UNIVERSAL; UNIVERSAL AND PARTICULAR (Logic). By a universal, in old logic, is meant a term which stands for more things than one : that is, any word which means more than an individual, which applies to a class of objects. In this manner it was applied to he five PREDICABLES, which were also called universals. For the lispute about the character of universals, see ; but this lispute belongs to metaphysics, not to logic.
The distinction of universal and particular, as applied to propositions, uses the word universal in a different sense. A proposition is universal when it makes its assertion or denial about every one of the things Token of ; and particular when it makes such an assertion or denial of some as implies that others are, or may be,left unspoken of. Thus" all men are mortal" is universal, and also "no man is perfect." But "some men are born in England' and "some animals cannot live in this climate" are particular. These are the direct logical forms, but it happens commonly that the universal and particular characters are ex pressed by a great variety of idiomatic turns, and even that forms of expression which, literally speaking, imply universality, are used in a particular sense. Thus "men do not willingly abandon life" strictly means that all men are unwilling to quit life : nevertheless it would be generally understood to speak of most men—all but a few. Except when speaking of laws of nature or necessary conditions of the mind, few writers have much occasion for universal propositions, and con sequently the forms of speech which belong to all, pass into use when the proposition is intended to be predicated only of most.
The particular proposition, in its pure logical form, is of no very com mon occurrence. The reader must understand that all which is not mentioned is, in the science of login, considered as unspoken of : now the particular proposition of common life generally denies of the rest what it affirms of some, or affirms of the rest what it denies of some. Thus he who should say " some men are mortal " would be held to utter an untruth, because he would be thought to imply that the rest are not ; and a naturalist, wishing to state that some species of a certain animal have fur, in order to state just what his argument requires, would think it necessary to say "some at least," or to use some other form of speech which would signify that, for anything he said to the contrary, all the other species might have fur also. But the logical proposition
is always understood to make all possible admission or allowance as to every matter which is not directly spoken of ; and " some men are mortal" means that nothing whatever is either said or implied about the rest.
The most common form of speech perhaps is the one compounded of the two particular propositions, the affirmative and the negative, of which the emphatio part is expressed, and the rest implied. Thus, two men going into a company, the first expecting to see all dressed in mourning, and the second thinking none would be so, would come away expressing the same fact in sentences of very different meaning. The first would say "some were not in mourning," the second would say " some were in mourning," both meaning to say " some were and some were not," but each giving only that part of the assertion which contained the (to him) unexpected fact: It would be desirable that writers on logic should make a closer analysis of the common forms of speech, and a comparison of them with the strict and true logical forms.
The universal proposition includes all cases in which there is nothing left unspoken of, and therefore contains all propositions in which the subject ie an individual, or cannot be divided into parts. Thus, "Milton was an Englishman" is as much a universal proposition as "all men are mortal." It was at one time a matter of discussion whether propositions asserting matter of individuals could he properly called universal ; but whether this term were applicable or not, it was always seen that the rules of deduction applying to such propositions were precisely those which obtain in propositions about the appella tion of which no doubt could exist. But the preceding proposition is not universal because it includes all Milton, but because it includes all Miltons : that is, all Miltons who can answer to a description which is implied in the word as there used. And if, by the closeness of the implied definition, and the number of conditions which are to be fulfilled, there be left but one of men alive or dead whom it is possible to mean, the proposition is not the less true. Thus, when every A is shown to be n, and every 13 to be c, it follows that every A is C, even though the description given of A be so close that there can be found but one object answering to it in the world.