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Speech is found fignificant by compact, of which fome part is alfo fignificant. And it is either enunciative, or not enunciative. Enunciative speech is that which affirms or denies. As to fpeech which is not enunciative, fuch as a prayer or wifh, the confideration of it belongs to oratory, or poetry. Every enunciative fpeech must have a verb. Affirmation

is the enunciation of one thing concerning another. Negation is the enunciation of one thing from another. Contradiction is an affirmation and negation that are oppofite. This is a fummary of the firit fix chapters.

The feventh and eighth treat of the various kinds of enunciations or propofitions, univerfal, particular, indefinite, and fingular, and of the various kinds of oppofition in propofitions, and the axioms concerning them. Thefe things are repeated in every fyftem of logic. In the ninth chapter he endeavours to prove by a long metaphyfical reasoning, that propofitions refpecting future contingencies are not, determinately, either true or falfe; and that if they were, it would follow, that all things happen neceffarily, and could not have been otherwife than as they are. The remaining chapters contain many minute obfervations concerning the equipollency of propofitions both pure and modal.

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II.

REMARK S.

SECT. 1. On the Five Predicables.

THE

one

HE writers on logic have borrowed their materials almost entirely from Ariftotle's Organon, and Porphyry's Introduction. The Organon however was not written by Aristotle as work. It comprehends various tracts, written without the view of making them parts of one whole, and afterwards thrown together by his editors under one name on account of their affinity. Many of his books that are loft, would have made a part of the Organon if they had been faved.

The three treatifes of which we have given a brief account, are unconnected with each other, and with thofe that follow. And although the firft was undoubtedly compiled by Porphyry and the two last probably by Ariftotle, yet I confider them as the venerable remains of a philofophy more ancient than Aristotle. Archytas of Tarentum, an eminent mathematician and philofopher of the Pythagorean fchool, is faid to have wrote upon the ten categories; and the five predicables probably had their origin in the fame school. Ariftotle, though abundantly careful to do juftice to himfelf, does not claim the invention of either. And Porphyry, without afcribing the latter to Ariftotle, profeffes only to deliver the doctrine of

the

the ancients and chiefly of the Peripatetics, concerning them.

The writers on logic have divided that science into three parts; the firft treating of fimple apprehenfion and of terms; the fecond, of judgement and of propofitions; and the third, of reafoning and of fyllogifms. The materials of the first part are taken from Porphyry's Introduction and the Categories; and thofe of the fecond from the book of Interpretation.

A predicable, according to the grammatical form of the word, might feem to fignify, whatever may be predicated, that is, affirmed or denied, of a fubject and in that fenfe every predicate would be a predicable. But logicians give a different meaning to the word. They divide propofitions into certain claffes, according to the relation which the predicate of the propofition bears to the fubject. The firft clafs is that wherein the predicate is the genus of the fubject; as when we fay, This is a triangle, Jupiter is a planet. In the fecond class, the predicate is a fpecies of the fubject; as when we fay, This triangle is right-angled. A third clafs is when the predicate is the fpecific difference of the fubject; as when we fay, Every triangle has three fides and three angles. A fourth when the predicate is a property of the fubject; as when we fay, The angles of every triangle are equal to two right angles. And a fifth clafs is when the predicate is fomething accidental to the fubject; as when we fay, This triangle is neatly drawn.

Each of thefe claffes comprehends a great variety of propofitions, having different fubjects, and different predicates; but in each clafs the relation between the predicate and the fubject is the fame. Now it is to this relation that logicians have given the name of a predicable. Hence it is,

VOL. II.

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that altho' the number of predicates be infinite, yet the number of predicables can be no greater than that of the different relations which may be in propofitions between the predicate and the fubject. And if all propofitions belong to one or other of the five claffes above-mentioned, there can be but five predicables, to wit, genus, fpecies, differentia, proprium, and accidens. These might, with more propriety perhaps have been called the five claffes of predicates; but ufe has determined them to be called the five predicables.

It may alfo be obferved, that as fome objects of thought are individuals, fuch as, Julius Cæfar, the city Rome fo others are common to many individuals, as good, great, virtuous, vicious. Of this laft kind are all the things that are expreffed by adjectives. Things common to many individuals, were by the ancients called univerfals. All predicates are univerfals, for they have the nature of adjectives; and, on the other hand, all univerfals may be predicates. On this account, univerfals may be divided into the fame claffes as predicates; and as the five claffes of predicates above-mentioned have been called the five predicables, fo by the fame kind of phrafeology they have been called the five univerfals; although they may more properly be called the five claffes of univerfals.

The doctrine of the five univerfals or predica bles makes an effential part of every fyftem of logic, and has been handed down without any change to this day. The very name of predica bles thews, that the author of this divifion, whoever he was, intended it as a complete enumeration of all the kinds of things that can be affirmed of any fubject; and fo it has always been underfood. It is accordingly implied in this divifion, that all that can be affirmed of any thing what

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ever, is either the genus of the thing, or its fpecies, or its specific difference, or some property or accident belonging to it.

Burgerfdick, a very acute writer in logic, feems. to have been aware, that strong objections might be made to the five predicables, confidered as a complete enumeration: but, unwilling to allow any imperfection in this ancient divifion, he endeavours to restrain the meaning of the word predicable, fo às to obviate objections. Thofe things only, fays he, are to be accounted predicables, which may be affirmed of many individuals, truly, properly, and immediately. The confequence of putting fuch limitations upon the word predicable is, that in many propofitions, perhaps in moft, the predicate is not a predicable. But admitting all his limitations, the enumeration will ftill be very incomplete for of many things we may affirm truly, properly, and immediately, their exiftence, their end, their caufe, their effect, and various relations which they bear to other things.

Thefe, and perhaps many more, are predicables in the ftrict fenfe of the word, no less than the five which have been fo long famous.

Although Porphyry and all fubfequent writers, make the predicables to be, in number, five; yet Ariftotle himself, in the beginning of the Topics, reduces them to four; and demonftrates, that there can be no more. We fhall give his demonstration when we come to the Topics; and fhall only here obferve, that as Burgerfdick juftifies the five-fold divifion, by reftraining the meaning of the word predicable; fo Ariftotle juftifies the fourfold divifion, by enlarging the meaning of the words property and accident.

After all, I apprehend, that this ancient divifion of predicables with all its imperfections, will bear a comparison with those which have been fubftituted

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