198 Heredity and Social Progress 



doctrine of cell life and to use its conclusions 

 as premises in further discussion. 



It does not, however, seem to me that biolo- 

 gists are equally clear about the second 

 problem, that of growth as separate from that 

 of life. I have tried to state it in a simple 

 and distinct form. The duplication of parts 

 has its own laws independent of those of life, 

 and when they are dominant, simple multi- 

 cellular organisms result with the same vital 

 principles that unicellular organisms have, but 

 with a complexity that arises from the differ- 

 entiation of parts. 



The third problem has to do with the 

 equilibrium found between organisms with a 

 double growth and its effects in nerves and 

 consciousness. Emotions are the great factor 

 in the equilibrium and they act through reduc- 

 tions and regeneration, which gives a harmony 

 to parts that would otherwise be divergent in 

 their tendencies. Organs are, in faqt, organ- 

 isms reduced to harmony after many regenera- 

 tions, but at the same time so differentiated 

 that the action of each supplements that of the 

 others. 



