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been added, the confideration of a mixed fpecies concerning chances. So much for the various fubjects of difcourfe, and the forts of eviction of which they are refpectively fufceptible. This, though peculiarly the logician's province, is the foundation of all conviction, and confequently of perfuafion too. To attain either of these ends, the fpeaker muft always affume the character of the clofe and candid reafoner: for though he may be an acute logician who is no orator, he will never be a confummate orator who is no lógician.

CHAP. VI.

Of the nature and use of the fcholaftic art of fyllogizing.

HAVING in the preceding chapter endea

voured to trace the outlines of natural logic,

perhaps with more minuteness than in fuch an inquiry as this was ftrictly neceffary, it might appear ftrange to pass over in filence 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 fo long regarded, as teaching the only legitimate

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

Ir is long fince I was first convinced, by what Mr. Locke hath said on the subject, that the syllogistic art, with its figures and moods, ferves more to display the ingenuity of the inventor, and to exercise the addrefs and fluency of the learner, than to affift the diligent inquirer in his researches after truth. The method of proving by fyllogifm, appears, even on a fuperficial review, both unnatural and prolix. The rules laid down for distinguishing the conclufive from the inconclufive forms of argument, the true fyllogifm from the various kinds of fophifm, are at once cumbersome to the memory, and unneceffary in practice. No perfon, one may venture to pronounce, will ever be made a reasoner, who ftands in need of them. In a word, the whole bears the manifeft indications of an artificial and oftentatious parade of learning, calculated for giving the appearance of great profundity, to what in fact is very fhallow. Such, I acknow

ledge, have been, of a long time, my fentiments

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on the subject. On a nearer inspection, I cannot say I have found reason to alter them, though I think I have feen a little further into the nature of this difputative fcience, and confequently into the grounds of its futility. I fhall, therefore, as briefly as poffible, lay before the reader a few obfervations on the fubject, and so dismiss this article.

PERMIT me only to premife in general, that I proceed all along on the fuppofition, that the reader hath fome previous acquaintance with fchool logic. It would be extremely fuperfluous in a work like this, to give even the shortest abridgment, that could be made of an art fo well known, and which is ftill to be found in many thousand volumes. On the other hand, it is not neceffary that he be an adept in it, a mere fmattering will fufficiently ferve the present purpose.

My firft obfervation is, that this method of arguing has not the leaft affinity to moral reafoning, the procedure in the one being the very reverfe of that employed in the other. In moral reasoning we proceed by analy fis, and ascend from particulars to univerfals; in fyllogizing we proceed by fynthefis, and defcend from univerfals

to particulars. The analytic is the only method which we can follow, in the acquifition of natu→ ral knowledge, or of whatever regards actual existences; the fynthetic is more properly the method that ought to be purfued in the application of knowledge already acquired. It is for this reafon it has been called the didactic method, as being the shortest way of communicating the principles of a fcience. But even in teaching, as often as we attempt, not barely to inform, but to convince, there is a neceffity of recurring to the tract, in which the knowledge we would convey, was first attained. Now, the method of reafoning by fyllogifm, more refembles mathematical demonftration, wherein, from univerfal principles, called axioms, we deduce many truths, which, though general in their nature, may, when compared with thofe firft principles, be juftly styled particular. Whereas, in all kinds of knowledge, wherein experience is our only guide, we can proceed to general truths, folely by an induction of particulars,

AGREEABLY to this remark, if a fyllogifm be regular in mood and figure, and if the premises be true, the conclufion is infallible. The whole foundation of the fyllogiftic art lies in thefe two

axioms:

axioms:

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Things which coincide with the fame

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thing, coincide with one another;' and Two

things, whereof one does, and one does not * coincide with the fame thing, do not coincide with one another.' On the former reft all the affirmative fyllogifms, 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 fyllogifm, and make an effential part of the conclufion, and so it may also in an arithmetical computation; but this does not in the leaft affect what was advanced just now; for, in all such cases, the probability itself is affumed in one of the premifes: whereas, in the inductive method of reafoning, it often happens, that from certain facts we can deduce only probable confequences.

I OBSERVE fecondly, 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 satisfied that mathematical demonftration is capable of being

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