143 
Our author says that “mental phenomena are the subjective 
aspect of the functions of sensory and motor substrata ; that 
they are reducible to correlation with the activity of certain 
simple motor and sensory elements; that cerebral states 
include our volitions and emotions ; and that sensory centres 
are registers of sensations. - ” Again, he speaks of “ feelings 
and emotions with their physical substrata, and of the 
elementary substrata of mental phenomena. - ”* 
These, and other expressions in the paper, imply that the 
phusis and the psuche are different sides of one and the same 
substance ; or that the psuche is the aspect and the phusis the 
substratum. 
Bain says, “ the arguments for the two substances 
have lost their validity the one substance with two 
sets of properties, two sides, physical and mental 
appears to comply with ail the exigencies of the case.”f 
Huxley says, “ Matter and spirit are merely symbols by 
which we represent the forces which are supposed either to 
excite or bear up the thought. Matter must be reduced in 
thought to force ; and spirit is likewise force. So far they 
are identical. 
Tyndall supposes that there is “ but one substance, matter 
possessed of two sets of properties, of a physical and a 
spiritual side, making up a double-faced unity.” § 
According to Spencer, “ body is to be regarded as a modifi- 
cation of mind, and mind as a modification of body, both 
being different modes of one single substance.” || 
We do not know how far our author goes with these 
writers ; but when he says “ the cerebral cortex is the physical 
substratum, and the states of consciousness are the subjective 
aspect ” ; that as “ the cerebral cortex changes the con- 
sciousness changes correspondingly, the one being the sub- 
stratum, the other the aspect of it,” he appears to give up 
what dualists hold to be the key of their position ; and we do 
not think that, taking his stand where he does, on the relation 
of mind to brain, as aspect and substratum, or substratum and 
aspect, he could maintain [the position of the dualist against 
the authors referred to. 
But if the whole nerve organism be the elementary sub- 
strata of mental phenomena, and the mental phenomena be 
merely the subjective aspect of these substrata, and if we have a 
double-faced unity, having a physical and psychical side, every 
* Pages 111, 112, 122. 123, 124. 
t North British Review, p. 307. 
ij Gorman’s Psychology , p. 1 05. 
t Mind and Body , p. 196. 
§ Cook’s Lectures , p. 83. 
IF Page l2t. 
