Here we have, first of all, an unmistakable attack made by the youthful
Socrates on the paradoxes of Zeno. He perfectly understands their drift,
and Zeno himself is supposed to admit this. But they appear to him, as
he says in the Philebus also, to be rather truisms than paradoxes. For
every one must acknowledge the obvious fact, that the body being one
has many members, and that, in a thousand ways, the like partakes of
the unlike, the many of the one. The real difficulty begins with the
relations of ideas in themselves, whether of the one and many, or of
any other ideas, to one another and to the mind. But this was a problem
which the Eleatic philosophers had never considered; their thoughts had
not gone beyond the contradictions of matter, motion, space, and the
like.
It was no wonder that Parmenides and Zeno should hear the novel
speculations of Socrates with mixed feelings of admiration and
displeasure. He was going out of the received circle of disputation into
a region in which they could hardly follow him. From the crude idea of
Being in the abstract, he was about to proceed to universals or general
notions. There is no contradiction in material things partaking of the
ideas of one and many; neither is there any contradiction in the ideas
of one and many, like and unlike, in themselves. But the contradiction
arises when we attempt to conceive ideas in their connexion, or to
ascertain their relation to phenomena. Still he affirms the existence of
such ideas; and this is the position which is now in turn submitted to
the criticisms of Parmenides.
To appreciate truly the character of these criticisms, we must remember
the place held by Parmenides in the history of Greek philosophy. He
is the founder of idealism, and also of dialectic, or, in modern
phraseology, of metaphysics and logic (Theaet., Soph.). Like Plato,
he is struggling after something wider and deeper than satisfied the
contemporary Pythagoreans. And Plato with a true instinct recognizes
him as his spiritual father, whom he 'revered and honoured more than all
other philosophers together.' He may be supposed to have thought more
than he said, or was able to express. And, although he could not, as
a matter of fact, have criticized the ideas of Plato without an
anachronism, the criticism is appropriately placed in the mouth of the
founder of the ideal philosophy.