tions many others that are lost. Those I have mentioned have commonly been published together, under the name, Aristotle's Organon, or his Logic; and for many ages, Porphyry's Introduction to the Categories has been prefixed to them.

SECTION II.

OF PORPHYRY'S INTRODUCTION.

In this Introduction, which is addressed to Chrysoarius, the author observes, that in order to understand Aristotle's doctrine concerning the categories, it is necessary to know what a genus is, what a species, what specific difference, what a property, and what an accident; that the knowledge of these is also very useful in definition, in division, and even in demonstration: therefore he proposes, in this little tract, to deliver shortly and * simply the doctrines of the ancients, and chiefly of the Peripatetics, concerning these five predicables; avoiding the more intricate questions concerning them; such as, whether genera and species do really exist in nature? or, whether they are only conceptions of the human mind? If they exist in nature, whether they are corporeal or incorporeal? and whether they are inherent in the objects of sense, or disjointed from them? These, he says, are very difficult questions, and require accurate discussion; but that he is not to meddle with them.

After this preface, he explains very minutely each of the five words above mentioned, divides and subdivides each of them, and then pursues all the agreements and differences between one and another through sixteen chapters.

SECTION III.

OF THE CATEGORIES.

THE book begins with an explication of what is meant by univocal words, what by equivocal, and what by denominative. Then it is observed, that what we say is either simple, without composition or structure, as man, horse; or it has composition and structure, as a man fights, the horse runs. Next comes a distinction between a subject of predication; that is, a subject of which any thing is affirmed or denied, and a subject of inhesion. These things are said to be inherent in a subject, which, although they are not part of a subject, cannot possibly exist without it, as figure in the thing figured. Of things that are,

says Aristotle, some may be predicated of a subject, but are in no subject; as man may be predicated of James or John, but it is not in any subject. Some again are in a subject, but can be predicated of no subject. Thus, my knowledge in grammar is in me as its subject, but it can be predicated of no subject; because it is an individual thing. Some are both in a subject, and may be predicated of a subject, as science; which is in the mind as its subject, and may be predicated of geometry. Lastly, some things can neither be in a subject, nor be predicated of any subject. Such are all individual substances, which cannot be predicated, because they are individuals; and cannot be in a subject, because they are substances. After some other subtilties about predicates and subjects, we come to the categories themselves; the things above mentioned being called by the schoolmen the anteprædicamenta. It may be observed, however, that notwithstanding the distinction now explained, the being in a subject, and the being predicated truly of a subject, are in the Analytics used as synonymous phrases; and this variation of style has led some persons to think that the Categories were not written by Aristotle.

Things which may be expressed without composition or structure, are, says the author, reducible to the following heads. They are either substance or quantity, or quality, or relatives, or place, or time, or having, or doing, or suffering. These are the predicaments or categories. The first four are largely treated of in four chapters; the others are slightly passed over, as sufficiently clear of themselves. As a specimen, I shall give a summary of what he says on the category of substance.

Substances are either primary, to wit, individual substances, or secondary, to wit, the genera and species of substances. Primary substances neither are in a subject, nor can be predicated of a subject; but all other things that exist, either in primary substances, or may be predicated of them. For whatever can be predicated of that which is in a subject, may also be predicated of the subject itself. Primary substances are more substances than the secondary; and of the secondary, the species is more a substance than the genus. If there were no primary, there could be no secondary substances.

The properties of substance are these: 1. No substance is capable of intention or remission. 2. No substance can be in any other thing as its subject of inhesion. 3. No substance has a contrary; for one substance cannot be contrary to another; nor can there be contrariety between a substance, and that which is no substance. 4. The most remarkable property of substance, is, that one and the same substance may, by some change in itself, become the subject of things that are contrary. Thus, the same body may be at one time hot, at another cold.

Let this serve as a specimen of Aristotle's manner of treating the categories. After them, we have some chapters, which the schoolmen call postprædicamenta; wherein, first, the four kinds of opposition of terms are explained; to wit, relative, privative, of contrariety, and of contradiction. This is repeated of all systems of logic. Last of all we have distinctions of the four Greek words which answer to the Latin ones, prius, simul, motus, and habere.

SECTION IV.

OF THE BOOK CONCERNING INTERPRETATION.

