not.

SOCRATES: And do you not remember that in your case and in that of
others this often occurred in the process of learning to read?

THEAETETUS: You mean that I mistook the letters and misspelt the
syllables?

SOCRATES: Yes.

THEAETETUS: To be sure; I perfectly remember, and I am very far from
supposing that they who are in this condition have knowledge.

SOCRATES: When a person at the time of learning writes the name of
Theaetetus, and thinks that he ought to write and does write Th and e;
but, again, meaning to write the name of Theododorus, thinks that he
ought to write and does write T and e--can we suppose that he knows the
first syllables of your two names?

THEAETETUS: We have already admitted that such a one has not yet
attained knowledge.

SOCRATES: And in like manner be may enumerate without knowing them the
second and third and fourth syllables of your name?

THEAETETUS: He may.

SOCRATES: And in that case, when he knows the order of the letters and
can write them out correctly, he has right opinion?

THEAETETUS: Clearly.

SOCRATES: But although we admit that he has right opinion, he will still
be without knowledge?

THEAETETUS: Yes.

SOCRATES: And yet he will have explanation, as well as right opinion,
for he knew the order of the letters when he wrote; and this we admit to
be explanation.

THEAETETUS: True.

SOCRATES: Then, my friend, there is such a thing as right opinion united
with definition or explanation, which does not as yet attain to the
exactness of knowledge.

THEAETETUS: It would seem so.

SOCRATES: And what we fancied to be a perfect definition of knowledge
is a dream only. But perhaps we had better not say so as yet, for were
there not three explanations of knowledge, one of which must, as we
said, be adopted by him who maintains knowledge to be true opinion
combined with rational explanation? And very likely there may be found
some one who will not prefer this but the third.

THEAETETUS: You are quite right; there is still one remaining. The first
was the image or expression of the mind in speech; the second, which has
just been mentioned, is a way of reaching the whole by an enumeration of
the elements. But what is the third definition?

SOCRATES: There is, further, the popular notion of telling the mark or
sign of difference which distinguishes the thing in question from all
others.

THEAETETUS: Can you give me any example of such a definition?

SOCRATES: