demus, this of yours! and will you
explain how I possess that knowledge for which we were seeking? Do
you mean to say that the same thing cannot be and also not be; and
therefore, since I know one thing, that I know all, for I cannot be
knowing and not knowing at the same time, and if I know all things, then
I must have the knowledge for which we are seeking--May I assume this to
be your ingenious notion?

Out of your own mouth, Socrates, you are convicted, he said.

Well, but, Euthydemus, I said, has that never happened to you? for if I
am only in the same case with you and our beloved Dionysodorus, I cannot
complain. Tell me, then, you two, do you not know some things, and not
know others?

Certainly not, Socrates, said Dionysodorus.

What do you mean, I said; do you know nothing?

Nay, he replied, we do know something.

Then, I said, you know all things, if you know anything?

Yes, all things, he said; and that is as true of you as of us.

O, indeed, I said, what a wonderful thing, and what a great blessing!
And do all other men know all things or nothing?

Certainly, he replied; they cannot know some things, and not know
others, and be at the same time knowing and not knowing.

Then what is the inference? I said.

They all know all things, he replied, if they know one thing.

O heavens, Dionysodorus, I said, I see now that you are in earnest;
hardly have I got you to that point. And do you really and truly know
all things, including carpentering and leather-cutting?

Certainly, he said.

And do you know stitching?

Yes, by the gods, we do, and cobbling, too.

And do you know things such as the numbers of the stars and of the sand?

Certainly; did you think we should say No to that?

By Zeus, said Ctesippus, interrupting, I only wish that you would give
me some proof which would enable me to know whether you speak truly.

What proof shall I give you? he said.

Will you tell me how many teeth Euthydemus has? and Euthydemus shall
tell how many teeth you have.

Will you not take our word that we know all things?

Certainly not, said Ctesippus: you must further tell us this one thing,
and then we shall know that you are speak the truth; if you tell us
the number, and we count them, and you are found to be right, we will
believe the rest. They fancied that Ctesippus was making game of them,
and they refused, and they would only say in answer to each of his
questions, that they knew all things. F