EXCURSIONS OF AN EVOLUTIONIST 



will leave the next generation somewhat better 

 equipped than their parents for meeting these 

 exigencies. Those men whom we regard as con- 

 spicuously successful in life using the term 

 " successful " in no narrow and mercantile, but 

 in the broadest possible sense are the men, 

 more or less numerous, whose mental capacity 

 rises somewhat above this average standard. A 

 like number of men, through various kinds and 

 degrees of ill success, reveal a mental capacity 

 that is more or less below the average. And 

 along with these numerous moderate variations 

 from the common level we meet in every age 

 with a few extreme variations, men of giant 

 intelligence, such as Darwin or Helmholtz, who 

 rise as far above the average of the race as idiots 

 and cretins sink below it. 



Now the moth with his proboscis twice as 

 long as the average, or the man eight feet in 

 height, is what we call a spontaneous variation, 

 and the Darwin or the Helmholtz is what we 

 call a " genius ; " and the analogy between the 

 two kinds of deviation is obvious enough. But 

 obviously, too, the individual which we single 

 out as a spontaneous variation is in no wise es- 

 sentially different from his fellow-individuals. 

 If five feet and eight inches be the normal height 

 of a race of men, the man who measures six 

 feet is a variation as much as he who measures 

 eight, only the one instance does not attract 

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