136 THE EVOLUTION OF MAN 



always cut across organic criteria, it is certainly out of its range 

 when it comes to institutional development. If we read that 

 cannibalism or feudalism has perished by "a sort of natural 

 selection," the very qualification in the phrase indicates that 

 the user of it is merely employing an analogy. We are, I 

 repeat, upon another plane of evolution where the processes 

 and survival-values are somewhat altered from those existing 

 in nature. The attempt to carry natural selection over to the 

 new plane is wholly unproductive. 



It is understood, then, that evolution in the societal range 

 is of a different kind, quality, brand, or variety from that 

 operating in nature. Societal adjustments, we go on to infer, 

 are probably produced by the operation of factors present in 

 the organic field, though these factors must needs be somewhat 

 metamorphosed in their manifestations in the societal range. 

 To one who has in mind such considerations as the foregoing, 

 there is nothing to do but to try out the Darwinian factors 

 upon societal phenomena. But upon what shall he try them? 

 Of course, upon the aforesaid cultural adjustments : inven- 

 tions, systems, economies, organizations, and the rest. Are 

 these societal adjustments, like the structural ones of plants 

 and animals, the end-results of variation, selection, and hered- 

 ity, operating in their societal modes and manifestations? 



A great many of the cultural adjustments are, as we see 

 them in institutional form, as in marriage or religion, im- 

 mensely complex. It is expedient to seek them in their simpler 

 phases, just as one would reduce a complex fraction in order to 

 be able to handle it. The simplest form of all societal institu- 

 tions is custom. They all come out of it. Custom is also a 

 conception difficult to handle because it is all-pervasive and 

 eludes the grasp. It required a sort of tour de force to seize, 

 define, and thus reduce to usable form this elusive and floating 

 conception. This was done by my predecessor, Professor 



