pearl: biology and war 345 



conduct of business may be tolerated, and a thousand other of 

 the complex and manifold relations between human beings. 



True evolutionary change in a strict philosophical sense means 

 a definite and permanent alteration in a group of organisms, both 

 in the group as a whole and in the individuals composing it, as 

 individuals. When one uses the term "permanent" in this con- 

 nection it should, of course, be understood always to carry the 

 qualification, permanent until the conditions which produced 

 the initial evolutionary change themselves become altered. Now 

 human social evolutionary change rests upon two broad general 

 bases instead of the one upon which the organic evolution of lower 

 forms of life depends. Lack of recognition of this fact has been a 

 fruitful source of failure to arrive at philosophically sound con- 

 clusions in many discussions of the social evolution of man, under- 

 taken from the biological point of view. 



The basic element and limiting factor in organic evolution is 

 the germ plasm. It is at once the race stabilizer and the race 

 initiator. The germ plasm is the physical basis of inheritance in 

 general. Borne in the reproductive cells of the organism it is 

 the one thing which preserves physical continuity between suc- 

 cessive generations of organisms. If successive generations are to 

 differ from one another biologically there must be concomitant 

 and equivalent changes in the germ plasm. Genetic and eugenic 

 research has abundantly proven that the germ plasm plays the 

 same role in human inheritance and human evolutionary changes 

 that it does in lower organisms. Here one needs only to mention 

 the studies of Galton, Pearson, and Davenport by way of illus- 

 tration. Many others might be added to the list. 



Besides this strictly biological base of the germ plasm there is 

 also another underlying factor in human social evolution which 

 is nearly, if not quite, of as great significance. I refer to that com- 

 plex of ideas and actions which has been rather badly called 

 "social inheritance." This factor operates in somewhat the 

 following manner. Starting from a germ-plasmic base the indi- 

 viduals composing any social group are biologically differentiated 

 from those forming other social groups. On this account they 

 develop social relations and social institutions of a sort in some 



