e, never fully developed till the time of Descartes.
And to say that Anaxagoras did not realize that mind is non-spatial is
merely to say that he lived before the time of Descartes. No doubt it
would follow from this that the incorporeality of mind is vaguely and
indistinctly conceived by Anaxagoras, that the antithesis between
matter and mind is not so sharply drawn by him as it is by us. But
still the antithesis is conceived, and therefore it is correct to say
that the Nous of Anaxagoras is an incorporeal principle. The whole
point of this introduction of the Nous into the philosophy of
Anaxagoras is because he could not explain the design and order of the
universe on a purely physical basis.

[Footnote 8: _Early Greek Philosophy_, chap. vi. Sec. 132.]

The next characteristic of Nous is that it is to be thought of as
essentially the ground of motion. It is because he cannot in any other
way explain purposive motion that Anaxagoras introduces mind into his
otherwise materialistic system. Mind plays the part of the moving
force which explains the world-process of unmixing. As the ground of
motion, the Nous is itself unmoved; for if there were any motion in it
we should have to seek for the ground of this motion in something else
outside it. That which is the cause of all motion, cannot itself be
moved. Next, the Nous is absolutely pure and unmixed with anything
else. It exists apart, by itself, wholly in itself, and for itself. In
contrast to matter, it is uncompounded and simple. It is this which
gives it omnipotence, complete power over everything, because there is
no mixture of matter in it to limit it, to clog and hinder its
activities. We moderns are {101} inclined to ask the question whether
the Nous is personal. Is it, for example, a personal being like the
God of the Christians? This is a question which it is almost
impossible to answer. Anaxagoras certainly never considered it.
According to Zeller, the Greeks had an imperfect and undeveloped
conception of personality. Even in Plato we find the same difficulty.
The antithesis between God as a personal and as an impersonal being,
is a wholly modern idea. No Greek ever discussed it.

To come now to the question of the activity of the Nous and its
function in the philosophy of Anaxagoras, we must note that it is
essentially a world-forming, and not a world-creating, intelligence.
The Nous and matter exist side by side from eternity. It does not
create matter, b