l causes. It is felt that
when a complete explanation of any given phenomenon has been furnished
in terms of these causes, there is no need to go further; the phenomenon
has been rendered intelligible on its mechanical side, and therefore it
is felt that we have no reason to suppose that it presents a mental
side--any supplementary causation of a mental kind being regarded as
superfluous. Even writers who expressly repudiate this reasoning prove
themselves to be habitually under its influence; for we constantly find
that such writers, after conceding the mechanical explanations as far as
these have been _proved_, take their stand upon the more intricate
phenomena of Nature where, as yet, the mechanical explanations are not
forthcoming. Whether it be at the origin of life, the origin of
sentiency, of instinct, of rationality, of morality, or of religion,
these writers habitually argue that here, at least, the purely
mechanical interpretations fail; and that here, consequently, there is
still room left for a psychical interpretation. Of course the pleading
for theism thus supplied is seen by others to be of an extremely feeble
quality; for while, on the one hand, it rests only upon ignorance of
natural causation (as distinguished from any knowledge of super-natural
causation), on the other hand, abundant historical analogies are
available to show that it is only a question of time when pleading of
this kind will become more and more restricted in its subject-matter,
till eventually it be altogether silenced. But the pleading which Monism
is here able to supply can never be silenced.

For, according to Monism, all matter in motion is mind; and, therefore,
matter in motion is merely the objective revelation, _to_ us and _for_
us, of that which in its subjective aspect--or in its ultimate
reality--is mind. Just as the operations of my friend's mind can only be
revealed to me through the mechanical operations of his body, so it may
very well be that the operations of the Supreme Mind (supposing such to
exist) can only be revealed to me through the mechanical operations of
Nature. The only difference between the two cases is that while I am
able, in the case of my friend's mind, to elicit responses of mechanical
movement having a definite and intended relation to the operations of my
own mind, similarly expressed to him; such is not the case with Nature.
With the friend-eject I am able to _converse_; but not so with the
world-