WE are to consider, says Aristotle, what a noun is, what a verb, what affirmation, what negation, what speech. Words are the signs of what passeth in the mind; writing is the sign of words. The signs both of writing and of words are different in different nations, but the operations of mind signified by them are the same. There are some operations of thought which are neither true nor false. These are expressed by nouns or verbs singly, and without composition.

A noun is a sound which by compact signifies something without respect to time, and of which no part has signification by itself. The cries of beasts may have a natural signification, but they are not nouns. We give that name only to sounds which have their signification by compact. The cases of a noun, as the genitive, dative, are not nouns. Non homo is not a noun, but, for distinction's sake, may be called a nomen infinitum.

A verb signifies something by compact with relation to time. Thus, valet is a verb; but valetudo is a noun, because its signification has no relation to time. It is only the present tense of the indicative that is properly called a verb; the other tenses and moods are variations of the verb. Non valet may be called a

verbum infinitum.

Every

Speech is sound significant by compact, of which some part is also significant. And it is either enunciative, or not enunciative. Enunciative speech is that which affirms or denies. As to speech which is not enunciative, such as a prayer or wish, the consideration of it belongs to oratory or poetry. enunciative speech must have a verb, or some 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 opposite. This is a summary of the first six chapters.

The seventh and eighth treat of the various kinds of enunciations or propositions, universal, particular, indefinite, and singu

lar; and of the various kinds of opposition in propositions, and the axioms concerning them. These things are repeated in every system of logic. In the ninth chapter he endeavours to prove, by a long metaphysical reasoning, that propositions respecting future contingencies are not, determinately, either true or false; and that if they were, it would follow, that all things happen necessarily, and could not have been otherwise than they are. The remaining chapters contain many minute observations concerning the equipollency of propositions both pure and modal.

CHAPTER II.

REMARKS.

SECTION I.

OF THE FIVE PREDICABLES.

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

The three treatises of which we have given a brief account, are unconnected with each other, and with those that follow. And although the first was undoubtedly compiled by Porphyry, and the two last probably by Aristotle, yet I consider them as the venerable remains of a philosophy more ancient than Aristotle. Archytas of Tarentum, an eminent mathematician and philosopher of the Pythagorean school, is said to have written upon the ten categories. And the five predicables probably had their origin in the same school. Aristotle, though abundantly careful to do justice to himself, does not claim the invention of either. And Porphyry, without ascribing the latter to Aristotle, professes 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 simple apprehension, and of terms; the second, of judgment, and of propositions; and the third, of reasoning, and of syllogisms. The materials of the first part are taken from Porphyry's Introduction, and the Categories: and those of the second from the book of Interpretation.

A predicable, according to the grammatical form of the word, might seem to signify, whatever may be predicated, that is, affirmed or denied, of some subject. And in this sense every predicate would be a predicable. But the logicians give a different meaning to the word. They divide propositions into certain classes, according to the relation which the predicate of the proposition bears to the subject. The first class is that wherein the predicate is the genus of the subject; as when we say, this is a triangle, Jupiter is a planet. In the second class, the predicate is a species of the subject; as when we say, this triangle is right-angled. A third class is when the predicate is the specific difference of the subject; as when we say, every triangle has three sides and three angles. A fourth when the predicate is the property of the subject; as when we say, the angles of every triangle are equal to two right angles. And a fifth class is when the predicate is something accidental to the subject; as when we say, this triangle is neatly drawn.

Each of these classes comprehends a great variety of propositions having different subjects, and different predicates; but in each class the relation between the predicate and the subject is the same. 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 propositions between the predicate and the subject. And if all propositions belong to one or other of the five classes above mentioned, there can be but five predicables, to wit, genus, species, differentia, proprium, and accidens. These might, with more propriety perhaps, have been called the five classes of predicates; but use has determined them to be called the five predicables.

It may also be observed, that as some objects of thought are individuals, such as, Julius Cæsar, the city Rome ; so others are common to many individuals, as, good, great, virtuous, vicious. Of this last kind are all things expressed by adjectives. Things common to many individuals were by the ancients called universals. All predicates are universals, for they all have the nature of adjectives; and, on the other hand, all universals may be predicates. On this account universals may be divided into the same classes as predicates, and as the five classes of predicates above mentioned have been called the five predicables, so by the same kind of phraseology they have been called the five universals; although they may more properly be called the five classes of universals.

The doctrine of the five universals or predicables makes an essential part of every system of logic, and has been handed down without any change to this day. The very name of