MENTAL AND SOCIAL EVOLUTION 



WHILE the principle of evolution is quite 

 apparent in the physical life of organ- 

 isms, and of man. it is more difficult to 

 perceive it in the psychical life. With 

 man there is a higher degree of mentality than in any 

 other organism, which must be considered as a function 

 of the physical. This gives him a much wider and more 

 complex environment, with which he is in correspon- 

 dence. But, as there is a comparative anatomy and 

 physiology, so there is a comparative mentality, in the 

 organic kingdom. Especially is this so in the animal 

 class. It will be seen that the increase of mentality in 

 the animal class is parallel with the development of a 

 specialized structure ; and while it seems essential to 

 the study of the evolution of organisms, to divide the 

 psychical from the physical, yet in reality they are one, 

 genetically. They are distinctive only in their mani- 

 festations. 



DISTINCTIVE FEATURES OF LIFE. Living tissue, wher- 

 ever found, from the lowest to the highest organ- 

 ism, has a certain peculiar movement, which character- 

 izes it, as different from inorganic matter. This move- 

 ment is its correspondence with inorganic matter. 

 From the latter, it is constantly drawing, and appro- 

 priating certain elements. When this process, or 

 movement ceases in the living tissue, It becomes at 

 once, only inorganic matter. It seems therefore to be 

 a medium only for transferring inorganic matter into 

 living matter, and back again to its source. An organ- 



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