r perception is or is not the
same as knowledge; for this was the real point of our argument, and with
a view to this we raised (did we not?) those many strange questions.

THEAETETUS: Certainly.

SOCRATES: Shall we say that we know every thing which we see and hear?
for example, shall we say that not having learned, we do not hear the
language of foreigners when they speak to us? or shall we say that
we not only hear, but know what they are saying? Or again, if we see
letters which we do not understand, shall we say that we do not see
them? or shall we aver that, seeing them, we must know them?

THEAETETUS: We shall say, Socrates, that we know what we actually see
and hear of them--that is to say, we see and know the figure and colour
of the letters, and we hear and know the elevation or depression of the
sound of them; but we do not perceive by sight and hearing, or know,
that which grammarians and interpreters teach about them.

SOCRATES: Capital, Theaetetus; and about this there shall be no dispute,
because I want you to grow; but there is another difficulty coming,
which you will also have to repulse.

THEAETETUS: What is it?

SOCRATES: Some one will say, Can a man who has ever known anything, and
still has and preserves a memory of that which he knows, not know that
which he remembers at the time when he remembers? I have, I fear, a
tedious way of putting a simple question, which is only, whether a man
who has learned, and remembers, can fail to know?

THEAETETUS: Impossible, Socrates; the supposition is monstrous.

SOCRATES: Am I talking nonsense, then? Think: is not seeing perceiving,
and is not sight perception?

THEAETETUS: True.

SOCRATES: And if our recent definition holds, every man knows that which
he has seen?

THEAETETUS: Yes.

SOCRATES: And you would admit that there is such a thing as memory?

THEAETETUS: Yes.

SOCRATES: And is memory of something or of nothing?

THEAETETUS: Of something, surely.

SOCRATES: Of things learned and perceived, that is?

THEAETETUS: Certainly.

SOCRATES: Often a man remembers that which he has seen?

THEAETETUS: True.

SOCRATES: And if he closed his eyes, would he forget?

THEAETETUS: Who, Socrates, would dare to say so?

SOCRATES: But we must say so, if the previous argument is to be
maintained.

THEAETETUS: What do you mean? I am not quite sure that I understand you,
though I have a strong suspicion that you are right.

SOCRATES: As thus: h