74 CREATIVE EVOLUTION [chap. 



of the "kaleidoscopic" character of the variation, 1 or 

 when he says that the variation of organized matter works 

 in a definite way, just as inorganic matter crystallizes in 

 definite directions. 2 And it may be granted, perhaps, 

 that the process is a merely physical and chemical one in 

 the case of the color-changes of the skin. But if this sort 

 of explanation is extended to the case of the gradual forma- 

 tion of the eye of the vertebrate, for instance, it must be 

 supposed that the physico-chemistry of living bodies is 

 such that the influence of light has caused the organism 

 to construct a progressive series of visual apparatus, all 

 extremely complex, yet all capable of seeing, and of seeing 

 better and better. 3 What more could the most confirmed 

 finalist say, in order to mark out so exceptional a physico- 

 chemistry? And will not the position of a mechanistic 

 philosophy become still more difficult, when it is pointed 

 out to it that the egg of a mollusc cannot have the same 

 chemical composition as that of a vertebrate, that the 

 organic substance which evolved toward the first of these 

 two forms could not have been chemically identical with 

 that of the substance which went in the other direction, 

 and that, nevertheless, under the influence of light, the 

 same organ has been constructed in the one case as in 

 the other? 



The more we reflect upon it, the more we shall see that 

 this production of the same effect by two different ac- 

 cumulations of an enormous number of small causes is 

 contrary to the principles of mechanistic philosophy. 

 We have concentrated the full force of our discussion upon 

 an example drawn from phylogenesis. But ontogenesis 

 would have furnished us with facts no less cogent. Every 



1 Eimer, Orthogenesis der Schmetterlinge, Leipzig, 1897, p. 24. Cf. 

 Die Entstehung der Arten, p. 53. 



* Eimer, Die Entstehung der Arten, Jena, 1888, p. 25. 



• Ibid. pp. 165 ff. 



