Devolution 127 



and organs which causes them to respond 

 more fully to the environing conditions. Life 

 is a rhythm between favorable and unfavor- 

 able contact, and each higher form of life is 

 an expression, in some complex way, of the 

 primary rhythm on which all life depends. 



SUMMARY 



1. Growth is not a steady process. Periods of increas- 

 ing specialization are followed by others of despecialization 

 and simplification. Regeneration follows disruption if 

 access to material is not prevented. 



2. When growth starts from an undifferentiated cell, new 

 cells are added alternately on each side, so that a balance 

 is maintained. If growth stops on one side, it ceases on the 

 other. When one side is cut back or ruptured, the other 

 must be reduced to a like degree before fresh growth 

 begins. 



3. This cutting back is devolution. Equilibriums are 

 obtained by backward movements. Sudden changes are 

 made by subtraction, not by addition. 



4. The agent of devolution is emotion. It arises when 

 there is a lack of balance between two related parts and pro- 

 duces shocks until despecialization restores the equilibrium. 

 Tendencies toward an equilibrium are tendencies toward 

 simplification, which remain active until the complexity and 

 differentiation of growth disappear. Then fresh growth re- 

 stores all, or even more, than was lost. 



5 . Emotion may thus be the cause of cures. Many dis- 



