CHAPTER XXIX 



ON EVIL IN SMALL DOSES 



In all our theories of evolution there is a gap, and one 

 that is fatal, for no argument can be considered complete, 

 rounded off, and quite satisfactory until it is adequately 

 filled in. 



This weak point is the origin of variations. We have 

 seen that climate-changes produce, in all vegetable cells, 

 modifications which are of the nature of fitting responses 

 to a new crisis. But how and why are those modifica- 

 tions, those fitting responses always or at any rate so 

 frequently ready to deal with the new emergency ? 



It is no answer to refer with Weissmann to the germ 

 cells, which are, according to him, immortal, irrespon- 

 sible, and entirely uninfluenced by the experiences of the 

 individual. 



The mutant of De Vries is again not an explanation, 

 but a new name for a change of type. 



Many attempts have been made to trace the number 

 and character of variations by direct observation and 

 measurement. 



Some of these researches involved an enormous 

 amount of arithmetical calculation and of mathematical 

 ingenuity which unfortunately makes it impossible for 

 any one save mathematicians to appreciate them as they 

 deserve.^ 



But on the whole these biometrical researches dis- 

 tinctly show that in any one generation, and if a single 

 measurable character is taken, the majority of individuals 

 are found to have the average character, and that those 



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