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been added, the confideration of a mixed fpecies concerning chances. So much for the various subjects of discourse, and the forts of eviction of which they are respectively fufceptible. This, though peculiarly the logician's province, is the foundation of all conviction, and consequently of perfuafion too. To attain either of these ends, the speaker must always afsume the character of the close and candid reasoner : for though he' may be an acute logician who is no orator, he will never be a confummate orator who is no lógician.

| C H A P. VI. Of the nature and use of the scholastic art of

Syllogizing.

H AVING in the preceding chapter endea

voured to trace the outlines of natural logic, perhaps with more minuteness than in such an inquiry as this was ftrictly necessary, it might appear strange to pass over in silence the dialectic of the schools; an art which, though now fallen into difrepute, maintained for a tract of ages, the highest reputation among the learned. What was so long regarded, as teaching the only legi

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timate use and application of our rational powers in the acquifition of knowledge, ought not surely, when we are employed in investigating the nature and the different forts of evidence, to be altogether overlooked.

It is long since I was first convinced, by what Mr. Locke hath said on the subject, that the syllogistic art, with its figures and moods, serves more to display the ingenuity of the inventor, and to exercise the address and fluency of the learner, than to assist the diligent inquirer in his researches after truth. The method of proving by fyllogism, appears, even on a superficial review, both unnatural and prolix. The rules laid down for distinguishing the conclusive from the inconclusive forms of argument, the true fyllogifm from the various kinds of sophism, are at once cumbersome to the memory, and unnecefsary in practice. No person, one may venture to pronounce, will ever be made a reasoner, who stands in need of them. In a word, the whole bears the manifeft indications of an artificial and ostentations parade of learning, calculated for giving the appearance of great profundity, to what in fact is very shallow. Such, I acknowledge, have been, of a long time, my sentiments

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on the subject. On a nearer inspection, I cannot fay I have found reason to alter them, though I think I have seen a little further into the nature of this disputative science, and consequently into the grounds of its futility. I Thall, therefore, as briefly as possible, lay before the reader a few observations on the subject, and so disiniss this article.

Permit me only to premise in general, that I proceed all along on the supposition, that the reader hath fome previous acquaintance with school logic. It would be extremely superfluous in a work like this, to give even the shortest abridgment that could be made of an art so well known, and which is still to be found in many thousand volumes. On the other hand, it is not necessary that he be an adept in it, a mere smattering will sufficiently serve the present purpose.

My first observation is, that this method of arguing has not the least affinity to moral reasoning, the procedure in the one being the very reverse of that employed in the other. In moral reasoning we proceed by analysis, and ascend from particulars to universals; in fyllogizing we proceed by fynthesis, and descend from universals to particulars. The analytic is the only method which we can follow, in the acquisition of natural knowledge, or of whatever regards actual existences; the synthetic is more properly the method that ought to be pursued in the application of knowledge already acquired. It is for this reason it has been called the didactic method, as being the shortest way of communicating the principles of a science. But even in teaching, as often as we attempt, not barely to inform, but to convince, there is a necessity of recurring to the tract, in which the knowledge we would convey, was first attained. Now, the method of reasoning by syllogism, more resembles mathematical demonstration, wherein, from universal principles, called axioms, we deduce many truths, which, though general in their nature, may, when compared with those first principles, be justly styled particular. Whereas, in all kinds of knowledge, wherein experience is our only guide, we can proceed to general truths, solely by an induction of particulars,

AGREEABLY to this remark, if a syllogism be regular in mood and figure, and if the premises be true, the conclusion is infallible. The whole foundation of the fyllogistic art lies in these two

axioms : axioms : “ Things which coincide with the fame • thing, coincide with one another;' and · Two • things, whereof one does, and one does not • coincide with the same thing, do not coincide • with one another.' On the former rest all the affirmative fyllogifins, on the latter all the negative. Accordingly, there is no more mention here of probability and of degrees of evidence, than in the operations of geometry' and algebra. It is true, indeed, that the term probable may be admitted into a fyllogism, and make an essential part of the conclusion, and so it may also in an arithmetical computation ; but this does not in the least affect what was advanced juit now; for, in all such cases, the probability itself is assumed in one of the premises : whereas, in the induc- .' tive method of reasoning, it often happens, that from certain facts we can deduce only probable consequences.

I OBSERV e secondly, that though this manner of arguing has more of the nature of scientific reasoning, than of moral, it has, nevertheless, not been thought worthy of being adopted by mathematicians, as a proper method of demonftrating their theorems. I am fatisfied that mathematical demonftration is capable of being M 4

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