54 Origin and Primal Condition of Man. 



of form, etc., in each individual,] innate internal powers to 

 the full as mysterious must anyhow be accepted, whether 

 they act in specific origination [origin or species] or not. 

 Besides all this, we have seen that it is probable that the 

 action of this innate power is stimulated, evoked and de- 

 termined by external conditions, and also that the same 

 external conditions in the shape of "natural selection, " 

 play an important part in the evolutionary process ; and, 

 finally, it has been affirmed that the view here advocated, 

 while it is supported by the facts on which Darwinism 

 rests, is not open to the objections and difficulties which op- 

 pose themselves to it as the sole agent in genesis of species. 



The most severe opposition to the theory of evolution of 

 species as applied to man is the psychical. The mind of 

 man is considered so utterly and radically unlike that of 

 any other animal as to forbid the possibility of his descent 

 from animals. Maudsley , however, has carefully investigated 

 the physiology and pathology of mind, and in his work on 

 that subject, he shows the similarity between the entire 

 nervous system of man and animals both in structure and 

 in use ; rising from the nerves the spine is considered as 

 the seat of reflex action and of coordinated motions such 

 as are performed unconsciously and as the result of 

 habit. A step higher is placed the sensory-motor system 

 in the lower part of the skull, and in the ganglia contain- 

 ing the organs of special senses, including what are called 

 the five senses, which also may to an extent be exercised 

 unconsciously and without volition, both in man and ani- 

 mal. Rising to the supreme nervous centre, the hemi- 

 spherical lobes of the brain, he illustrates at great length their 

 mode of action among all vertebrates ; and on the other 

 hand, their pathological action and retrograde metamor- 

 phosis in insanity, and does not hesitate to maintain that 

 the only difference between the mind of man and that of 

 brutes is one of degree and not of kind. In attempting 



