The Metajyhysics of a Naturalist 
25 
what revolting statement^ but the method of escape from it 
is by the recognition of the measure of truth in it. It is possible 
that bile might be secreted without a liver and entirely probable 
that thought can exist without a brain; but in the case of man, the 
organ we call a brain is the evidence appealing to the senses of 
the existence of those marvelously complicated acts which make 
up the soul-life in man. When we view an object in a glass, at the 
same time looking at the object itself, we need not be surprised 
that the movements of the image are synchronous with those of 
the object nor invent theories to account for the explanation 
of the conformity observed. Still less do we seek to show that 
movements of the image in the glass cause those of the object itself. 
And yet the common attempt to indicate how the brain produces 
thought is not more absurd than the suppositions mentioned. 
The theories respecting the relation between the soul and body 
are, of course, much influenced by the view entertained as to the 
intrinsic nature of the two subjects of thought. For those who 
regard body and soul as distinct and disparate entities, a diffi- 
culty at once arises in accounting for the constant connection 
between the brain and thought. We are told that the nervous 
processes produce the phenomena of consciousness which we call 
sensation, feeling, perception, impulse and will. Still we are 
assured that these ‘^psychical activities’^ are the expression of 
the life of a peculiar being which is immaterial and consequently 
not in space and is a metaphysical unit and so indivisible that it 
must be in only one place at a time, and other interesting things 
all equally undemonstrable and unintelligible. In some way the 
material body acts upon the immaterial soul to cause the latter 
to act as it does in the processes of thought and volition and 
feeling. All physical analogies here seem to break down. If we 
attempt to employ the analogy of the transfer of a physical force 
from one mass of matter to another we have the difficulty con- 
fronting us that it is insisted that the soul is as unlike as possible 
to the matter of the body from which the force is supposed to 
emanate. But by all analogy likeness is a necessary condition 
for the transfer of force from one body to another and it is thought 
by some logicians that the predicate of likeness is really only the 
statement in another way of the fact that the two objects com- 
pared are capable of reacting on each other. Again in the view 
held by the advanced school of physicists, the passage of a force 
