38 The Direction of Evolution 



forms can live in which congenital variation is in some 

 way either * coincident ' with^ or correlated with ^ the indi- 

 vidual accommodations which serve to bri?ig the creatures to 

 maturity. Variations which aid the creatures in their 

 struggle for existence will, where definite congenital en- 

 dowment is of utility, be taken up by the accommoda- 

 tion processes, and thus accumulated to the perfection 

 of certain characters and functions. The evolution of 

 plasticity, on the other hand, could only itself have taken 

 place by the cooperation of accommodation using the 

 variations toward plasticity already present at each stage, 

 and thus saving and developing such variations. This gave 

 an ever higher platform of variation from which steady 

 refinement of plasticity and its accompanying intelligence 

 was all along possible. Organic selection becomes, accord- 

 i?tgly, a tcniversal principle, provided, and ifi so far as, 

 accommodation is universal. 



Accommodation, therefore, when all is said, is a posi- 

 tive thing, a vital and mental functional process supple- 

 mentary to the hereditary impulse. It must be considered 

 a positive factor in evolution, a real force emphasizing 

 that which renders an organism fit ; whereas natural selec- 

 tion, while a necessary condition, is yet a negative factor, 

 a statement that the most fit are those which survive. If 

 it be true that those variations which can accommodate, 

 either very much or very little, to critical conditions of 

 life are the ones to survive, and that such variations will 

 be accumulated and will in turn progressively support 



1 See below, Chap. XIV., for treatment of the distinction indicated by 

 these phrases. ' Coincident variation ' was suggested by Professor Lloyd Mor- 

 gan : cf. below, Chap. XL § i, and Lloyd Morgan's Animal Behaviour, 

 P-37- 



