60 GERMINAL SELECTION. 



the guidance of variation by utility, which we have 

 considered to-day. For without primary constituents 

 of the germ, whether they are called as I call them, 

 determinants, or something else, germinal selection, 

 or guidance of variation by personal selection, is im- 

 possible; for where all units are alike there can be 

 no struggle, no preference of the best. And yet such 

 a guidance of variation exists and demands its ex- 

 planation, and the early assumptions of a "definitely 

 directed variation" such as Nageli and Askenasy made 

 are insufficient, for the reason that they posit only 

 internal forces as the foundations thereof, and be- 

 cause, as I have attempted to show, the harmony of the 

 direction of variation with the requirements of the 

 conditions of life subsists and represents the riddle 

 to be solved. The degree of adaptiveness which a 

 part possesses itself evokes the direction of variation 

 of that part. 



This proposition seems to me to round off the whole 

 theory of selection and to give to it that degree of in- 

 ner perfection and completeness which is necessary to 

 protect it against the many doubts which have gath- 

 ered around it on all sides like so many lowering 

 thunder-clouds. The moment variation is determined 

 substantially though not exclusively by the adaptive- 

 ness itself, all these doubts fall to the ground, with 

 one exception, that of the utility of the initial steps. 

 But just this objection is the least weighty. Without 

 doubt the theory requires that the initial steps of a 

 variation should also have selective value ; otherwise 

 personal selection and hence germinal selection could 

 not set in. Since, however, as I have before pointed 

 out, in no case can we pretend to a judgment regard- 

 ing the selective value of a modification, or have any 



