing, 
 are equal to one another ; 
 
 Therefore thege two triangles, each 
 equal to the square of a line of three inches, 
 are equal to one another ; 
 
 is complete in its kind, and contains all that 
 is ne<essary towardj^ a just and legitimate 
 conclusion. For the first or universal pro- 
 position is self-evident, and therefore re- 
 
quires no farther proof. Anil as the truth 
 of the particular is inseparably connected 
 with that of the universal, it follows from 
 it by an obvious and unavoidable conse- 
 quence. 
 
 Now in all cases of this kind, where 
 propositions are deduced one from another 
 on account of a known and evident connex- 
 ion, we are said to rea^^on by immediate 
 CONSEQUENCE. It is truc, that these argu- 
 ments may be considered as enthymemes, 
 who^e major propositions are wanting. — 
 The argument, for instance, but just men- 
 tioned, when represented according to this 
 view will run as follows: 
 
 1^ things equal to one and the same 
 thins;, are equal to one another^ these two 
 triangles, each equal to a square whose 
 side is three inches^ are also equal to one 
 another : 
 
But things equal to one and the same 
 things are equal to one another : 
 
 Therefore also these triangles^ Sfc. 
 are equal to one another. 
 
 But then it is peculiar to them, thtit the 
 ground upon which the conclusion restS;, 
 namely, its coherence with the minor, is of 
 itself evident, and seems immediately to fol- 
 low from the rules and reasons of iosrick. 
 As it is therefore entirely unnecessary to ex- 
 press a self-evident connexion, the major, 
 whose office that is, is constantly omitted ; 
 nay, and seems so very little needful to en- 
 force the conclusion, as to be accounted no 
 part of the argument. 
 
125 
 
 Of Compound Syllogisms. 
 
 A Compound Syllogism consists, as was 
 before observed, of more than three propo- 
 sitions, and may be resolved into two or 
 more syllogisms. The chief of these are 
 the EpiCHiREMA, Dilemma, Prosyllogism, 
 Sorites, and Induction of particulars. 
 
 Epichirema is a syllogism, in which we 
 prove the major, or the minor, or both, be- 
 fore we draw the conclusion : as, 
 
 Sickness may be good for us ; because it 
 brings us to consider our ways : 
 
 But we are uneasy under sickness; as 
 appears from our sighs^ groans^ and com- 
 plaints: 
 
 M 
 
126 
 
 Therefore we are sometimes uneasy^ 
 under what is good for us. 
 
 A Dilemma is an argument, by which 
 we endeavour to prove the absurdity or 
 falsehood of some assertion. In order to 
 this, we assume a conditional proposition, 
 the antecedent of which is the assertion to 
 be disproved, and the consequent a disjunc- 
 tive proposition, enumerating all the possi- 
 ble suppositions upon which that assertion 
 can take place. If then it appear, that all 
 these suppositions ought to be rejected, it is 
 plain that the antecedent or assertion itself 
 must be rejected also. When, therefore, 
 such a proposition is made the major of any 
 syllogism, if the minor rejects all the suppo- 
 sitions contained in the consequent, it fol- 
 lows necessarily, that the conclusion must 
 reject the antecedent; which, as has been 
 said, is the assertion to be disproved. — 
 
i27 
 
 Hence it appears, that we may define a di^ 
 lemma to be a conditional or hypothetical 
 syllogism, where the consequent of the ma- 
 jor is a disjunctive proposition, which is 
 wholly taken away or removed in the minor. 
 It follows, that a dilemma is an argument 
 in the modus tollens of conditional syllo- 
 gisms. And it is plain, that if the antece- 
 dent of the major be an affirmative proposi^ 
 tion, the conclusion will be negative ; but 
 that, if it be a negative proposition, the con- 
 clusion will be affirmative. 
 
 The following is an example. 
 
 If God did not create the world perfect 
 in its kind ; it must have proceeded^ either 
 from want of inclination^ or want of power : 
 But it could not have proceeded^ either 
 from want of inclination^ or want of power : 
 Therefore it is absurb to say, that God 
 did not create the world perfect in its kin^. 
 
