Return to Aristotle, On Interpretation
1. These things, however, being determined, let us consider how the affirmations and negations of that which is possible to be and not possible subsist with reference to each other; and let us also consider the contingent and non-contingent, the impossible and the necessary. For [this consideration] is attended with certain doubts.
2. For if among things connected those contradictions are opposed to each other, which are arranged according to the verb to be, and not to be; (as, for instance, the negation of this, to be a man, is, not to be a man, and not this, to be not a man; and the negation of this, to be a white man, is not to be a white man, and not this, to be not a white man; for if of every thing affirmation or negation is true, it will be true to say that wood is not a white man)–if this be the case, in those things in which the verb to be is not added, that which is asserted instead of the verb to be, will effect the same thing. Thus, for instance, of this affirmation a man walks, the negation will not be, that which is not a man walks, but a man does not walk. For it makes no difference to say a man walks, or a man is walking. Hence, if this is every where the case, the negation also of this, it is possible to be, will be, it is possible not to be, and not this, it is not possible to be.
3. But it appears that it is possible for the same thing both to be and not to be. For every thing which may be cut, or which may walk, may also not be cut, and may not walk. But the reason is, because every thing which is thus possible, does not always energize; so that negation also pertains to it. For that which is capable of walking may not walk, and that which is visible may not be seen. It is, however, impossible that opposite affirmations and negations should be verified of the same thing. Hence the negation of this, it is possible to be, is not this, it is possible not to be.
4. For it happens from these things, either that we at the same time affirm and deny the same thing of the same, or that the affirmations and negations are not made according to those additions to be, and not to be. If, therefore, that is impossible, this will be eligible. Hence, the negation of this, it is possible to be, is, it is not possible to be, and not this, it is possible not to be. There is also the same reasoning about the being contingent; for the negation of this is, not to be contingent. In a similar manner also in other things; as, for instance, in the necessary and impossible.
5. For as in those, to be, and not to be are additions, but whiteness and man are subject things; so here, to be and not to be, become as a subject; but to be possible and to be contingent are additions, which in these [enunciations] indeed, to be possible, and to be not possible, so determine the true and the false, as in those to be, and not to be.
6. But of this, it is possible not to be, the negation is not this, it is not possible to be, but this, it is not possible not to be. And of this, it is possible to be, the negation is not this, it is possible not to be, but this, it is not possible to be. Hence, these will appear to follow each other, viz. it is possible to be, and it is possible not to be. For it is the same thing to be possible to be, and not to be; since things of this kind are not contradictions of each other, viz. it is possible to be, and it is possible not to be. But it is possible to be, and it is not possible to be, are never at one and the same time verified of the same thing; for they are opposed. Neither are these, it is possible not to be, and it is not possible not to be, ever verified at one and the same time of the same thing.
7. In a similar manner of this [enunciation] it is necessary to be, the negation is not this, it is necessary not to be, [the negation] is this, it is not necessary not to be.
8. And of this, it is impossible to be, the [negation] is not this, it is impossible not to be but this, it is not impossible to be. But of this, it is impossible not to be, [the negation] is this, it is not impossible not to be.
9. And universally, as we have said, it is necessary that to be and not to be should be considered as subjects, but that affirmation and negation, which produce these, should be co-arranged with to be, and not to be. It is also requisite to think that these are opposite affirmations and negations; viz. possible, not possible; contingent, not contingent; impossible, not impossible; necessary, not necessary; true, not true.
Return to Aristotle, On Interpretation
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