nd 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 rational 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 experienced by the soul in its disembodied
state before birth. It must carefully be noted, however, that the word
knowledge is here used in the special and restricted sense of Plato.
Not everything that we should call knowledge is recollection. The
sensuous element in my perception that this paper is white is not
recollection, since, as being merely sensuous, it is not, in Plato's
opinion, to be called knowledge. Here, as elsewhere, he confines the
term {213} to rational knowledge, that is to say, knowledge of the
Ideas, though it is doubtful whether he is wholly consistent with
himself in the matter, especially in regard to mathematical knowledge.
It must also be noted that this doctrine has nothing in common with
the Oriental doctrine of the memory of our past lives upon the earth.
An example of this is found in the Buddhist Jatakas, where the Buddha
relates from memory many things that happened to him in the body in
his previous births. Plato's doctrine is quite different. It refers
onl