in Plato's philosophy, is the sole reality. The object of sense
is unreal, and merely clogs and dims the soul's vision of the Ideas.
Matter is that which obstructs the free activity of the Idea.
Sense-objects hide the Idea from our view. Therefore the world of
sense is wholly evil. True virtue must consist in flying from the
world of sense, in retiring from the affairs of the world, and even
from the beauty of the senses, into the calm of philosophic
contemplation. And if this were all, philosophy, the knowledge of the
Ideas, would be the sole constituent of the _summum bonum_. But it is
possible to regard sense-objects in another light. They are, after
all, copies of the Ideas. They are therefore a manifestation and
revelation of the ideal world. Hence Plato is compelled by this
thought to allow a certain value to the world of sense, its affairs,
and its beauty.

The result of this inconsistency is, at any rate, that Plato remains
broad and human. He does not, on the one hand, preach a purely selfish
retirement into philosophy, or a narrow ascetic ideal. He does not, on
the other hand, adopt a low utilitarian view of life, allowing value
only to that which is "practical." He remains true to the Greek ideal
of life as a harmonious play of all the faculties, in which no one
part of man is over-developed at the expense of the others.

The result is that Plato's _summum bonum_ is not a single {223} end.
It is a compound consisting of four parts. First, and chief of all, is
the knowledge of the Ideas as they are in themselves, philosophy.
Secondly, the contemplation of the Ideas as they reveal themselves in
the world of sense, the love and appreciation of all that is
beautiful, ordered, and harmonious. Thirdly, the cultivation of the
special sciences and arts. And fourthly, indulgence in pure, refined,
and innocent pleasures of the senses, excluding, of course, whatever
is base and evil.

Plato had also a specific doctrine of virtue. As already stated, he
distinguished between philosophic and customary virtue, and attached
absolute value only to the former. He does not, however, deny a
relative value to customary virtue, inasmuch as it is a means towards
true virtue. Plato saw that man cannot rise at one bound to the
pinnacles of rational virtue. He must needs pass through the
preparatory stage of customary virtue. In the man in whom reason is
not yet awakened, good habits and customs must be implanted, in order
that,