126 Heredity and Social Progress 



that life is a series of ferments. 1 Growth is 

 obtained by one series of ferments, and a cut- 

 ting back or dwarfing results from another. 

 The process of growth is thus reversible. An 

 organism grows under favorable contact and 

 draws back or shrivels under adverse con- 

 tact. If this is true of the chemical ferments 

 in cells it confirms my contention that ad- 

 verse contact incites devolutional forces among 

 the cells of an organism, and reduces the 

 parts they affect to a greater simplicity. 

 Every adverse contact with the environment 

 brings a recoil, and the emotion is the psy- 

 chic expression of its physical effects. Growth 

 begins anew when the adverse contact ceases. 

 Beings do not adjust themselves to an envi- 

 ronment and afterward remain stationary until 

 a new adjustment is made possible by changed 

 conditions. They continually press forward 

 toward new adjustments and then are set 

 back by adverse contact. These constant for- 

 ward and backward movements make regen- 

 eration possible and give a plasticity to tissues 



1 Sec an article on "The Newest Concepts of Life 1 ' by Carl 

 Snyder, in Harper's Magazine, November, 1902. 



