On The Soul
appear to be certain animals which stationary, and yet local
movement is the only one, so it seems, which the soul originates in
animals. And (2) the same object-on holds against all those who
construct mind and the perceptive faculty out of the elements; for
it appears that plants live, and yet are not endowed with locomotion
or perception, while a large number of animals are without discourse
of reason. Even if these points were waived and mind admitted to be
a part of the soul (and so too the perceptive faculty), still, even
so, there would be kinds and parts of soul of which they had failed to
give any account.
The same objection lies against the view expressed in the 'Orphic'
poems: there it is said that the soul comes in from the whole when
breathing takes place, being borne in upon the winds. Now this
cannot take place in the case of plants, nor indeed in the case of
certain classes of animal, for not all classes of animal breathe. This
fact has escaped the notice of the holders of this view.
If we must construct the soul out of the elements, there is no
necessity to suppose that all the elements enter into its
construction; one element in each pair of contraries will suffice to
enable it to know both that element itself and its contrary. By
means of the straight line we know both itself and the curved-the
carpenter's rule enables us to test both-but what is curved does not
enable us to distinguish either itself or the straight. Certain
thinkers say that soul is intermingled in the whole universe, and it
is perhaps for that reason that Thales came to the opinion that all
things are full of gods. This presents some difficulties: Why does the
soul when it resides in air or fire not form an animal, while it
does so when it resides in mixtures of the elements, and that although
it is held to be of higher quality when contained in the former?
(One might add the question, why the soul in air is maintained to be
higher and more immortal than that in animals.) Both possible ways
of replying to the former question lead to absurdity or paradox; for