INTELLIGENCE, POWER, 



of the thinking brain is not comparable to the survival 

 value of the thinking brain of man who has created the 

 machine age, developed science, art, agriculture, invented 

 methods of communication, and devised educational sys- 

 tems, philosophies, and government. 



The mind of man has its greatest survival value in the 

 temperate zone, especially in that part of the temperate 

 zone where there is an abundance of coal, oil, iron, farming 

 and grazing land, where storms and a change of seasons 

 invigorate man and endow him with greater muscular, 

 emotional, and mental energy. In this zone of change and 

 storm we find not only the highest development of civilized 

 man but also the highest incidence of diseases peculiar to 

 civilized man, for the genesis of each depends upon a large 

 brain, a large thyroid gland, a large heart and volume of 

 blood, a large celiac ganglion and plexus and adrenal- 

 sympathetic system. As stated previously, we also find 

 particularly effective for both civilized man and his diseases 

 the application of the law of mutation, which, on the one 

 hand, produces scholars and philanthropists and, on the 

 other hand, mental defectives and criminals. 



From these considerations it is clear that neither the 

 Eskimo nor the African native nor wild animals could 

 achieve civilization, nor could they acquire any more easily 

 the diseases peculiar to civilized man. It is clear, also, that 

 civilized man is approaching the ceiling of safe further 

 development of his energy system. 



We recognize the fact that we have not given final proof 

 of any one of the applications of the several biological laws 

 that we have evoked in our attempt to define the mechan- 

 ism of civilized man. Even the principle of evolution cannot 

 be proved, though it is accepted. Nevertheless, Darwin's 

 principle of struggle and survival, Haeckel's principle of 

 ontogeny and phylogeny, De Vries' principle of mutation, 

 Berthelot's law, which we have applied to explain the 

 limitations of temperature and heatstroke among warm- 



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