MENTAL AND SOCIAL EVOLUTION 151 



in man, which distinguish him from the lower animals, 

 he would be little liable to change in bodily modifica- 

 tions through natural selection, or any other means. 

 That is, man through his mental faculties is enabled 

 to keep in harmony with the changing universe, with 

 an unchanged body. Following this essay, by Wallace, 

 or perhaps before, or simultaneously, many opponents 

 of the evolution theory, took heart, and began to assert 

 that the evolution of reason in man gave him control 

 of his own development, and as to him, natural selec- 

 tion did not apply. There is no doubt that man has 

 great power of adapting his habits to new conditions 

 in life. His inventive genius enables him to make tools 

 and implements to aid him in his correspondence with 

 a more complex environment, far beyond the power of 

 the lower animals. These inventions enable him to 

 get into touch with more productive sources of natural 

 law, but not to change those laws for his own benefit. 

 This increased mental power comes to him only, as his 

 nervous structure increases, so as to bear a larger ratio 

 to his total body, or at least by largely increasing the 

 complexity of his nervous system. While this can be 

 done, perhaps, without very greatly changing his out- 

 ward bodily form, yet it is a change of bodily form 

 internally, and this change is, undoubtedly, continually 

 modifying the whole bodily structure. By comparing 

 the head, and facial expression, of an intellectual white 

 man, with a red savage Indian, one can readily com- 

 prehend this fact. Every change, in the mental capac- 

 ity, is imaged in the external physical marks of the 

 body. 



Man can never be entirely freed from the control 

 of biological evolution by reason of an increase of his 

 psychology, which means his correspondence with his 



