he arithmetician, if I am not
mistaken, has the conceptions of number under his hand, and can transmit
them to another.

THEAETETUS: Yes.

SOCRATES: And when transmitting them he may be said to teach them, and
when receiving to learn them, and when receiving to learn them, and when
having them in possession in the aforesaid aviary he may be said to know
them.

THEAETETUS: Exactly.

SOCRATES: Attend to what follows: must not the perfect arithmetician
know all numbers, for he has the science of all numbers in his mind?

THEAETETUS: True.

SOCRATES: And he can reckon abstract numbers in his head, or things
about him which are numerable?

THEAETETUS: Of course he can.

SOCRATES: And to reckon is simply to consider how much such and such a
number amounts to?

THEAETETUS: Very true.

SOCRATES: And so he appears to be searching into something which he
knows, as if he did not know it, for we have already admitted that he
knows all numbers;--you have heard these perplexing questions raised?

THEAETETUS: I have.

SOCRATES: May we not pursue the image of the doves, and say that the
chase after knowledge is of two kinds? one kind is prior to possession
and for the sake of possession, and the other for the sake of taking and
holding in the hands that which is possessed already. And thus, when a
man has learned and known something long ago, he may resume and get hold
of the knowledge which he has long possessed, but has not at hand in his
mind.

THEAETETUS: True.

SOCRATES: That was my reason for asking how we ought to speak when an
arithmetician sets about numbering, or a grammarian about reading? Shall
we say, that although he knows, he comes back to himself to learn what
he already knows?

THEAETETUS: It would be too absurd, Socrates.

SOCRATES: Shall we say then that he is going to read or number what he
does not know, although we have admitted that he knows all letters and
all numbers?

THEAETETUS: That, again, would be an absurdity.

SOCRATES: Then shall we say that about names we care nothing?--any one
may twist and turn the words 'knowing' and 'learning' in any way which
he likes, but since we have determined that the possession of knowledge
is not the having or using it, we do assert that a man cannot not
possess that which he possesses; and, therefore, in no case can a man
not know that which he knows, but he may get a false opinion about it;
for he may have the knowledge, not of this particular th