change either of cerebration or of mentation. Now it
is evident that if the mental processes were always the effects of
cerebral processes (Materialism), there could be no further question
with regard to Liberty and Necessity; while, if the mental processes are
the causes both of the cerebral processes and of one another
(Spiritualism), the question before us becomes raised to a higher level.
The causality in question being now regarded as purely mental, the will
is no longer regarded as a passive slave of the brain, and the only
thing to be considered is whether freedom is compatible with causation
of a purely mental kind. Now, at an earlier stage of our enquiry I have
argued that it is not; but this argument was based entirely upon
spiritualistic premises, or upon the assumption that the principle of
causality is everywhere external to, or independent of, the human
mind--under which assumption I cannot see that it makes much difference
whether the coercion comes from the brain alone, or from the whole
general system of things external to the human mind. And here it is that
I think the theory of Monism comes to the rescue.

For, if physical and mental processes are everywhere consubstantial, or
identical in kind, it can make no difference whether we regard their
sequences as objective or ejective, physical or spiritual. Hence, we are
free to regard all causation as of a character essentially psychical.
But, if so, it must be self-contained as psychical; it cannot be in any
way determined by anything from without, seeing that outside itself
there is nothing in the Universe. Now, if this is true of the
World-eject, it must also be true of the Man-eject, as well as of the
Man-subject, or Ego. If all causation is psychical, that portion of it
which belongs to, or is manifested by, my own personality is not laid
upon me by anything from without; it is merely the expression of my own
psychical activity, as this is taking place within the circumscribed
area of my own personality. And this activity is spontaneous, in the
sense that it is not coerced from without. All the sequences which that
activity displays within this region are self-determined, in the sense
that they are determined by the self, and not by any agency external to
it. The only influence which any external agency can here exert, is that
of insisting that bodily action--the physical outcome of my psychical
processes--shall be in accordance with the conditions i