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After perusing the above exposition of Aristotle's demonstration, the reader, if the subject be altogether new to him, will be apt to imagine, that the study of logic is an undertaking of much less difficulty than he had been accustomed formerly to apprehend; the whole resolving ultimately into this axiom, "That if A contains B, and B contains C, then A contains C." In interpreting this axiom, he will probably figure to himself A, B, and C, as bearing some resemblance to three boxes, the sizes of which are so adapted to each other, that B may be literally put into the inside of A, and C into the inside of B. Perhaps it may be reasonably doubted, if there is one logician in a hundred, who ever dreamed of understanding it in any other sense. When considered in this light, it is not surprising that it should instantly command the assent of the merest novice: nor would he hesitate one moment longer about its truth, if, instead of being limited (in conformity to the three terms of a syllogism) to the three letters, A, B, C, it were to be extended from A to Z; the series of boxes corresponding to the series of letters, being all conceived to be nestled, one within another, like those which we sometimes see exhibited in the hands of a juggler.

If the curiosity of the student, however, should lead him to inquire a little more accurately into Aristotle's meaning, he will soon have the mortification to learn, that when one thing is said by the logician, to be in another, or to be contained in another, these words are not to be understood in their ordinary and most obvious sense, but in a particular and technical sense, known only to adepts; and about which (we may remark by the way) adepts are not, to this day, unanimously agreed. "To those," says Lord Monboddo, "who know no more of logic nor

gravity, and dignity of his unpremeditated elocution;-and yet, so completely had his faculties been subdued by the vain abstractions and verbal distinctions of the schools, that he had brought himself seriously to regard such discussions as that which I have here transcribed from his works, not only as containing much excellent sense, but as the quintessence of sound philosophy. As for the mathematical and physical discoveries of the Newtonians, he held them in comparative contempt, and was probably prevented, by this circumstance, from ever proceeding farther than the first elements of these sciences. Indeed, his ignorance of both was wonderful, considering the very liberal education which he had received, not only in his own country, but at a foreign university.

of ancient philosophy than Mr. Locke did, it will be necessary to explain in what sense one idea can be said to contain another, or the idea less general can be said to be a part of the more general. And, in the first place, it is not in the sense that one body is said to be a part of another, or the greater body to contain the lesser ; nor ́is it as one number is said to contain another; but it is virtually or potentially that the more general idea contains the less general. In this way the genus contains the species; for the genus may be predicated of every species under it, whether existing or not existing; so that virtually it contains all the specieses under it, which exist or may exist. And not only does the more general contain the less general, but (what at first sight may appear surprising) the less general contains the more general, not virtually or potentially, but actually. Thus, the genus animal contains virtually man, and every other species of animal either existing or that may exist: But the genus animal is contained in man, and in other animals actually; for man cannot exist without being in actuality, and not potentially only an animal." *

If we have recourse to Dr. Gillies for a little more light upon this question, we shall meet with a similar disappointment. According to him, the meaning of the phrases in question is to be sought for in the following definition of Aristotle: "To say that one thing is contained in another, is the same as saying, that the second can be predicated of the first in the full extent of its signification; and one term is predicated of another in the full extent of its signification, when there is no particular denoted by the subject, to which the predicate does not apply."† In

* Ancient Metaphysics, Vol. IV. p. 73.

For the distinction betwixt containing potentially and actually, Lord Monboddo acknowledges himself indebted to a Greek author then living, Eugenius Diaconus. (Anc. Met. Vol. IV. p. 73.) Of this author we are elsewhere told, that he was a Professor in the Patriarch's University at Constantinople; and that he published, in pure Attic Greek, a system of logic, at Leipsic, in the year 1766. (Origin and Progress of Language, Vol. I. p. 45, 2d edit.) It is an extraordinary circumstance, that a discovery, on which, in Lord Monboddo's opinion, the whole truth of the syllogism depends, should have been of so very recent a date.

† Gillies's Aristotle, Vol. I. p. 73. "This remark," says Dr. Gillies, "which is the foundation of all Aristotle's logic, has been sadly mistaken by many. Among others, Dr. Reid accuses Aristotle of using as synonymous phrases, the being in a subject, and the being truly predicated of a subject; whereas the truth is, that, according to Aristotle, the meaning of the one phrase is directly the reverse of the meaning of the other."-Ibid.

order, therefore, to make sure of Aristotle's idea, we must substitute the definition instead of the thing defined; that is, instead of saying that one thing is contained in another, we must say, that "the second can be predicated of the first in the full extent of its signification." In this last clause, I give Aristotle all the advantage of Dr. Gillies's very paraphrastical version; and yet, such is the effect of the comment, that it at once converts our axiom into a riddle. I do not say that, when thus interpreted, it is altogether unintelligible; but only that it no longer possesses the same sort of evidence which we ascribe to it, while we supposed that one thing was said by the logician to be contained in another, in the same sense in which a smaller box is contained in a greater.*

To both comments the same observation may be applied; that, the moment a person reads them, he must feel himself disposed to retract his assent to the axiom which they are brought to elucidate; inasmuch as they must convince him, that what appeared to be, according to the common signification of words, little better than a truism, becomes, when translated into the jargon of the schools, an incomprehensible, if not, at bottom, an unmeaning ænigma.

