STRANGER: And as we cannot admit that a man speaks and says nothing, he who says 'not-being' does not speak at all. THEAETETUS: The difficulty of the argument can no further go. STRANGER: Not yet, my friend, is the time for such a word; for there still remains of all perplexities the first and greatest, touching the very foundation of the matter. THEAETETUS: What do you mean? Do not be afraid to speak. STRANGER: To that which is, may be attributed some other thing which is? THEAETETUS: Certainly. STRANGER: But can anything which is, be attributed to that which is not? THEAETETUS: Impossible. STRANGER: And all number is to be reckoned among things which are? THEAETETUS: Yes, surely number, if anything, has a real existence. STRANGER: Then we must not attempt to attribute to not-being number either in the singular or plural? THEAETETUS: The argument implies that we should be wrong in doing so. STRANGER: But how can a man either express in words or even conceive in thought things which are not or a thing which is not without number? THEAETETUS: How indeed? STRANGER: When we speak of things which are not, are we not attributing plurality to not-being? THEAETETUS: Certainly. STRANGER: But, on the other hand, when we say 'what is not,' do we not attribute unity? THEAETETUS: Manifestly. STRANGER: Nevertheless, we maintain that you may not and ought not to attribute being to not-being? THEAETETUS: Most true. STRANGER: Do you see, then, that not-being in itself can neither be spoken, uttered, or thought, but that it is unthinkable, unutterable, unspeakable, indescribable? THEAETETUS: Quite true. STRANGER: But, if so, I was wrong in telling you just now that the difficulty which was coming is the greatest of all. THEAETETUS: What! is there a greater still behind? STRANGER: Well, I am surprised, after what has been said already, that you do not see the difficulty in which he who would refute the notion of not-being is involved. For he is compelled to contradict himself as soon as he makes the attempt. THEAETETUS: What do you mean? Speak more clearly. STRANGER: Do not expect clearness from me. For I, who maintain that not-being has no part either in the one or many, just now spoke and am still speaking of not-being as one; for I say 'not-being.' Do you understand? THEAETETUS: Yes. STRANGER: And a little while ago I said that not-being is unutterable, unspeakable, indescribable: do you follow? THEAETETUS: I do after a fashion. STRANGER: When I introduced the word 'is,' did I not contradict what I said before? THEAETETUS: Clearly. STRANGER: And in using the singular verb, did I not speak of not-being as one? THEAETETUS: Yes. STRANGER: And when I spoke of not-being as indescribable and unspeakable and unutterable, in using each of these words in the singular, did I not refer to not-being as one? THEAETETUS: Certainly.