128 
 
 A dilemma may be faulty three ways, 
 1. When what is affirmed or denied, in the 
 minor, concerning the several suppositions 
 in the consequent of the major, is false. 2. 
 When all the possible suppositions upon 
 which the assertion, contained in the ante- 
 cedent, can take place, are not fully enu- 
 merated in the consequent. 3. When the 
 argument may be retorted with equal force 
 against him who uses it.^ 
 
 ^ There was, says Dr. Watts, a famous an- 
 cient instance of this case, w herein a dilemma was 
 retorted. Euathlus promised Protagoras a re- 
 ward when he had taught him the art of pleading;, 
 and it was to be paid the first day that he gained 
 any cause in the coui't. After a considerable 
 time, Protagoras goes to law with Euathlus for 
 the reward, and uses this dilemma. Either the 
 cause will go on my side, or on yours : if the cause 
 goes on my side^ you must pay me according to the 
 
129 
 
 A Prosy llogism is a form of reasoning, 
 in which two or more syllogisms are so 
 connected together, that the conclusion of 
 the former is the major or minor of tlie fol- 
 lowing. 
 
 Blood cannot think : 
 
 But the soul of man thinks : 
 
 Therefore the soul of man is not blood : 
 
 sentence of the judge : if the cause goes on your side, 
 you must pay me according to bargain : tlierefore 
 whether the cause goes for me^ or against me, you 
 must pay me the reward. But Eiiathlus retorted 
 this dilemma, thus. Either 1 shall gain the cause, 
 or lose it: if I gain the cause^ then nothing will be 
 due to you according to the sentence oj the judge : 
 and if Hose the cause, nothing -zvill be due to you, 
 according to my bargain: therefore, whether I lose 
 or gain the cause I will not pay you : for nothing 
 will be due to you. 
 
 WattsVs Lodck, part III. c. ii. s. 6. 
 M 3 
 
130 
 
 The soul of a brute is blood : 
 Tlierefore the soul of man is different 
 from the soul of a brute. 
 
 A Sorites is a way of arguing, in which 
 several propositions are so linked together 
 that the predicate of one becomes continual- 
 ly the subject of the next following : until 
 at last a conclusion is formed, by bringing 
 together the subject of the first proposition, 
 and the predicate of the last ; as in the follow- 
 ing example.^ 
 
 There can be no enjoyment of pro'perty^ 
 without government : 
 
 J^o government^ without a magistrate : 
 tTVb magistrate, without obedience : 
 
 ^ Themistocles, it is said, was sometimes 
 wont to use this form of reasoning, when, in the 
 way of pleasantry, he was disposed to speak of, 
 
131 
 
 Jlnd no obedience^ where every one acts as 
 he pleases : 
 
 Therefore^ there can be no enjoyment of 
 property where every one acts as he 
 pleases. 
 
 Reasoning by Induction, is when we 
 infer universally concerning any idea, what 
 we have before affirmed or denied, sepa- 
 rately, of all its several parts or subdivi- 
 sions. Thus, if we suppose the whole race 
 
 and exaggerate the influence of his son, who was 
 then a child : 
 
 My son governs his mother : 
 
 His mother governs me : 
 
 I govern Mhens : 
 
 Athens governs Greece : 
 
 Greece governs the world : 
 
 Therefore my son governs the world. 
 
13^ 
 
 of animals subdivided into men, beasts, 
 birds, insects, and fishes, and then reason 
 concerning them in this manner — All men 
 have the power of beginning motion ; all 
 leasts have this power ; all birds ; all in- 
 sects ; all fishes : therefore all animals have 
 the power of beginning motion — the argu- 
 ment is an Induction. The truth of the 
 conclusion, in this way of reasoning, de- 
 pends upon the parts and subdivisions being 
 4ully enumerated. 
 
 To this cbapier, which treats of various 
 kinds of ^^llogisms, it may not be improper 
 to add some account of several sorts of ar- 
 guments, which are usually distinguished hy 
 Latin names. For as these names will oc- 
 cajbioually occur in books and in conveisa- 
 
133 
 
 tioo, it will be of use to understand what is 
 meant by them. 
 
 Demonstrations A priori are those which 
 prove the effect from the cause : as, The 
 scripture is infallible ; because it is the 
 word of Godf who cannot lie. Demonstra- 
 tions A POSTERIORI^ on the contrary^ are those 
 which prove the cause from the effect : as, 
 till the works of God ars useful and well 
 contrived: therefore the Creator is wise 
 and good. 
 
