STRANGER: They deny this, and say that the power of doing or suffering

is confined to becoming, and that neither power is applicable to being.

THEAETETUS: And is there not some truth in what they say?

STRANGER: Yes; but our reply will be, that we want to ascertain from

them more distinctly, whether they further admit that the soul knows,

and that being or essence is known.

THEAETETUS: There can be no doubt that they say so.

STRANGER: And is knowing and being known doing or suffering, or both,

or is the one doing and the other suffering, or has neither any share in

either?

THEAETETUS: Clearly, neither has any share in either; for if they say

anything else, they will contradict themselves.

STRANGER: I understand; but they will allow that if to know is active,

then, of course, to be known is passive. And on this view being, in

so far as it is known, is acted upon by knowledge, and is therefore in

motion; for that which is in a state of rest cannot be acted upon, as we

affirm.

THEAETETUS: True.

Sophist