On The Soul   

uses language like that of the comic dramatist Philippus, who accounts

for the movements that Daedalus imparted to his wooden Aphrodite by

saying that he poured quicksilver into it; similarly Democritus says

that the spherical atoms which according to him constitute soul, owing

to their own ceaseless movements draw the whole body after them and so

produce its movements. We must urge the question whether it is these

very same atoms which produce rest also-how they could do so, it is

difficult and even impossible to say. And, in general, we may object

that it is not in this way that the soul appears to originate movement

in animals-it is through intention or process of thinking.

It is in the same fashion that the Timaeus also tries to give a

physical account of how the soul moves its body; the soul, it is there

said, is in movement, and so owing to their mutual implication moves

the body also. After compounding the soul-substance out of the

elements and dividing it in accordance with the harmonic numbers, in

order that it may possess a connate sensibility for 'harmony' and that

the whole may move in movements well attuned, the Demiurge bent the

straight line into a circle; this single circle he divided into two

circles united at two common points; one of these he subdivided into

seven circles. All this implies that the movements of the soul are

identified with the local movements of the heavens.

Now, in the first place, it is a mistake to say that the soul is a

spatial magnitude. It is evident that Plato means the soul of the

whole to be like the sort of soul which is called mind not like the

sensitive or the desiderative soul, for the movements of neither of

these are circular. Now mind is one and continuous in the sense in

which the process of thinking is so, and thinking is identical with

the thoughts which are its parts; these have a serial unity like

that of number, not a unity like that of a spatial magnitude. Hence

mind cannot have that kind of unity either; mind is either without

parts or is continuous in some other way than that which characterizes

a spatial magnitude. How, indeed, if it were a spatial magnitude,