there is no rational account are not knowable-such was the singular
expression which he used-and that things which have a reason or
explanation are knowable.
Soc. Excellent; but then, how did he distinguish between things
which are and are not "knowable"? I wish that you would repeat to me
what he said, and then I shall know whether you and I have heard the
Theaet. I do not know whether I can recall it; but if another person
would tell me, I think that I could follow him.
Soc. Let me give you, then, a dream in return for a dream:-Methought
that I too had a dream, and I heard in my dream that the primeval
letters or elements out of which you and I and all other things are
compounded, have no reason or explanation; you can only name them, but
no predicate can be either affirmed or denied of them, for in the
one case existence, in the other non-existence is already implied,
neither of which must be added, if you mean to speak of this or that
thing by itself alone. It should not be called itself, or that, or
each, or alone, or this, or the like; for these go about everywhere
and are applied to all things, but are distinct from them; whereas, if
the first elements could be described, and had a definition of their
own, they would be spoken of apart from all else. But none of these
primeval elements can be defined; they can only be named, for they
have nothing but a name, and the things which are compounded of
them, as they are complex, are expressed by a combination of names,
for the combination of names is the essence of a definition. Thus,
then, the elements or letters are only objects of perception, and
cannot be defined or known; but the syllables or combinations of
them are known and expressed, and are apprehended by true opinion.
When, therefore, any one forms the true opinion of anything without
rational explanation, you may say that his mind is truly exercised,
but has no knowledge; for he who cannot give and receive a reason
for a thing, has no knowledge of that thing; but when he adds rational
explanation, then, he is perfected in knowledge and may be all that
I have been denying of him. Was that the form in which the dream
appeared to you?
Soc. And you allow and maintain that true opinion, combined with
definition or rational explanation, is knowledge?
Soc. Then may we assume, Theaetetus, that to-day, and in this casual
manner, we have found a truth which in former times many wise men have
grown old and have not found?
Theaet. At any rate, Socrates, I am satisfied with the present
Soc. Which is probably correct-for how can there be knowledge
apart from definition and true opinion? And yet there is one point
in what has been said which does not quite satisfy me.
Theaet. What was it?
Soc. What might seem to be the most ingenious notion of all:-That
the elements or letters are unknown, but the combination or
Theaet. And was that wrong?
Soc. We shall soon know; for we have as hostages the instances which
the author of the argument himself used.
Theaet. What hostages?
Soc. The letters, which are the clements; and the syllables, which
are the combinations;-he reasoned, did he not, from the letters of the
Theaet. Yes; he did.
Soc. Let us take them and put them to the test, or rather, test
ourselves:-What was the way in which we learned letters? and, first of
all, are we right in saying that syllables have a definition, but that
letters have no definition?
Theaet. I think so.