Dialogues

partisans of “the whole” appear to speak more truly, we will fly off from the party which would move the immovable, to them. And if I find that neither of them have anything reasonable to say, we shall be in a ridiculous position, having so great a conceit of our own poor opinion and rejecting that of ancient and famous men. O Theodorus, do you think that there is any use in proceeding when the danger is so great? Theodorus Nay, Socrates, not to examine thoroughly what the two parties have to say would be quite intolerable. Socrates Then examine we must, since you, who were so reluctant to begin, are so eager to proceed. The nature of motion appears to be the question with which we begin. What do they mean when they say that all things are in motion? Is there only one kind of motion, or, as I rather incline to think, two? I should like to have your opinion upon this point in addition to my own, that I may err, if I must err, in your company; tell me, then, when a thing changes from one place to another, or goes round in the same place, is not that what is called motion? Theodorus Yes. Socrates Here then we have one kind of motion. But when a thing, remaining on the same spot, grows old, or becomes black from being white, or hard from being soft, or undergoes any other change, may not this be properly called motion of another kind? Theodorus I think so. Socrates Say rather that it must be so. Of motion then there are these two kinds, “change,” and “motion in place.”318 Theodorus You are right. Socrates And now, having made this distinction, let us address ourselves to those who say that all is motion, and ask them whether all things according to them have the two kinds of motion, and are changed as well as move in place, or is one thing moved in both ways, and another in one only? Theodorus Indeed, I do not know what to answer; but I think they would say that all things are moved in both ways. Socrates Yes, comrade; for, if not, they would have to say that the same things are in motion and at rest, and there would be no more truth in saying that all things are in motion, than that all things are at rest. Theodorus To be sure. Socrates And if they are to be in motion, and nothing is to be devoid of motion, all things must always have every sort of motion? Theodorus Most true. Socrates Consider a further point: did we not understand them to explain the generation of heat, whiteness, or anything else, in some such manner as the following:⁠—were they not saying that each of them is moving between the agent and the patient, together with a perception, and that the patient ceases to be a perceiving power and becomes a percipient, and the agent a quale instead of a quality? I suspect that quality may appear a strange and uncouth term to you, and that you do not understand the abstract expression. Then I will take concrete instances: I mean to say that the producing power or agent becomes neither heat nor whiteness but hot and white, and the like of other things. For I must repeat what I said before, that neither the agent nor patient have any absolute existence, but when they come together and generate sensations and their objects, the one becomes a thing of a certain quality, and the other a percipient. You remember? Theodorus Of course. Socrates We may leave the details of their theory unexamined, but we must not forget to ask them the only question with which we are concerned: Are all things in motion and flux? Theodorus Yes, they will reply. Socrates And they are moved in both those ways which we distinguished, that is to say, they move in place and are also changed? Theodorus Of course, if the motion is to be perfect. Socrates If they only moved in place and were not changed, we should be able to say what is the nature of the things which are in motion and flux? Theodorus Exactly. Socrates But now, since not even white continues to flow white, and whiteness itself is a flux or change which is passing into another colour, and is never to be caught standing still, can the name of any colour be rightly used at all? Theodorus How is that possible, Socrates, either in the case of this or of any other quality⁠—if while we are using the word the object is escaping in the flux? Socrates And what would you say of perceptions, such as sight and hearing, or any other kind of perception? Is there any stopping in the act of seeing and hearing? Theodorus Certainly not, if all things are in motion. Socrates Then we must not speak of seeing any more than of not-seeing, nor of any other perception more than of any non-perception, if all things partake of every kind of motion? Theodorus Certainly not. Socrates Yet perception is knowledge: so at least Theaetetus and I were saying. Theodorus Very true. Socrates Then when we were asked what is knowledge, we no more answered what is knowledge than what is not knowledge? Theodorus I suppose not. Socrates Here, then, is a fine result: we corrected our first answer in our eagerness to prove that nothing is at rest. But if nothing is at rest, every answer upon whatever subject is equally right: you may say that a thing is or is not thus; or, if you prefer, “becomes” thus; and if we say “becomes,” we shall not then hamper them with words expressive of rest. Theodorus Quite true. Socrates Yes, Theodorus, except in saying “thus” and “not thus.” But you ought not to use the word “thus,” for there is no motion in “thus” or in “not thus.” The maintainers of the doctrine have as yet no words in which to express themselves, and must get a new language. I know of no