Str. Then it is in some region like this that we shall always, both now and hereafter, discover the philosopher, if we look for him; 
 he also is hard to see clearly, but the difficulty is not the same in his case and that of the sophist. Theaet. How do they differ? Str. The sophist runs away into the darkness of not-being, feeling his way in it by practice, By practice, i.e., by empirical knowledge as opposed to reason. and is hard to discern on account of the darkness of the place. Don’t you think so? Theaet. It seems likely. Str. But the philosopher, always devoting himself through reason to the idea of being, is also very difficult to see on account of the brilliant light of the place; for the eyes
 of the soul of the multitude are not strong enough to endure the sight of the divine. Theaet. This also seems no less true than what you said about the sophist. Str. Now we will make more accurate investigations about the philosopher hereafter, if we still care to do so; but as to the sophist, it is clear that we must not relax our efforts until we have a satisfactory view of him. Theaet. You are right. Str. Since, therefore, we are agreed that some of the classes will mingle with one another, and others will not, and some will mingle with few and others with many, and that
 there is nothing to hinder some from mingling universally with all, let us next proceed with our discussion by investigating, not all the forms or ideas, lest we become confused among so many, but some only, selecting them from those that are considered the most important; let us first consider their several natures, then what their power of mingling with one another is, and so, if we cannot grasp being and not-being with perfect clearness, we shall at any rate not fail to reason fully about them, so far as the method of our present inquiry permits. Let us in this way see whether it is, after all,
 permitted us to say that not-being really is, although not being, and yet come off unscathed. Theaet. Yes; that is the proper thing for us to do. Str. The most important, surely, of the classes or genera are those which we just mentioned; being itself and rest and motion. Theaet. Yes, by far. Str. And further, two of them, we say, cannot mingle with each other. Theaet. Decidedly not. Str. But being can mingle with both of them, for they both are. Theaet. Of course. Str. Then these prove to be three. Theaet. To be sure. Str. Each of them is, then, other than the remaining two, but the same as itself. Theaet. Yes. Str. But what do we mean by these words, the same and other, which we have just used? Are they two new classes, different from the other three, but always of necessity mingled with them, and must we conduct our inquiry on the assumption that there are five classes, not three, or are we unconsciously speaking of one of those three
 when we say the same or other ? Theaet. Perhaps. Str. But certainly motion and rest are neither other nor the same. Theaet. How so? Str. Whatever term we apply to rest and motion in common cannot be either of those two. Theaet. Why not? Str. Because motion would be at rest and rest would be in motion; in respect of both, for whichever of the two became other would force the other to change its nature into that of its opposite, since
 it would participate in its opposite. Theaet. Exactly so. Str. Both certainly partake of the same and the other. i.e., sameness and difference can he predicated of both. Theaet. Yes. Str. Then we must not say that motion, or rest either, is the same or other. Theaet. No. Str. But should we conceive of being and the same as one? Theaet. Perhaps. Str. But if being and the same have no difference of meaning, then when we go on and say that both rest and motion are, we shall be saying that they are both the same,
 since they are. Theaet. But surely that is impossible. Str. Then it is impossible for being and the same to be one. Theaet. Pretty nearly. Str. So we shall consider the same a fourth class in addition to the other three? Theaet. Certainly. Str. Then shall we call the other a fifth class? Or must we conceive of this and being as two names for one class? Theaet. May be. Str. But I fancy you admit that among the entities some are always conceived as absolute, and some as relative. Theaet. Of course. Str. And other is always relative to other, is it not? Theaet. Yes. Str. It would not be so, if being and the other were not utterly different. If the other, like being, partook of both absolute and relative existence, there would be also among the others that exist another not in relation to any other; but as it is, we find that whatever is other is just what it is through compulsion of some other. Theaet. The facts are as you say. Str. Then we must place the nature of the other as a fifth
 among the classes in which we select our examples. Theaet. Yes. Str. And we shall say that it permeates them all; for each of them is other than the rest, not by reason of its own nature, but because it partakes of the idea of the other. Theaet. Exactly. Str. Let us now state our conclusions, taking up the five classes one at a time. Theaet. How? Str. Take motion first; we say that it is entirely other than rest, do we not? Theaet. We do. Str. Then it is not rest. Theaet. Not at all. Str. But it exists, by reason of its participation in being. Theaet. Yes, it exists. Str. Now motion again is other than the same. Theaet. You’re about right. Str. Therefore it is not the same. Theaet. No, it is not. Str. But yet we found it was the same, because all things partake of the same. Theaet. Certainly. Str. Then we must admit that motion is the same and is not the same, and we must not be disturbed thereby; for when we say it is the same and not the same, we do not use the words alike. When we call it the same, we do so because it partakes
 of the same in relation to itself, and when we call it not the same, we do so on account of its participation in the other, by which it is separated from the same and becomes not that but other, so that it is correctly spoken of in turn as not the same. Theaet. Yes, certainly. Str. Then even if absolute motion partook in any way of rest, it would not be absurd to say it was at rest? Theaet. It would be perfectly right, if we are to admit that some of the classes will mingle with one another, and others will not. Str. And surely we demonstrated that before we took up our present points; we proved that it was according to nature. See Plat. Theaet. 251e ff Theaet. Yes, of course. Str. Then let us recapitulate: Motion is other than the other, just as we found it to be other than the same and than rest. Is that true? Theaet. Inevitably. Str. Then it is in a sense not other and also other, according to our present reasoning. Theaet. True. Str. Now how about the next point? Shall we say next that motion is other than the three, but not other than the fourth,—that is, if we have agreed that the classes
 about which and within which we undertook to carry on our inquiry are five in number? Theaet. How can we say that? For we cannot admit that the number is less than was shown just now. Str. Then we may fearlessly persist in contending that motion is other than being? Theaet. Yes, most fearlessly. Str. It is clear, then, that motion really is not, and also that it is, since it partakes of being? Theaet. That is perfectly clear. Str. In relation to motion, then, not-being is. That is inevitable. And this extends to all the classes; for in all of them
 the nature of other so operates as to make each one other than being, and therefore not-being. So we may, from this point of view, rightly say of all of them alike that they are not; and again, since they partake of being, that they are and have being. Theaet. Yes, I suppose so. Str. And so, in relation to each of the classes, being is many, and not-being is infinite in number. Being is many, for each and every thing in all the classes is; but not-being is infinite, for not only is it true that everything in each of the classes is not, but not-being extends also to all conceptions which do not and cannot have any reality. Theaet. So it seems.