We may observe therefore, that all propositions are either affirmative or negative; nor is it less evident, that in both cases they may be universal or particular. Hence arises that celebrated fourfold division of them into universal affirmative, and universal negative, particular affirmative, and particular negative, which comprehends all their varieties. The utility of this mode of distinction will appear more evident, when we come to speak of reasoning and syllogism.

"God

Propositions are either absolute or conditional. The absolute are those, wherein we affirm some property inseparable from the idea of the subject, and which therefore belongs to it in all possible cases; as is infinitely wise,”- "Virtue tends to the ultimate happiness of man." But when the predicate is not necessarily connected with the idea of the subject, unless upon some consideration distinct from that idea, then the proposition is called conditional. The reason of the name is taken from the supposition annexed, and may be expressed as such; thus-"If a stone is exposed to the rays of the sun, it will contract some degree of heat."

Nothing is more important in the acquisition of accurate knowledge, than a due attention to this division of propositions. If we are careful never to affirm things absolutely, but when the ideas are inseparably united and if in our other judgments we distinctly mark the conditions, which determine the predicate to belong to the subject, we shall be less liable to mistake in applying general truths to particular concerns of human life.

Propositions, when only two ideas are compared together, are in general called simple, because, having but one subject and one predicate, they are the effect of a

single judgment, which admits of no subdivision. But if several ideas present themselves to our thoughts at once so that we are led to affirm the same thing of different objects, or different things of the same object, the propositions expressing these judgments are called compound; because they may be resolved into as many others, as there are subjects or predicates in the whole complex determination of the mind. Thus, "God is infinitely wise and infinitely powerful :" here there are two predicates, "infinite wisdom" and "infinite power," both affirmed of the same subject: and accordingly the proposition may be resolved into two others, which distinctly affirm these predicates.

When any proposition is presented to the mind, if the terms in which it is expressed be understood upon comparing the ideas together, the agreement or disagreement asserted is either immediately perceived or found to be too remote from the present reach of the understanding. In the first case the proposition is said to be self-evident, and requires no proof whatever; because a bare attention to the ideas themselves produces full conviction and certainty. But if the connexion or repugnance comes not so readily under the inspection of the mind we must have récourse to reasoning; and if by a clear series of proofs we can ascertain the truth proposed, insomuch that self evidence shall accompany every step of the argument, we are then able to prove our assertion, and the proposition is said to be demonstrable. When we affirm, for instance, "that it is impossible for the same thing to be and not to be," whoever understands the terms used, perceives at the first glance the truth of what is asserted, nor can he bring himself to believe the contrary. But if we say, "this world had a beginning," the assertion is, indeed, equally

true, but shines not forth with the same degree of evidence. We find great difficulty in conceiving how the world could be created out of nothing, and are not brought to a full assent to the assertion, until by reasoning we arrive at a clear view of the absurdity involved in the contrary supposition. Hence this proposition is of the kind we call demonstrable, inasmuch as its truth is not immediately perceived, but yet may be made evident, by means of others more known and obvious, whence it follows as an unavoidable consequence.

III. REASONING. It frequently happens, in com. paring our ideas together, that their agreement or disagreement cannot be discerned at first sight, espe cially if they are of such a nature, as not to admit of an exact application to each other. It therefore becomes necessary to discover some third idea, which will admit of such an application, as the present case requires; wherein if we succeed, all difficulties vanish and the relation we are in search of may be traced with ease. This manner of determining the relation between any two ideas by the intervention of a third, with which they may be compared, is what we call reasoning, and is indeed the chief instrument, by which we extend our discoveries, and enlarge our knowledge. The great art consists in finding out such intermediate ideas, as, when compared with the others in the question, will furnish evident truths; because it is only by such means we can arrive at the knowledge of what is concealed and remote.

As in the second part of logic, our judgments, when expressed by words, were called propositions; so here in the third part, the expressions of our reasoning are termed syllogisms. By a syllogism is meant an argument consisting of three propositions, so disposed, as

that the last is necessarily inferred from the two which precede it.

In the composition of a syllogism two things are to be considered, viz. its matter and its form.

The matter consists of three propositions composed of three ideas or terms variously joined. These three terms are called the major, the minor, and the middle. The predicate of the conclusion is called the major term, because it is commonly of a larger compass and more general signification than the minor term, or subject of the conclusion. The major and minor terms are called the extremes. The middle term is the third idea disposed in two propositions, in such a manner as to show the connexion between the major and minor terms in the conclusion, for which reason the middle term itself is sometimes called the argument. The proposition, which contains the predicate of the conclusion connected with the middle term, is usually called the major proposition; whereas the minor proposition connects the middle term with the subject of the conclusion, and is sometimes called the assumption. These rules are chiefly applicable to simple or categorical syllogisms, although every syllogism contains something analogous to them*.

Compound syllogisms are composed of two or more single ones, and may be resolved into them: the chief kinds are the epichirema, the dilemma, and the sorites. These figures are liable to abuse, and are often more specious than solid. The epichirema is an argument, which contains the proof of the major and the minor or both, before it draws the conclusion. This is frequently used in writing, in public speeches, and in common conversation, in order that each part of the *Watt's Logic, p. 281, 301, &c.

discourse may be confirmed, and put out of doubt, as it proceeds towards the conclusion, which was chiefly designed. Thus the oration of Cicero, for Milo, may be reduced to this figure. "It is lawful for a person to kill those who lie in wait to kill him, as is allowed by the law of nature, and the practice of mankind. But Clodius lay in wait for Milo with that intention, as appears from his guard of soldiers and his travelling armed; therefore it was lawful for Milo to kill Clodius." The dilemma divides the whole argument into all its parts or members by a disjunctive proposition, and then infers something concerning each part, which is finally inferred concerning the whole. Thus Cicero argues to prove, that all pain ought to be borne with patience." All pain is either violent or slight; if it be slight, it may easily be endured; if violent, it will certainly be short; therefore all pain ought to be borne with patience." But for this figure to be correct two things are required, 1. the full enumeration of all the particulars of a subject; 2. that it press the opponent only, and not be liable to be retorted upon the person who uses it. In the sorites several middle terms are used to connect one another successively in several propositions, till the last proposition connects its predicate with the first subject. Such is the jocular argument of Themistocles to prove that his little son governed the whole world. "My son governs his mother, his mother governs me; I govern the Athenians, the Athenians all Greece; Greece commands Europe, and Europe the world."

There is one kind of syllogism which is defective, and is called an enthymem, because only the concluclusion with one of the premises is expressed, whilst the other is reserved in the mind. This forms the