euthydemus   

Again I replied, Through ignorance I have answered too much, but I
hope that you will forgive me. And now I will answer simply that I
always know what I know with something.
And is that something, he rejoined, always the same, or sometimes one
thing, and sometimes another thing?
Always, I replied, when I know, I know with this.
Will you not cease adding to your answers?
My fear is that this word "always" may get us into trouble.
You, perhaps, but certainly not us. And now answer: Do you always know
with this?
Always; since I am required to withdraw the words "when I know."
You always know with this, or, always knowing, do you know some things
with this, and some things with something else, or do you know all
things with this?
All that I know, I replied, I know with this.
There again, Socrates, he said, the addition is superfluous.
Well, then, I said, I will take away the words that I know."
Nay, take nothing away; I desire no favours of you; but let me ask:
Would you be able to know all things, if you did not know all things?
Quite impossible.
And now, he said, you may add on whatever you like, for you confess
that you know all things.
I suppose that is true, I said, if my qualification implied in the
words "that I know" is not allowed to stand; and so I do know all
things.
And have you not admitted that you always know all things with that
which you know, whether you make the addition of "when you know them"
or not? for you have acknowledged that you have always and at once
known all things, that is to say, when you were a child, and at your
birth, and when you were growing up, and before you were born, and
before the heaven and earth existed, you knew all things if you always
know them; and I swear that you shall always continue to know all
things, if I am of the mind to make you.
But I hope that you will be of that mind, reverend Euthydemus, I said,
if you are really speaking the truth, and yet I a little doubt your
power to make good your words unless you have the help of your brother
Dionysodorus; then you may do it. Tell me now, both of you, for
although in the main I cannot doubt that I really do know all things,
when I am told so by men of your prodigious wisdom-how can I say that
I know such things, Euthydemus, as that the good are unjust; come, do
I know that or not?
Certainly, you know that.
What do I know?
That the good are not unjust.
Quite true, I said; and that I have always known; but the question is,
where did I learn that the good are unjust?
Nowhere, said Dionysodorus.
Then, I said, I do not know this.
You are ruining the argument, said Euthydemus to Dionysodorus; he will
be proved not to know, and then after all he will be knowing and not
knowing at the same time.
Dionysodorus blushed.
I turned to the other, and said, What do you think, Euthydemus? Does
not your omniscient brother appear to you to have made a mistake?
What, replied Dionysodorus in a moment; am I the brother of
Euthydemus?
Thereupon I said, Please not to interrupt, my good friend, or prevent
Euthydemus from proving to me that I know the good to be unjust; such
a lesson you might at least allow me to learn.
You are running away, Socrates, said Dionysodorus, and refusing to
answer.
No wonder, I said, for I am not a match for one of you, and a fortiori
I must run away from two. I am no Heracles; and even Heracles could
not fight against the Hydra, who was a she-Sophist, and had the wit to