 The ARGUMENTUM DUCENS IN ABSUR- 
 
 DUM has been already explained. We 
 shall only add, that it is sometimes called 
 REDUCTio AD ABSURDUM, and a proof PER 
 
 IMPOSSIBILE. 
 
 When we infer, that a certain proposi- 
 tion is true, because another has been prov- 
 ed to be true, which is less probable, this is 
 
134 
 
 called au argument ex minus probabili 
 
 AD MAGIS. 
 
 Wlien we argue from the certainty of a 
 thing in the same circumstances, we are 
 said to argue ex pari. 
 
 When we prove the truth of any propo- 
 sition upon whicli, if proved, our opponent 
 had agreed to admit th6 truth of the propo- 
 sition in question, this is an argument ex 
 
 CONCESSO. 
 
 When an argument is taken from the 
 nature of things and addressed to the reason 
 of mankind, it is called argumentum ad 
 
 JUDICIUM. 
 
 When it is borrowed from some con- 
 vincing testimony, it is argumentum ad fi 
 
 DEM. 
 
135 
 
 When it is drawn from any insufficient 
 meflium whatsoever, in confidence that our 
 opponent has not skill to refute or answer it^ 
 
 this is ARGUMENTUM AD XGNORANTIAM. 
 
 When we prove a thing to be true, or 
 false, from the professed opinion of the per- 
 son with whom we dispute, it is named 
 
 ARGUMENTUM AD HOMlNfcM. 
 
 When the argument is brought from the 
 sentiments of some wise, grave, or good 
 men, whose authority we reverence and 
 hardly dare oppose, it is called argumen- 
 
 TUM AD VERECUNDIAM, Or AD MODESTIAM. 
 
 When we expose a man to hatred by al- 
 leging that his opinion has been held by 
 some heretics or wicked men, calling him 
 a Socinian, a Jacobin, or the like, it is ar- 
 
 GUMEMTUM AB INVIDIA DEDUCTUM. 
 
136 
 
 And, lastly, when an argument is bor- 
 rowed from any topics, which are suited 
 to engage the inclinations or passions of the 
 hearers on the side of the speaker, rather 
 than to convince their judgments, this is 
 ARGUMENTUM AD PASSioNES, or, if it be made 
 
 publicly AD POPULUM. 
 
137 
 
 CHAPTER IlL 
 
 Of Sophisms. 
 
 Sophisms are false arguments, which 
 have the appearance of being true. 
 
 The most remarkable of them are reduced 
 by Logicians to the following heads. 
 
 1. Ignorantia elenchi^ or a mistake 
 of the question. As if, the question being 
 put, whether excess of wine he hurtful to 
 those who indulge in it, any one should ar- 
 gue, that wine revives the spirits^ gives a 
 man courage, and makes him more strong 
 and active; and then take it for granted, 
 
 that the point in debate is fully determined. 
 
 N 
 
138 
 
 But what;, it might be answered^ is all this 
 to the purpose ? Wine, taken in moderation 
 may have all these good effects which you 
 ascribe to it; but the question is not, what 
 are the effects of wine taken in moderation, 
 but what are the effects of it when taken to 
 excess. 
 
 S. Petitio principii, or a supposition 
 of what is not granted ; as^ 
 
 There is no salvation out of the church: 
 Protestants are out of the church : 
 Therefore^ Protestants cannot he saved. 
 
 The minor is here taken for granted, 
 which is by no means to be allowed. 
 
 3. A CIRCLE is, when we prove one of 
 the premises by the conclusion. 
 
 As if one were to reason thus : 
 
139 
 
 The church being infallible^ what she 
 testijies must be believed : 
 
 But the church testifies^ that the scrip- 
 tures are the word of God : 
 
 Therefore ythat the scriptures are the word 
 of God J must be believed. 
 
 — and, on being asked how it appears that 
 the church is infallible^ should undertake to 
 prove it;, as follows : 
 
 The scriptures being the word of God^ 
 what they teach must be believed : 
 
 But the scriptures teach us^ that the 
 church is infallible : 
 
 Therefore that the church is infallible^ 
 must be believed. 
 
 In this way we might prove any thing. 
 
 4. NoN CAUSA PRO CAUSA, or the assig. 
 nation of a false canse : as if any one, when 
 
140 
 
 an infectious disease is imported into a city, 
 should impute tlie misfortune to the anger of 
 God. 
 
