45 



actions of the cerebrum and cerebellum upon the medulla 

 oblongata and structures it presides over." 1 



In a word, psychical phenomena come within the scope of 

 Spencer's formula of evolution enunciated at the beginning of 

 our exposition. "Nerve being supposed to have the molecular 

 structure and properties which, at the beginning of this work 

 we found such numerous reasons for assigning to it, we have 

 inferred from established laws of motion that the molecular 

 change wrought in it by every discharge it conveys leaves it 

 in a state for conveying a subsequent like discharge with less 

 resistance. This being the universal law of nervous action, 

 explains the universal law of intelligence." 2 



It is thus seen how closely dependent, according to Spencer, 

 are the phenomena of consciousness upon physiological states 

 of the brain and nervous system. In the following it will be 

 seen how this works out in Spencer's system. In these state- 

 ments it would appear that the foundation for psychological 

 association is laid in physiological conditions. As we have 

 already seen, such a situation has been suggested by J. S. Mill 

 in the words: "When one thought seems to call up another by 

 association, it is not really a thought which recalls a thought; 

 the association did not exist between the two thoughts, but 

 between the two states of the brain or nerves which preceded 

 the thoughts; one of those states recalls the other, each being 

 attended, in its passage, by the particular mental state which 

 is consequent upon it." 3 Although Mill was not altogether 

 prepared to accept such a theory on account of the scant "data 

 as physiology at present affords", 4 still, it is apparent that he 

 leaves room in his definition of psychology for its inclusion, in 

 case further physiological data were forthcoming. It does not 

 appear, however, that Spencer has proceeded as cautiously 

 as did Mill, which may be seen in the following. Supplementing 

 his description of the rise of sensations, 5 Spencer informs us 

 that "the method by which simple sensations, and the re- 

 lations among them, are compounded into states of definite 

 consciousness, is essentially analogous to the method by which 

 primitive units of feeling are compounded into sensations. * 

 The next higher stage of mental composition shows us this 



1 O.C. 245-6-7. 



2 O.C. 268, which, we should like to point out again, is inconsistent 

 with Spencer's statement that mental states cannot be conceived as forms 

 of matter and motion, and do not, therefore, necessarily conform to the same 

 laws of redistribution; that is, if they do, it is mere coincidence, and one 

 does not explain the other. 



3 J. S. Mill, "Logic", VI, 4 2. 



4 Ibid. 



That is, as a result of physical molecular change, as above indicated. 



