Exfoliation 



that it was some nobler power that worked trans- 

 forming some dim desire and prevision of a 

 more perfect form, the desire itself being the 

 first consciousness of the urge of growth in that 

 direction that prompted him to push in the one 

 direction rather than the other when he had to 

 hold his own against the tigers ? In fact is it not 

 thus to-day, when a man has to meet danger, that 

 the ideal which he has within him determines 

 how he shall meet that danger, and others like it, 

 and so ultimately determines the whole attitude 

 and carriage of his body ? 



On the whole then, judging from man himself 

 (and it seems most cautious and scientific to derive 

 our main evidence from the being that we are 

 best acquainted with), it certainly seems to me 

 that, though the external conditions are a very im- 

 portant factor in Variation, the central explana- 

 tion of this phenomenon should be sought in an 

 inner law of Growth a law of expansion more or 

 less common to all animate nature. Partly because, 

 as said before, the unfolding of the creature from 

 its own needs and inward nature is an organic 

 process, and likely to be persistent, while its 

 modification by external causes must be more 

 or less fortuitous and accidental and sometimes 

 in one direction and sometimes in another ; partly 

 also because the movement from within outwards 

 seems to be most like the law of creation in general. 

 Under this view the external conditions would 

 be considered a secondary though important 

 cause of modification ; and regarded rather as 



191 



