COHESIVE POWER OF SOCIAL LIFE 253 



phases of growth are: growth, or development, of the 

 individual man; increase in population by his multi- 

 plication, or reproduction; and growth, or develop- 

 ment, of social units ; their division, or multiplication, 

 growth, cooperative union, etc. 



There is reasonable assurance that the triaxial sys- 

 tem of growth has practically reached its limits in 

 man. No notable modification in man's architectural 

 plan, in his physical dimensions, organic structure, or 

 vital power, is likely to take place, even in the very 

 remote future. It seems probable, however, that the 

 general average of attainment in the most characteris- 

 tic human traits will be much improved, and the dura- 

 tion of human life greatly increased, and with relative 

 rapidity. It is also quite possible that the impending 

 functional segregations of social life, with their spe- 

 cial trainings, common interests and mutual under- 

 standings, will tend more and more to minimize racial 

 and mental distinctions, and accentuate functional 

 types. 



The inherent limitations to man's further evolution, 

 as an individual organism, lie in the fact that no fur- 

 ther readjustments, or increments, of his chief vital 

 organs, such as have taken place in his more remote an- 

 cestors, are possible. Those changes have clearly 

 reached their logical conclusion. And as for his 

 purely muscular and nervous powers, so essential for 

 locomotion, internal circulation, and discriminating re- 

 sponse to external agents, further increase of power in 

 these directions is definitely prohibited by the limited 

 conductivity and tensile strength of living protoplasm 

 and its products; by its limited powers of assimilation 

 and response to physical agents; its limited ability to 