I have been induced to enlarge, with more minuteness than I could have wished, on this fundamental article of logic, that I might not be accused of repeating those common-place generalities which have, of late, been so much complained of by Aristotle's champion. I must not, however, enter any farther into the details

While I readily admit the justness of this criticism on Dr. Reid, I must take the liberty of adding, that I consider Reid's error as a mere oversight, or slip of the pen. That he might have accused Aristotle of confounding two things which, although different in fact, had yet a certain degree cf resemblance or affinity, is by no means impossible but it is scarcely conceivable, that he could be so careless as to accuse him of confounding two things which he invariably states in direct opposition to each other. I have not a doubt, therefore, that Reid's idea was, that Aristotle used, as synonymous phrases, the being in a thing, and the being a subject of which that thing can be truly predicated; more especially, as either statement would equally well have answered his purpose.

*It is worthy of observation, that Condillac has availed himself of the same metaphorical and equivocal word which the foregoing comments profess to explain, in support of the theory which represents every process of sound reasoning as a series of identical propositions. "L'Analyse est la même dans toutes les sciences, parce que dans toutes elle conduit du connu à l'inconnu par le raisonnement, c'est-à-dire, par une suite de jugemens qui sont renfermés les uns dans les autres.”—La Logique.

of the system; and shall therefore proceed, in the next section, to offer a few remarks of a more practical nature, on the object and on the value of the syllogistic

art.

SECTION II.

General Reflections on the Aim of the Aristotelian logic, and on the Intellectual Habits which the study of it has a tendency to form.-That the Improvement of the Power of Reasoning ought to be regarded as only a secondary Object in the culture of the Understanding.

THE remarks which were long ago made by Lord Bacon on the inutility of the syllogism as an organ of scientific discovery, together with the acute strictures in Mr. Locke's Essay on this form of reasoning, are so decisive in point of argument, and, at the same time, so familiarly known to all who turn their attention to philosophical inquiries, as to render it perfectly unnecessary for me, on the present occasion, to add any thing in support of them. I shall, therefore, in the sequel, confine myself to a few very general and miscellaneous reflections on one or two points overlooked by these eminent writers; but to which it is of essential importance to attend, in order to estimate justly the value of the Aristotelian logic, considered as a branch of educa tion.*

It is an observation which has been often repeated since Bacon's time, and which, it is astonishing, was so long in forcing itself on the notice of philosophers, That, in all our reasonings about the established order of the universe, experience is our sole guide, and knowledge is to be acquired only by ascending from particulars to generals; whereas the syllogism leads us invariably from universals to particulars, the truth of which, instead of being a consequence of the universal proposition, is implied and presupposed in the very terms of its

*To some of my readers it may not be superfluous to recommend, as a valuable supplement to the discussions of Locke and Bacon concerning the syllogistic art, what has been since written on the same subject, in farther prosecution of their views by Dr. Reid in his Analysis of Aristotle's Logic, and by Dr. Campbell in his Philos. ophy of Rhetoric.

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same truth; their only wish is, to discover the easiest and shortest road by which the truth may be reached. In point of simplicity, and of what geometers call elegance, these various demonstrations may differ widely from each other; but, in point of sound logic, they are all precisely on the same footing. Each of them shines with its own intrinsic light alone; and the first which occurs (provided they be all equally understood) commands the assent not less irresistibly than the last.

The idea, however, on which Aristotle proceeded, in attempting to fortify one demonstration by another, bears no analogy whatever to the practice of mathematicians in multiplying proofs of the same theorem; nor can it derive the slightest countenance from their example. His object was not to teach us how to demonstrate the same thing in a variety of different ways; but to demonstrate, by abstract reasoning, the conclusiveness of demonstration. By what means he set about the accomplishment of his purpose, will afterwards appear. At present, I speak only of his design; which, if the foregoing remarks be just, it will not be easy to reconcile with correct views, either concerning the nature of evidence, or the theory of the human understanding.

For the sake of those who have not previously turned their attention to Aristotle's Logic, it is necessary, before proceeding farther, to take notice of a peculiarity (and, as appears to me, an impropriety) in the use which he makes of the epithets demonstrative and dialectical, to mark the distinction between the two great classes into which he divides syllogisms; a mode of speaking which, according to the common use of language, would seem to imply, that one species of syllogisms may be more conclusive and cogent than another. That this is not the case, is almost self-evident; for, if a syllogism be perfect in form, it must, of necessity, be not only conclusive, but demonstratively conclusive. Nor is this, in fact, the idea which Aristotle himself annexed to the distinction; for he tells us, that it does not refer to the form of syllogisms, but to their matter;—or, in plainer language, to the degree of evidence accompany

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