ON THE REALITY OF THE SELF. 199 
the shadow of those material movements in consciousness. 
Thus sensation becomes the effect of which molecular 
agitation in the nerves is the cause. This is usually called 
Materialism. But it is in reality useless to tell us not to ask 
questions which science stigmatises as impossible and absurd. 
Impossible questions will nevertheless be asked, and science 
and philosophy will appear to have failed, unless some sort 
of answer 1s forthcoming. If then we turn to the more 
definite answer of Materialism, we have to try to imagine 
how mental states can be the products of movement in 
material molecules, just as a carpet is the product of the 
loom. Is Thought a secretion of the brain, just as 
perspiration is the secretion of sudatory glands, and tears 
the secretion of the tear-ducts? But the secretory product 
of the brain is the fluid found in certain of its cavities, and 
this fluid is no more like a mental process than the 
deficiency in gastric juice is like a feeling of indigestion, 
And it we put “the theory in a more refined form and say 
that nerve-commotion is the product of the molecular activity 
of the brain, still a neural shock or nerve-commotion is not 
what we are conscious of in sensation. The language of the 
Materialists appears thus almost meaningless, as an explana- 
tion of all those mental processes of which we are intuitively 
aware. And so some of these scientific psychologists, as, 
e.g.. Mr. G. H. Lewes and Mr. Bain, seek to amend their 
theory somewhat, and speak of equivalence and identity, 
rather than of causation and production, The mind and 
brain stand to one another, they tell us, as convex and 
concave sides of the same arc. The two aspects are of one 
identical thing, Viewed from one position the arc is concave, 
from. another it is convex: and so viewed from different 
standpoints the same phenomenon is now a material motion, 
and now a conscious process of the mind. We ought to 
speak ef a “ double-faced unity” showing itself both as 
mental and as corporeal, having one aspect which is spiritual 
and another which is material. This is plausible at all 
events; nor is there any way of either proving or disproving 
the theory, unless we have grounds for saying that the mind 
has a reality of its own apart from the material embodiment, 
and that we have evidence to show it to be within its own 
sphere distinct and supreme. Can we bring any arguments 
to bear upon this reality of mind, separate and separable from 
the nervous mechanism? I think we can, and these 
arguments shall be drawn from different sources, and 
illustrate different aspects of the question. 
