The Timaeus of Plato

20 INTRODUCTION.
of ideas, (4) a theory of the relation of soul, universal and
particular,
to the universe. The
latent in the earlier Platonism :
answer to these problems may be
but Plato has not yet realised the
possibilities of his theory. By the time he has done this, we find
most important modifications effected in it. Still they are but
modifications: Plato's theory remains the theory of ideas, and
none other, to the end.
The Par- 19. The severe and searching criticism to which Plato submenides.
ec j ts his own theory is begun in the Parmenides. This remarkable
dialogue falls into two divisions of very unequal length. In the
first part Parmenides criticises the earlier form of the theory of
ideas ;
in the second he applies himself to the investigation of the
One, and of the consequences which ensue from the assumption
either of its existence or of its non-existence. The discussion of
the ideal theory in the first part turns upon
the relation between
idea and particulars. Sokrates offers several alternative suggestions
as to the nature of this relation, all of which Parmenides shows to
The purport of his
be subject to the same or similar objections.
criticisms maybe summed up as follows: (i) if particulars participate
in the idea, each particular must contain either the whole
idea or a part of it ;
in the one case the idea exists as a number of
separate wholes, in the other it is split up into fractions ; and,
whichever alternative we accept, the unity of the idea is equally
sacrificed :
(2) we have the difficulty known as the rpiVos av-
Opwiros
if all things which are like one another are like by virtue
of participation in the same idea, then, since idea and particulars
resemble each other, they must do so by virtue of resembling
some higher idea which comprehends both idea and particulars,
and so forth ets aTreipov if :
(3) the ideas are absolute substantial
existences, there can be no relation between them and the world
of particulars
: ideas are related to ideas, particulars to particulars ;
intelligences which apprehend ideas cannot apprehend particulars,
and vice versa. It may be observed that the second objection is
not aimed at the proposition that particulars resemble one another
because they resemble the
same idea, but against the hypothesis
that because particulars in a given group resemble each other it is
necessary to assume an idea corresponding to that group.
Sokrates is unable to parry these attacks upon his theory, but
in the second part of the dialogue Plato already prepares a way of
escape.
In the eight hypotheses comprised in this section of the
dialogue Parmenides examines TO
v, conceived in several different