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apprehend this is a rich field of philosophical speculation. Language being the express image of human thought, the analysis of the one must correspond to that of the other. Nouns adjective and substantive, verbs active and passive, with their various moods, tenses, and persons, must be expressive of a like variety in the modes of thought. Things that are distinguished in all languages, such as substance and quality, action and passion, cause and effect, must be distinguished by the natural powers of the human mind. The philosophy of grammar, and that of the human understanding, are more nearly allied than is commonly imagined.

The structure of language was pursued to a considerable extent, by the ancient commentators upon this book of Aristotle. Their speculations upon this subject, which are neither the least ingenious nor the least useful part of the Peripatetic philosophy, were neglected for many ages, and lay buried in ancient manuscripts, or in books little known, till they were lately brought to light by the learned Mr Harris in his Hermes.

The definitions given by Aristotle, of a noun, of a verb, and of speech, will hardly bear examination. It is easy in practice to distinguish the various parts of speech; but very difficult, if at all possible, to give accurate definitions of them.

He observes justly, that besides that kind of. speech called a proposition, which is always either


true or false, there are other kinds which are neither true nor false; such as, a prayer, or wish; to which we may add, a question, a command, a promise, a contract, and many others. These Aristotle pronounces to have nothing to do with his subject, and remits them to oratory, or poetry; and so they have remained banished from the regions of philosophy to this day: yet I apprehend, that an analysis of such speeches, and of the operations of mind which they express, would be of real use, and perhaps would discover how imperfect an enumeration the logicians have given of the powers of human understanding, when they reduce them to simple apprehension, judgment, and reasoning.

SECT. 6. On Propositions.

Mathematicians use the word proposition in a larger sense than logicians. A problem is called a proposition in mathematics, but in logic it is not a proposition it is one of those speeches which are not enunciative, and which Aristotle remits to oratory or poetry.


- A proposition, according to Aristotle, is a speech wherein one thing is affirmed or denied of another. Hence it is easy to distinguish the thing affirmed or denied, which is called the predicate, from the thing of which it is affirmed or denied, which is called the subject; and these two are call

ed the terms of the proposition. Hence likewise it appears, that propositions are either affirmative or negative; and this is called their quality. All affirmative propositions have the same quality, so likewise have all negative; but an affirmative and a negative are contrary in their quality.

When the subject of a proposition is a general term, the predicate is affirmed or denied, either of the whole, or of a part. Hence propositions are distinguished into universal and particular. All men are mortal, is an universal proposition; Some men are learned, is a particular; and this is called the quantity of the proposition. All universal propositions agree in quantity, as also all particular: but an universal and a particular are said to differ in quantity. A proposition is called indefinite, when there is no mark either of universality or particularity annexed to the subject: thus, Man is of few days, is an indefinite proposition; but it must be understood either as universal or as particular, and therefore is not a third species, but by interpretation is brought under one of the other


There are also singular propositions, which have not a general term but an individual for their subject; as, Alexander was a great conqueror. These are considered by logicians as universal, because, the subject being indivisible, the predicate is affirmed or denied of the whole, and not of a part only. Thus all propositions, with regard to qua

lity, are either affirmative or negative; and with regard to quantity, are universal or particular; and taking in both quantity and quality, they are universal affirmatives, or universal negatives, or particular affirmatives, or particular negatives, These four kinds, after the days of Aristotle, came to be named by the names of the four first vowels, A, E, I, O, according to the following distich:

Asserit A, negat E, sed universaliter ambæ ;

Asserit I, negat O, sed particulariter ambo. When the young logician is thus far instructed in the nature of propositions, he is apt to think there is no difficulty in analysing any proposition, and shewing its subject and predicate, its quantity and quality; and indeed, unless he can do this, he will be unable to apply the rules of logic to use, Yet he will find, there are some difficulties in this analysis, which are overlooked by Aristotle altoge. ther; and although they are sometimes touched, they are not removed by his followers. For,

1. There are propositions in which it is difficult to find a subject and a predicate; as in these, It rains, It snows. 2. In some propositions either term may be made the subject or the predicate as you like best; as in this, Virtue is the road to happiness. 3. The same example may serve to shew, that it is sometimes difficult to say, whether a proposition be universal or particular. 4. The quality of some propositions is so dubious, that logicians have never been able to agree whether they be affirmative or negative;


negative; as in this proposition, Whatever is insentient is not animal. 5. As there is one class of propositions which have only two terms, to wit, one subject and one predicate, which are called categorical propositions; so there are many classes that have more than two terms. What Aristotle delivers in this book is applicable only to categorical propositions; and to them only the rules concerning the conversion of propositions, and concerning the figures and modes of syllogisms, are accommodated. The subsequent writers of logic have taken notice of some of the many classes of complex propositions, and have given rules adapted to them; but finding this work endless, they have left us to manage the rest by the rules of common sense.




SECT. 1. Of the Conversion of Propositions.

attempting to give some account of the Analytics and of the Topics of Aristotle, ingenuity requires me to confess, that though I have


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