 5. Fallacia accidentis ; when we ar- 
 gue from what is true by accident, to what 
 is true in the nature of things. So if opium, 
 or the Peruvian bark, has been used impru- 
 dently, or unsuccessfully, so as to do injury ; 
 some absolutely pronounce against the use 
 of the bark, or of opium, on all occasions, 
 and are ready to call them poisons. 
 
 6. The next sophism borders on the 
 former; and is, when we argue from that 
 which is true in particular circumstances, to 
 prove the same thing true simply, that is, 
 abstractedly from all circumstances: this is 
 called, in tlie schools, a sophism a dicto 
 
 SECUNDUM QUID, AD DICTUM SIMPLICITER J 
 
 as, 
 
141 
 
 That which is bought in the shambles is 
 eaten for dinner : 
 
 Maw meat is bought in the shambles ; 
 Therefore raw meat is eaten for dinner. 
 
 This sort of sophism has its reverse, 
 when we argue a dicto simpliciter ad 
 DICTUM SECUNDUM QUID ; 01% to express it in 
 English, from that which is true simply, or 
 abstractedly from particular circumstances, 
 to prove the same thing true when attended 
 with such circumstances: as if a traitor 
 should ar-ue from the sixth commandmentj 
 Thou shalt not kill^ to prove that he himself 
 ought not to be hanged. 
 
 7. There are also sophisms of composi- 
 tion and DIVISION. 
 
 A sophism of composition is, when we 
 infer any thing concerning ideas in a com» 
 
 N3 
 
14^ 
 
 pounded sense^ which is only true in a divi^ 
 ded sense ; aS; 
 
 Two and three are even and odd ; 
 Five are two and three ; 
 Therefore jive is even and odd. 
 
 A sophism of division is, when we infer 
 the same thing concerning ideas in a divided 
 sense, which is only true in a compound 
 sense. As^ 
 
 Five is one number ; 
 Two and three are five ; 
 Therefore two and three are one num- 
 her. 
 
 Lastly, sophisms arise also from the am- 
 biguity of words ; and indeed several of the 
 former fallacies might be reduced to this 
 head. As if one should argue thus^^ 
 
143 
 
 Jl church is a building of stone; 
 Jl religious asufembly is a church ; 
 Therefore a religious assembly is a build- 
 ing of stone. 
 
il4 
 
 Besides the special description of true 
 syllo2;isms and sophisms already given, and 
 the rules by which the one are formed and 
 the other refused ; there are these two gene- 
 ral methods of reducing all syllogisms what- 
 ever to a te&t of their truth or falsehood. 
 
 1. One of the premises must contain the 
 conclusion^ and the other must show that 
 the conclusion is contained in it. 
 
 For the illustration of this, let us take 
 the foUowing example : 
 
 Whosoever is a slave to his natural in- 
 clinations is miserable; 
 
145 
 
 A wicked man is a slave to his natural 
 inclinations ; 
 
 Therefore a wicked man is miserable. 
 
 Here it is evident, that the major propo- 
 position contains the conclusion ; for under 
 the general character of a slave to natural 
 inclinations^ a wicked man is contained or 
 included; and the minor proposition de- 
 Clares it : whence a conclusion is evidently 
 deduced that the wicked man is miserable. 
 
 3. As the terms in every syllogism are 
 usually repeated twice, so they must ^e 
 taken precisely in the same sense in both 
 places. 
 
 For the greater part of the mistakes, 
 which arise in forming sylloi^isms, is deriv- 
 ed from some little difference in the sense of 
 one of the terms in the two parts of the syh 
 logism wherein it is used. 
 
146 
 
 It is a sin to Mil a man ; 
 
 Jl murderer is a man ; 
 
 Therefore it is a sin to kill a murderer. 
 
 Here the word kill in the first proposi- 
 tion signifies to kill unjustly^ or without 
 law ; in the conclusion^ it is taken absolute- 
 ly for putting a man to death in general; and 
 therefore the inference is not good. 
 
 What I am is a man ; 
 Ton are not what I am ; 
 Therefore you are not a man. 
 
 Here, what I am^ in the major proposi- 
 tion^ U takin specially^ for my nature ; but, 
 in the minor proposition, the same words 
 are taken individually, for my person : 
 therefore the inference must he false ; for the 
 syllogism does not take the term what I am 
 both times in the same sense. 
 
