Heredity in its Relation to the Nervous System. 4.5 



and mental, of man, to think of our futile microscopes and our 

 infantile chemical analyses, and so to gather some idea of the 

 vanity of attempting to pry into the how of the inheritance of 

 either inborn or acquired traits. The law exists, and from a 

 physiological standpoint argues in favour of determinism. But 

 psychology must also be considered, and hence the influence of 

 the nervous system. If the mind is merely a physical outcome 

 of the brain, then psychological and physiological phenomena 

 cannot be distinguished, but the theory of the soul's existence 

 is an important factor here. Luys and Maudsley both hold that 

 the physical operations of the brain constitute intellectual and 

 moral life, and that by means of these, it feels, remembers, and 

 re-acts. This materialistic doctrine, which asserts the identity 

 of brain and thought, sets aside all idea of free will. It 

 maintains that " The organism is the man himself," that 

 " intelligence is the result of organic phenomena," that 

 "thought is only a function of the nervous centres." But is 

 this so ? Internal phenomena can only be perceived by one 

 faculty — consciousness, and Maudsley himself admits that they 

 are incapable of experimental demonstration. The moral and 

 physical are not identical, for the mind, conscious of motion, is 

 also conscious of itself. It is an " ego " and cannot be produced 

 by a material organ. The brain is the organ of thought, as the 

 eye is the organ of vision, and as perfect vision depends up<<n a 

 perfect eye, so perfect thought depends upon a perfect brain. 

 Now the nervous system has certain leanings in a definite 

 direction, and what that direction is, is determined by influence, 

 which even affected remote ancestors. But it is in youth easily 

 moulded. Hence the great problem of Education for habit 

 becomes second nature. 



Psychologically ''apperception" is defined as a psychical 

 activity by which individual perceptions are brought into 

 relation to our previous intellectual and emotional life, 

 assimilated with it, and raised to greater clearness and 

 significance. It thus indicates the intimate relationship between 

 Heredity and the Nervous System, and may be considered the 



