what fpeech. Words are the figns of what paffeth in the mind; writing is the fign of words. The figns both of writing and of words are different in, different nations, but the operations of mind fignified by them are the fame. There are fome operaneither true nor falfe.

tions of thought, which are

These are expreffed by nouns or verbs fingly, and, without compofition.

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A noun is a found, which, by compact, fignifies fomething without respect to time, and of which no part has fignification by itself. The cries of beafts may have a natural fignification, but they are not nouns; we give that name only to founds which, have their fignification by compact. The cafes of a noun, as the genitive, dative, are not nouns. Non homo is not a noun, but, for diftinction's fake, may be called a nomen infinitum.

A verb fignifies fomething by compact with relation to time. Thus valet is a verb; but valetudo. is a noun, because its fignification has no relation to time. It is only the prefent tenfe of the indicative that is properly called a verb; the other tenfes; and moods are variations of the verb. Non valet may be called a verbum infinitum.

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 speech myt have a verb, or fome variation of 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 first fix chapters.

The seventh and eighth treat of the various kinds of enunciations or propofitions, universal, particular, indefinite, and fingular; and of the various kinds of oppofition in propofitions, and the axioms concerning them. These 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 false; and that if they were, it would follow, that all things happen neceffarily, and could not have been otherwise than as they are. The remaining chapters contain many minute obfervations concerning the equipollency of propofitions both pure and modal.

CHAP.

CHAP. II.

REMARKS.

SECT. I. On the Five Predicables.

HE writers on logic have borrowed their ma

THE

terials almost entirely from Ariftotle's Organon, and Porphyry's Introduction. The Organon, however, was not written by Ariftotle as one 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 fayed.

1

The three treatifes of which we have given a brief account, are unconnected with each other, and with thofe that follow. And although the first was undoubtedly compiled by Porphyry, and the two laft probably by Ariftotle, yet I confider them as the venerable remains of a philofophy more ancient than Ariftotle. Archytas of Tarentum, an eminent mathematician and philofopher

of

of the Pythagorean fchool, is faid to have wrote upon the ten categories; and the five predicables probably had their origin in the fame fchool. Ariftotle, though abundantly careful to do justice to himself, does not claim the invention of either. And Porphyry, without afcribing the latter to Ariftotle, profeffes only to deliver the doctrine of the ancients and chiefly of the Peripatetics, concerning them.

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

1

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 first class is that wherein the predicate is the genus of the subject; of the fubject; as when we fay, This is a triangle, Jupiter is a planet. In the fecond class, the predicate is a Species of the fubject; as when we fay, This triangle is right-angled. A

third clafs is when the predicate is the specific 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 these claffes comprehends a great variety of propofitions, having different fubjects, and different predicates; but in each clafs the relation between the predicate and the subject is the fame. Now it is to this relation that logicians have given the name of a predicable. Hence it is, that although 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. Thefe 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 also be observed, that as some 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 adVOL. III. jectives.

B