harge of introducing a
theism altogether inconsistent with his philosophy, but it brings us
back to the old difficulty. For in this case, the existence of things
must be explained by means of the Idea of the Good. But this Idea is
just as impotent as the other Ideas.

In this connection, too, the dualism of Plato's system becomes
evident. If everything is grounded in the one ultimate reality, the
Ideas, then the entire universe must be clasped together in a system,
all parts of which flow out of the Ideas. If there exists in the
universe anything which stands aloof from this system, remains
isolated, and cannot be reduced to a manifestation of the Ideas, then
the philosophy has failed to explain the world, and we have before us
a confessed dualism. Now not only has Plato to drag in God for the
explanation of things, he has also to drag in matter. God takes matter
and forms it into copies of the Ideas. But what is this matter, and
where does it spring from? Clearly, if the sole reality is the Ideas,
matter, like all else, must be grounded in the Ideas. But this is not
the case in Plato's system. Matter appears as a principle quite
independent of the Ideas. As its being is self-derived and original,
it must be itself a substance. But this is just what Plato denies,
calling it absolute {239} not-being. Yet since it has not its source
in the Ideas or in anything outside itself, we must say that though
Plato calls it absolute not-being, it is in fact an absolute being.
The Ideas and matter stand face to face in Plato's system neither
derived from the other, equally ultimate co-ordinate, absolute
realities. This is sheer dualism.

The source of this dualism is to be found in the absolute separation
which Plato makes between sense and reason. He places the world of
sense on one side, the world of reason on the other, as things
radically different and opposed. Hence it is impossible for him ever
to bridge the gulf that he has himself created between them. We may
expect the dualism of a philosophy which builds upon such premises to
break out at numerous points in the system. And so indeed it does. It
exhibits itself as the dualism of Ideas and matter, of the sense-world
and the thought-world, of body and soul. Not, of course, that it is
not quite right to recognize the distinction between sense and reason.
Any genuine philosophy must recognize that. And no doubt too it is
right to place truth and reality on the side of reason