GER: Let us push the question; for if they will admit that any,
even the smallest particle of being, is incorporeal, it is enough; they
must then say what that nature is which is common to both the corporeal
and incorporeal, and which they have in their mind's eye when they say
of both of them that they 'are.' Perhaps they may be in a difficulty;
and if this is the case, there is a possibility that they may accept a
notion of ours respecting the nature of being, having nothing of their
own to offer.

THEAETETUS: What is the notion? Tell me, and we shall soon see.

STRANGER: My notion would be, that anything which possesses any sort
of power to affect another, or to be affected by another, if only for a
single moment, however trifling the cause and however slight the effect,
has real existence; and I hold that the definition of being is simply
power.

THEAETETUS: They accept your suggestion, having nothing better of their
own to offer.

STRANGER: Very good; perhaps we, as well as they, may one day change our
minds; but, for the present, this may be regarded as the understanding
which is established with them.

THEAETETUS: Agreed.

STRANGER: Let us now go to the friends of ideas; of their opinions, too,
you shall be the interpreter.

THEAETETUS: I will.

STRANGER: To them we say--You would distinguish essence from generation?

THEAETETUS: 'Yes,' they reply.

STRANGER: And you would allow that we participate in generation with the
body, and through perception, but we participate with the soul through
thought in true essence; and essence you would affirm to be always the
same and immutable, whereas generation or becoming varies?

THEAETETUS: Yes; that is what we should affirm.

STRANGER: Well, fair sirs, we say to them, what is this participation,
which you assert of both? Do you agree with our recent definition?

THEAETETUS: What definition?

STRANGER: We said that being was an active or passive energy, arising
out of a certain power which proceeds from elements meeting with one
another. Perhaps your ears, Theaetetus, may fail to catch their answer,
which I recognize because I have been accustomed to hear it.

THEAETETUS: And what is their answer?

STRANGER: They deny the truth of what we were just now saying to the
aborigines about existence.

THEAETETUS: What was that?

STRANGER: Any power of doing or suffering in a degree however slight was
held by us to be a sufficient definition of being?

THE