space. He bisects it, and bends the two halves into an inner
and an outer circle, these circles being destined to become
the spheres of the planets and the stars respectively. He
takes matter and binds it into the four elements, and these
elements he builds into the empty framework of the World-
Soul. When this is done, the creation of the universe is
complete. The rest of the “Timaeus” is occupied with the
details of Plato’s ideas of astronomy and physical {211}
science. These are mostly worthless and tedious, and we
need not pursue them here. But we may mention that
Plato, of course, regarded the earth as the centre of the
world. The stars, which are divine beings, revolve around
it. They necessarily move in circles, because the circle is the
perfect figure. The stars, being divine, are governed solely
by reason, and their movement must therefore be circular,
because a circular motion is the motion of reason.
The above account of the origin of the world is merely myth,
and Plato knows that it is myth. What he apparently did
believe in, however, was the existence of the World-Soul,
and a few words upon this subject are necessary. The soul,
in Plato’s system, is the mediator between the world of
Ideas and the world of sense. Like the former, it is incorpo-
real and immortal. Like the latter, it occupies space. Plato
thought that there must be a soul in the world to account
for the rational behaviour of things, and to explain motion.
The reason which governs and directs the world dwells in
the World-Soul. And the World-Soul is the cause of motion
in the outer universe, just as the human soul is the cause
of the motions of the human body. The cosmos is a living
being.
(b) The Doctrine of the Human Soul.The human soul is similar in kind to the World-Soul. It is
the cause of the body’s movements, and in it the human
reason dwells. It has affinities both with the world of Ideas
and the world of sense. It is divided into two parts, of
which one part is again subdivided into two. The highest
part is reason, which is {212} that part of the soul which
apprehends the Ideas. It is simple and indivisible. Now all
destruction of things means the sundering of their parts.
But the rational part of the soul, being simple, has no parts.
Therefore it is indestructible and immortal. The irrational
part of the soul is mortal, and is subdivided into a noble
and an ignoble half. To the noble half belong courage,
love of honour, and in general the nobler emotions. To the
ignoble portion belong the sensuous appetites. The noble
half has a certain affinity with reason, in that it has an
instinct for what is noble and great. Nevertheless, this is
mere instinct, and is not rational. The seat of reason is
the head, of the noble half of the lower soul, the breast,
of the ignoble half, the lower part of the body. Man alone
possesses the three parts of the soul. Animals possess the
two lower parts, plants only the appetitive soul. What
distinguishes man from the lower orders of creation is thus
that he alone possesses reason.Plato connects the doctrine of the immortality of the ratio-
nal soul with the theory of Ideas by means of the doctrines
of recollection and transmigration. According to the former
doctrine, all knowledge is recollection of what was experi-
enced by the soul in its disembodied state before birth. It
must carefully be noted, however, that the word knowledge