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ported by the premises, the conclufion, in that cafe, will always be found different from that which ought to have been proved; and fo it falls under the ignoratio elenchi.

It was probably Ariftotle's aim, to reduce all the poffible variety of fophifms, as he had attempted to do of juft fyllogifms, to certain definite fpecies: but he feems to be fenfible that he had fallen fhort in this laft attempt. When a genus is properly divided into its fpecies, the fpecies fhould not only, when taken together, exhauft the whole genus; but every fpecies should have its own precinct fo accurately defined, that one fhall not encroach upon another. And when an individual can be faid to belong to two or three different fpecies, the divifion is imperfect; yet this is the cafe of Ariftotle's divifion of the fophifms, by his own acknowledgement. It ought not therefore to be taken for a divifion ftrictly logical. It may rather be compared to the several fpecies or forms of action invented in law for the redrefs of wrongs. For every wrong there is a remedy in law by one action or another: but fometimes a man

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may take his choice among feveral different actions. So every fophiftical fyllogifm may, by a little art, be brought under one or other of the fpecies mentioned by Aristotle, and very often you may take your

choice of two or three.

Befides the enumeration of the various kinds of fophifms, there are many other things in this treatife concerning the art of managing a fyllogiftical difpute with an antagonist. And indeed, if the paffion for this kind of litigation, which reigned for so many ages, fhould ever again lift up its head, we may predict, that the Organon of Ariftotle will then become a fafhionable study: for it contains fuch admirable materials and documents for this art, that it may be faid to have brought it to a science.

The conclufion of this treatise ought not to be overlooked: it manifeftly relates, not to the present treatise only, but also to the whole analytics and topics of the author. I fhall therefore give the substance of it.

"Of those who may be called inventers, "fome have made important additions to things long before begun, and carried VOL. III.

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on through a course of ages; others "have given a small beginning to things "which, in fucceeding times, will be

brought to greater perfection. The be"ginning of a thing, though small, is the "chief part of it, and requires the great"eft degree of invention; for it is easy

to make additions to inventions once "begun. Now with regard to the dia"lectical art, there was not fomething "done, and fomething remaining to be ❝ done. There was abfolutely nothing "done: for those who profeffed the art "of difputation, had only a set of ora"tions compofed, and of arguments, and "of captious queftions, which might fuit

many occafions. These their scholars "foon learned, and fitted to the occafion. "This was not to teach you the art, but

to furnish you with the materials pro"duced by the art: as if a man profef

fing to teach you the art of making "fhoes, fhould bring you a parcel of "fhoes of various fizes and fhapes, from "which you may provide thofe who want. "This may have its ufe; but it is not to "teach the art of making fhoes. And "indeed, with regard to rhetorical declamation,

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"mation, there are many precepts handed "down from ancient times; but with regard to the construction of fyllogifms,

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"We have therefore employed much "time and labour upon this fubject; and "if our system appear to you not to be "in the number of those things, which, "being before carried a certain length,

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were left to be perfected; we hope for 66 your favourable acceptance of what is "done, and your indulgence in what is " left imperfect."

CHA P. VI.

Reflections on the Utility of Logic, and the Means of its improvement.

SECT. I. Of the Utility of Logic.

MEN rarely leave one extreme without running into the contrary. It is no wonder, therefore, that the exceffive admiration of Aristotle, which continued for

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fo many ages, fhould end in an undue contempt; and that the high esteem of logic as the grand engine of science, should at laft make way for too unfavourable an opinion, which feems now prevalent, of its being unworthy of a place in a liberal education. Those who think according to the fashion, as the greatest part of men do, will be as prone to go into this extreme, as their grandfathers were to go into the contrary.

Laying afide prejudice, whether fashionable or unfafhionable, let us confider whether logic is, or may be made, subservient to any good purpose. Its profeffed end is, to teach men to think, to judge, and to reason, with precision and accuracy. No. man will fay that this is a matter of no importance; the only thing therefore that admits of doubt, is, whether it can be taught.

To refolve this doubt, it may be observed, that our rational faculty is the gift of God, given to men in very different measure. Some have a large portion, fome a lefs; and where there is a remarkable defect of the natural power, it cannot be fupplied by any culture. But this natural

power,

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