Return to Aristotle, On Interpretation
1. Since, however, some things are universals, but others are particulars, I call that thing “universal” which is adapted by its nature to be predicated of a multitude (or class) of things, but that “particular” (or individual) which is not adapted to be so predicated; as “man” is a universal, but “Callias” a particular (or individual) thing. It is necessary to enunciate that something is inherent or is not inherent, at one time in something universal, but at another in something particular.
2. If, therefore, any one enunciates in a universal way (i.e., universally) of that which is universal, that something is inherent, or is not inherent, these enunciations will be contrary. But I say, to enunciate universally of that which is universal; as, for instance: Every man is white. No man is white.
3. But when he enunciates of universal subjects not in a universal way, these enunciations are not contrary. The things signified, may, however, sometimes be contrary. But I say, to enunciate not universally of universal things; as, for instance: Man is white.((Here, the noun “man” is a universal, but the enunciation does not speak universally of this universal noun.)) Man is not white. For “man” being a universal (i.e., the name of a genus), is not used as a universal in the enunciation; since the word “every” does not signify a universal, but shows that the subject is universally assumed.
4. Of that, however, which is universally predicated, the universal predicate is not true. For no affirmation will be true, in which the universal is predicated of that which is universally predicated; as for instance: Every man is every animal.
5. I say, therefore, that affirmation is opposed to negation contradictorily; the affirmation which signifies a universal, to that which signifies that the same is not to be universally assumed; as: Every man is white. vs. Not every man is white. No man is white. vs. Some man is white. But the affirmation of a universal, and the negation of a universal, are opposed contrarily; as: Every man is white. vs. No man is white. Every man is just. vs. No man is just.
6. Hence it is impossible that these should be at one and the same time true.
7. It may sometimes, however, happen, that the opposites to these are co-verified in the same thing: as: Not every man is white. Some man is white.
8. Of such contradictions, therefore, of universals are universally made, it is necessary that one of them should be true of false;
9. And also such as are of particulars; as: Socrates is white. Socrates is not white.
10. But with respect to such contradictions as are of universals, indeed, yet are not universally made, the one is not always true, but the other false. For at one and the same time it may be truly said, man is white, and man is not white; and man is beautiful, and man is not beautiful; for if he is deformed he is not beautiful; and if any thing is becoming to be, it is not. This, however, may immediately appear to be absurd, because this assertion, man is not white, seems at the same time to signify the same thing, as no man is white. It neither, however, necessarily signifies the same thing, nor at the same time.
11. But it is evident, that there is one negation of one affirmation; for it is necessary that the same thing (i. e. the attribute) should deny the negation which affirmation affirmed; and also from the same, (i. e. subject) viz. either from some particular, or some universal, either as universal, or as not universal. I say, as, for instance: Socrates is white. Socrates is not white. But if there is something else from the same, or the same thing from something else, that enunciation will not be opposite, but different from it. To this enunciation, however, Every man is white. the enunciation, Not every man is white. is opposed. But to this: A certain man is white. the enunciation is opposed: No man is white.
12. And thus we have shown that one affirmation is contradictorily opposed to one negation, and also what these are. We have likewise shown there are other contraries, and what they are; and that not every contradiction is true or false, and why it is not, and when it is true or false.
Return to Aristotle, On Interpretation
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