147 
 
 He who says you are an animal^ says 
 true : 
 
 But he who says you are a goose^ says^ 
 you are an animal : 
 
 Therefore he^ who says^ you are a goose 
 says true. 
 
 Iq the major proposition the word ani- 
 mal is the predicate of an incidental propo- 
 sition ; which incidental proposition being 
 afBrmative^ renders the predicate of it parti- 
 cular, according to the third axiom. And 
 consequently the word animal there, signi- 
 fies only human animality. In the minor 
 proposition the word animal for the same 
 reason signifies the animality of a goose; 
 therefore it becomes an ambiguous term^ 
 and unfit to build a conclusion upon. 
 
148 
 
 PART IV, 
 
 Of Method. 
 
 We have now done with the three first 
 operations of the mind. There is yet a 
 fourth, which regards the disposal and ar- 
 rangement of our thoughts in such a manner 
 as that their mutual connexion and depen- 
 dence may be clearly seen ; and this is what 
 logicians call method. 
 
 In unfolding any part of human know- 
 ledge, the relations of things do not always 
 immediately appear, upon romparing them 
 with one another. Hence we jiave recourse 
 to intermediate ideas, and hy means of them 
 are furnished with those previous proposi- 
 
149 
 
 tions that lead to the conclusion we are in 
 quest of. And if it so happen, that the pre- 
 vious propositions themselves are not suffi« 
 ciently evident, we endeavour by new mid- 
 die terms to ascertain their truth ; still tra- 
 cing things backward, in a continued series, 
 until at length we arrive at some syllogism 
 where the premises are first and self-evident 
 principles. This done, we become perfect- 
 ly satisfied as to the truth of all the conclu- 
 sions we have passed through, inasmuch as 
 they are now seen to stand upon the firm 
 and immoveable foundation of our intuitive 
 perceptions. And as we arrived at this cer- 
 tainty by tracing our conclusions backward 
 to the original principles from which they 
 are deduced ; so we may at any time renew 
 it by a direct contrary process, if, beginning 
 with these principles, we carry the train of 
 our thoughts forward, until they lead us, by 
 a connected chain of proofs, to the very last 
 
 conclusion of the series. 
 
 O 
 
ISO 
 
 Hence it appears, that, in disposing and 
 putting together our thoughts (either for our 
 own use, — that the discoveries which we 
 have made may at all times be open to the 
 review of our minds ; or for the communi- 
 cating or unfolding of these discoveries to 
 others,) there are two ways of proceeding, 
 equally within our choice. For we may so 
 propose the truths relating to any part of 
 knowledge, as they presented themselves to 
 the mind in the manner of investigation ; 
 carrying on the series of proofs in a reverse 
 order, until they at last terminate in first 
 principles : or beginning with these princi- 
 pies, we may take the contrary way ; and 
 from them deduce, by a direct train of rea- 
 soning, all the several propositions we want 
 to establish. This diversity, in the manner 
 of arranging our thoughts, gives rise to the 
 two-fold division of method established by 
 logicians. For method, according to their 
 use of the word, is nothing else than the or- 
 
151 
 
 der and disposition of our thoughts relating 
 to any subject. When truths are so dispos. 
 ed and put together, as they were or mi^^ht 
 have been discovered, this is called the 
 
 ANALYTICK METHOD, Or the METHOD OF 
 
 RESOLUTION ; inasniuch as it traces things 
 backward to their source, and resolves 
 knowledge into its first and original princi- 
 ples. When, on the other hand, truths are 
 deduced from these first principles, and con- 
 nected according to their mutual dependence* 
 so that the truths first in order tend always 
 to the demonstration of those uhicli follow, 
 this constitutes what we call the synthetick 
 
 METHOD or METHOD OF COMPOSITION. The 
 
 first of these has also obtained the name of 
 the METHOD OF INVENTION ; becausc it ob- 
 serves the order in which our thoughts sue 
 ceed one another in the invention or disco- 
 very of truth : the , other again is often de- 
 nominated the method of science ; inas- 
 
152 
 
 much as, in laying our thoughts before 
 others, we generally choose to proceed iu 
 the synthetick manner, deducing them from 
 their first principles. 
 
 THE END, 
 
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