MENTAL LIFE 



the product of force. Monism escapes the one-sidedness 

 of both systems, and, as hylozoism, refuses to separate 

 the two attributes of substance, space-fiUing matter and 

 active energy. This applies to mental life just as to any 

 other natural process; our mental forces or phronetic 

 energies are just as much bound up with the neuroplasm, 

 the living plasm of the neurona in the cortex, as the 

 mechanical energy of our muscles is with the contractile 

 myoplasm, the living muscular substance. 



In the exhaustive study of consciousness which I gave 

 in the tenth chapter of the Riddle I sought to show that 

 this enigmatic function — the central mystery of psychol- 

 ogy — is not a transcendental problem, but a natural 

 phenomenon, subject to the law of substance, as much as 

 any other psychic power. The child's consciousness only 

 develops long after its first year, and grows as gradually 

 as any other psychic function; like these, it is bound up 

 with the normal anatomic and chemical condition of its 

 organs, the phroneta in the cortex. Consciousness 

 develops originally out of unconscious functions (as 

 an "inner view," or mirroring, of the action of the 

 phronema) ; and at any time an unconscious process in 

 the cortex may come within the sphere of consciousness 

 by having the attention directed to it. On the other 

 hand, conscious actions, which need a good deal of 

 attention when they are first learned (such as playing 

 the piano), may become unconscious through frequent 

 repetition and practice. The fact that chemical energy 

 is converted in the phronetal cells during any of these 

 actions is proved by the fatigue and exhaustion which 

 prolonged mental work causes in the brain, just as 

 mechanical work does in the muscles. Fresh matter has 

 to be supplied by the food before the mental work can 

 be continued. Moreover, it is well known that various 

 drinks have a considerable influence on consciousness 

 (coffee and tea, beer and wine); and the temporary 



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