THEAETETUS
© George MacDonald Ross, 1975–1999
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<c1> SOCRATES. [156D] Do you now understand why things are as they are according to the doctrine I have attributed to Protagoras, or do you still not understand?
THEAETETUS. I don’t think I do.
SOCRATES. Then will you be grateful to me if I help you to find out the secret truth in the thinking of a famous man, or rather a number of famous men?
THEAETETUS. [156E] How could I not be grateful — indeed, extremely grateful?
<c2> SOCRATES. Well, just look around and check that no-one uninitiated is eavesdropping. By the ‘uninitiated,’ I mean those who think that nothing exists unless they can grasp it firmly with their hands, and who reject actions, changes, and anything invisible as having no share in reality.
<c3> THEAETETUS. Certainly, Socrates, you are talking about hard and impenetrable people.
SOCRATES. [156A] Yes, my boy, they are completely uncultured.
<c4> But the ones whose secrets I’m going to reveal to you are much smarter. Their fundamental principle (on which everything I was talking about earlier depends) is that everything is motion, and nothing else exists.
<c5> There are two kinds of motion, each with an infinity of instances: one which has the power to act, and another which has the capacity to be acted upon.
<c6> Their intercourse and rubbing together gives birth to innumerable offspring; but they are always twins: that which is sensed, and the sensation which is always born together with that which is sensed. [156B] For these sensations we have names, and they are called ‘seeings’, ‘hearings’, ‘smellings’, ‘cold feelings’, ‘warm feelings’, ‘pleasures’, ‘pains’, ‘desires’, ‘fears’, and countless others which have no name (although there are very many which do have names). Things which are sensed are born in the same birth as each of these sensations. For example, various colours are born with various seeings, and sounds with hearings; and everything else which is sensed has a twin birth with a sensation.
[156C] Now, Theaetetus, what does this story tell us about what we were discussing before? Do you understand?
THEAETETUS. Not really, Socrates.
SOCRATES. Well listen, and see if we can finish the story.
<c7> It means that, as I was saying, all these things are motions, and their motion is either quick or slow. The slow motion stays in the same place, and is directed towards anything which approaches it. [156D] This is how it gives birth, and what it gives birth to are faster motions. These move, and in moving give birth to motion.
<c8> So when the eye and something appropriate to it approach each other, they give birth both to whiteness and to its twin sensation. These could not have been born if either the eye or what it saw had gone to anything else. It is at this point that, between the motions, both of vision towards the eyes, and of whiteness towards that which simultaneously gives birth to the colour, [156E] the eye becomes filled with vision, and then sees, and becomes, not vision, but a seeing eye; and that which simultaneously gives birth to the colour is suffused with whiteness, and becomes, not whiteness, but a white thing — whether wood, stone, or whatever else happens to be coloured with such a colour. All the others must be understood in the same way: the hard, the warm, and everything.
<c9> As I said earlier, a thing in itself is nothing. [157A] Everything comes into being through mutual interaction, and the whole variety of things arises from motion. It’s very iffy (as they say) to conceive of the active motion or the passive motion as things existing independently. For the active isn’t anything until it has something passive to act upon, and the passive isn’t anything until it has something active to be acted upon by. And something which is active in one interaction can emerge as passive when interacting with something else.
<c10> So it follows from all this, as I said from the start, that nothing exists as a self-contained unity, but is always becoming something for someone. [157B] Indeed, the word ‘exist’ should be completely abolished, even though I myself have often been forced to use it (even just now) by habit and carelessness. I shouldn’t have done so; nor (as wise people say) should we allow the use of any other words which imply stability, such as ‘something’, ‘somebody’s’, ‘mine’, ‘this’, or ‘that’. Instead we should speak in accordance with nature, and use expressions like ‘coming into being’, ‘acting’, ‘dissolving’, and ‘changing’, since anyone is easily refuted if they think they can freeze anything in speech. And we should speak this way, not only in the case of individual things, but also in the case of collectives of many things, such as ‘humanity’, ‘stone’, or different species of animal. . . .
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