SOCRATES: And seeing is knowing, and therefore not-seeing is not-knowing?

THEAETETUS: Very true.

SOCRATES: Then the inference is, that a man may have attained the
knowledge of something, which he may remember and yet not know, because he
does not see; and this has been affirmed by us to be a monstrous
supposition.

THEAETETUS: Most true.

SOCRATES: Thus, then, the assertion that knowledge and perception are one,
involves a manifest impossibility?

THEAETETUS: Yes.

SOCRATES: Then they must be distinguished?

THEAETETUS: I suppose that they must.

SOCRATES: Once more we shall have to begin, and ask 'What is knowledge?'
and yet, Theaetetus, what are we going to do?

THEAETETUS: About what?

SOCRATES: Like a good-for-nothing cock, without having won the victory, we
walk away from the argument and crow.

THEAETETUS: How do you mean?