retort upon us:-"O my excellent friends, he will say, laughing, if a
man knows the form of ignorance and the form of knowledge, can he
think that one of them which he knows is the other which he knows? or,
if he knows neither of them, can he think that the one which he
knows not is another which he knows not? or, if he knows one and not
the other, can he think the one which he knows to be the one which
he does not know? or the one which he does not know to be the one
which he knows? or will you tell me that there are other forms of
knowledge which distinguish the right and wrong birds, and which the
owner keeps in some other aviaries or graven on waxen blocks according
to your foolish images, and which he may be said to know while he
possesses them, even though he have them not at hand in his mind?
And thus, in a perpetual circle, you will be compelled to go round and
round, and you will make no progress." What are we to say in reply,
Theaet. Indeed, Socrates, I do not know what we are to say.
Soc. Are not his reproaches just, and does not the argument truly
show that we are wrong in seeking for false opinion until we know what
knowledge is; that must be first ascertained; then, the nature of
Theaet. I cannot but agree with you, Socrates, so far as we have yet
Soc. Then, once more, what shall we say that knowledge is?-for we
are not going to lose heart as yet.
Theaet. Certainly, I shall not lose heart, if you do not.
Soc. What definition will be most consistent with our former views?
Theaet. I cannot think of any but our old one, Socrates.
Soc. What was it?
Theaet. Knowledge was said by us to be true opinion; and true
opinion is surely unerring, and the results which follow from it are
all noble and good.
Soc. He who led the way into the river, Theaetetus, said "The
experiment will show"; and perhaps if we go forward in the search,
we may stumble upon the thing which we are looking for; but if we stay
where we are, nothing will come to light.
Theaet. Very true; let us go forward and try.
Soc. The trail soon comes to an end, for a whole profession is
Theaet. How is that, and what profession do you mean?
Soc. The profession of the great wise ones who are called orators
and lawyers; for these persuade men by their art and make them think
whatever they like, but they do not teach them. Do you imagine that
there are any teachers in the world so clever as to be able to
convince others of the truth about acts of robbery or violence, of
which they were not eyewitnesses, while a little water is flowing in
Theaet. Certainly not, they can only persuade them.
Soc. And would you not say that persuading them is making them
have an opinion?
Theaet. To be sure.
Soc. When, therefore, judges are justly persuaded about matters
which you can know only by seeing them, and not in any other way,
and when thus judging of them from report they attain a true opinion
about them, they judge without knowledge and yet are rightly
persuaded, if they have judged well.
Soc. And yet, O my friend, if true opinion in law courts and
knowledge are the same, the perfect judge could not have judged
rightly without knowledge; and therefore I must infer that they are
not the same.
Theaet. That is a distinction, Socrates, which I have heard made
by some one else, but I had forgotten it. He said that true opinion,
combined with reason, was knowledge, but that the opinion which had no
reason was out of the sphere of knowledge; and that things of which