nge introduced in the speculative standing of the subject. So long as
Matter and Mind, _x_ and _y_, are held to be antithetically opposed in
substance, so long must Materialism suppose that a connection of
_causality_ subsists between the two, such that the former substance is
_produced_ in some unaccountable way by the latter. But when Matter and
Mind, _x_ and _y_, are supposed to be identical in substance, the need for
any additional supposition as to a causal connection is excluded. But
unless we hold, what seems to me an uncalled-for opinion, that the
essential feature of Materialism consists in a postulation of a causal
connection between _x_ and _y_, it would appear that the only effect of
supposing _x_ and _y_ to be really but one substance _z_, must be that of
_strengthening_ the essential doctrine of Materialism--the doctrine,
namely, that conscious intellectual existence is _necessarily_ associated
with that form of existence which we know phenomenally as Matter and
Motion. If it is true that a "a moving molecule of inorganic matter does
not possess mind or consciousness, but it possesses a small piece of
Mind-stuff," then assuredly the central position of Materialism is shown to
be impregnable. For while it remains as true as ever that mind and
consciousness can only emerge when what we know phenomenally as "Matter
takes the complex form of a living brain," we have abolished the necessity
for assuming even a causal connection between the substance of what we know
phenomenally as Matter and the substance of what we know phenomenally as
Mind: we have found that, in the last resort, the phenomenal connection
between what we know as Matter and what we know as Mind is actually even
more intimate than a connection of causality; we have found that it is a
substantial identity.

To sum up this discussion. We have considered the bearing of modern
speculation on the doctrine of Materialism in three successive stages of
argument. First, we had to consider the bearing on Materialism of the
simple doctrine of Relativity. Here we saw that Materialism was only
affected to the extent of being compelled to allow that what we know as
Matter and Motion are not known as they are in themselves. But we also saw
that, as the inscrutable realities are uniformly translated into
consciousness as Matter and Motion, it still remains as true as ever that
_what we know_ as Matter and Motion may be the causes of what we know as
Mind. Even,