Commentary Aristotle Metaphysics
But if such a person does not admit this, he will not say anything meaningful, either for himself or for someone else, and it will then be idle to dispute with him. But when he has admitted this, a demonstration will at once be possible against him; for there is straightway found to be something definite and determinate which is signified by the term distinct from its contradictory, as will become clear below. Yet this will not strictly be a demonstration of the foregoing principle, but only an argument upholding this principle against those who deny it. For he who destroys reason (that is, his own intelligible expression) by saying that a term signifies nothing, must uphold its significance, because he can express what he denies only by speaking and by signifying something.
612. First of all, then. He proceeds from the assumption he had made to prove what he intends.
First, he deals with one particular case;
second, he treats all cases in a general way, at again, if the term.
He accordingly first says that, if a term signifies something, it will be evident first of all that this proposition will be true, and that its contradictory, which he denies, will be false. Thus this at least will be true: not every affirmation is true together with its negation.
613. Now by “signifying”. Then he shows that this applies universally to all cases, namely, that contradictories are not true at the same time. In regard to this he does four things.
First, he makes certain assumptions which are necessary for drawing his intended conclusion.
Second, he draws his conclusion, at therefore, if it is true.
Third, he proves one assumption which he had made, at for “being a man”.
Fourth, he rejects a quibble, at that is to say.
First, he shows that a term signifies one thing;
second, he shows from this that the term man signifies what being a man is, but not what it is not, at it is impossible, then.
Third, he shows that the term man signifies one thing, at now if “man”.
He accordingly first says that, if the term “man” signifies one thing, let this be two-footed animal. For a term is said to signify this one thing which is the definition of the thing signified by the term, so that if two-footed animal is the being of “man” (that is, if this is what the essence of man is), this will be what is signified by the term man.
614. But if one were to say that a term signifies many things, it will signify either a finite or an infinite number of them. But if it signifies a finite number, it will differ in no way, according to another translation, from the term which is assumed to signify one thing; for it signifies many finite concepts of different things and different terms can be fitted to each single concept.
For example, if the term “man” were to signify many concepts, and the concept two-footed animal is one of them, one term is assigned to the concept man. And if there are many other concepts, many other terms may be assigned so long as those concepts are finite in number. Thus he will be forced back to the first position, that a term signifies one thing.
615. But if a term does not signify a finite number of concepts, but rather an infinite number, evidently neither reasoning nor debate will be possible. This becomes clear as follows.
Any term that does not signify one thing signifies nothing. This is proved thus. Terms signify something understood, and therefore if nothing is understood, nothing is signified. But if one thing is not understood, nothing is understood, because anyone who understands anything must distinguish it from other things. If a term does not signify one thing, then it signifies nothing at all; if terms signify nothing, discourse will be impossible, both the kind which establishes truth and the kind which refutes an assertion.
Hence it is clear that, if terms signify an infinite number of things, neither reasoning nor dispute will be possible. But if it is possible to understand one thing, a term may be given to it. So let it be held then that a term signifies something.
616. It is impossible. He proves the second point, namely, that the term “man” does not signify “not being a man.” For a term that signifies one thing signifies not only what is one in subject (and is therefore said to be one because it is predicated of one subject), but what is one absolutely, that is, in concept. For if we wanted to say that a term signifies one thing because it signifies the attributes which are verified of one thing, it would then follow that the terms “musical,” “white,” and “man” all signify one thing, since all are verified of one thing. And from this it would follow that all things are one.
For if white is predicated of man and is therefore identical with him, then when it is also predicated of a stone it will be identical with a stone. And, since those things that are identical with one and the same thing are identical with each other, it would follow that a man and a stone are one thing and have one concept. Thus the result would be that all terms are univocal, that is, one in concept, or synonymous, as another text says, that is, meaning absolutely the same thing in subject and in concept.
617. Now, although being and non-being are verified of the same subject according to those who deny the first principle, still being a man and not being a man must differ in concept, just as white and musical differ in concept even though they are verified of the same subject. Hence it is evident that being and non-being cannot be the same in concept and in subject in the sense that they are signified by one univocal term.
618. Now it must be noted that the expression “being a man” or “to be a man” or “having the being of a man” is taken here for the quiddity of man, and therefore it is concluded from this that the term “man” does not signify not being a man as its proper concept. But because he had said above that the same term can signify many things according to different concepts, he therefore adds except in an equivocal sense, in order to make clear that the term “man” does not signify in a univocal sense both being a man and not being a man, but it can signify both in an equivocal sense (that is, in the sense that what we call man in one language others might call not-man in another language). For we are not debating whether the same thing can both be and not be man in name, but whether it can in fact.
619. Now if “man”. Then he proves the third point. That the terms “man” and “not-man” do not signify the same thing, and he uses the following argument. The term “man” signifies being a man or what man is, and the term “not-man” signifies not being a man or what man is not. If, then, “man” and “not-man” do not signify something different, being a man will not differ from not being a man, or being a not-man, and therefore one of these will be predicated of the other. And they will also have one concept, for when we say that some terms signify one thing, we mean that they signify one concept, as the terms “clothing” and “garment” do. Hence, if being a man and not being a man are one in this way, that is, in concept, there will then be one concept which will signify both being a man and not being a man. But it has been granted or demonstrated that the term which signifies each is different; for it has been shown that the term “man” signifies man and does not signify not-man. Thus it is clear that being a man and not being a man do not have a single concept, and therefore the thesis that “man” and “not-man” signify different things becomes evident.
620. Therefore, if it is true. Here he proves his main thesis from the assumptions made earlier, and he uses the following argument. A man must be a two-footed animal, as is true from the foregoing, for this is the concept which the term “man” signifies. But what is necessary cannot not be, for this is what the term necessary means—namely, unable not to be, or incapable of not being, or impossible not to be. Hence it is not possible, or incapable, or impossible for man not to be a two-footed animal. Therefore, it is evident that the affirmation and the negation cannot both be true—that is, it cannot be true that man is both a two-footed animal and not a two-footed animal. The same reasoning based on the meanings of terms can be understood to apply to what is not-man, because what is not-man must be not a two-footed animal, since this is what the term signifies. Therefore, it is impossible that a not-man should be a two-footed animal.
621. Now the things demonstrated above are useful to his thesis, because if someone were to think that the terms “man” and “not-man” might signify the same thing, or that the term “man” might signify both being a man and not being a man, his opponent could deny the proposition that man must be a two-footed animal. For he could say that it is no more necessary to say that man must be a two-footed animal than to say that he is not a two-footed animal, granted that the terms “man” and “not-man” signify the same thing, or granted that the term “man” signifies both of these, being a man and not being a man.
622. For “being a man”. Then he proves one of the assumptions which he had made, for in order to prove that the term “man” does not signify not being a man, he assumed that being a man and not being a man are different, even though they might be verified of the same subject. His aim here is to prove this by the following argument. There is greater opposition between being a man and not being a man than between “man” and “white”; but “man” and “white” have different concepts, although they may be the same in subject. Therefore, being a man and not being a man also have different concepts.