Book 4
13
but the problem is whether the same thing can at once be and not be man, not in name , but in fact . If man and not-man have not different meanings, clearly not being a man will mean nothing different from being a man; and so being a man will be not being a man; they will be one.
14
For to be one means, as in the case of garment and coat, that the formula is one. And if being man and being not-man are to be one, they will have the same meaning; but it has been proved above that they have different meanings. If then anything can be truly said to be man, it must be two-footed animal; for this is what man was intended to mean.
15
And if this is necessarily so, it is impossible that at the same time the same thing should not be two-footed animal. For to be necessarily so means this: that it is impossible not to be so. Thus it cannot be true to say at the same time that the same thing is and is not man.
16
And the same argument holds also in the case of not being man; because being man and being not-man have different meanings if being white and being man have different meanings (for the opposition is much stronger in the former case so as to produce different meanings).
17
And if we are told that white too means one and the same thing,i.e. the same as man. we shall say again just what we said before,Aristot. Met. 4.4.12. that in that case all things, and not merely the opposites, will be one. But if this is impossible, what we have stated follows; that is, if our opponent answers our question; but if when asked the simple question he includes in his answer the negations, he is not answering our question.
18
There is nothing to prevent the same thing from being man and white and a multitude of other things; but nevertheless when asked whether it is true to say that X is man, or not, one should return an answer that means one thing, and not add that X is white and large. It is indeed impossible to enumerate all the infinity of accidents; and so let him enumerate either all or none.
