Iiitergejietic Co7icurrence 41 



of the individuals secured for a life in some degree of gre- 

 garious habit, and we then find the great bend in the line. 

 Progress from now on ushers in the dominance of mind in 

 the modes of conscious organization which characterize 

 social life and institutions. 



§ 3. httergenetic Concurrence 



The third question, mentioned above as involved in a 

 full statement of the problem of determination, is that of 

 the relation of the determination of development to that 

 of evolution ; that of the ' intergenetic ' relation of the two 

 lines of progress, growth, and descent. 



We now find that the principles so far explained above, 

 will, if they be true, afford an answer to this ques- 

 tion also. The determination of the direction of evo- 

 lution has been found to follow that of development. 

 There is, therefore, in its great outline the 'concurrence' 

 which the theory of recapitulation supposes, and which 

 it is reasonable to expect if the correlations already ^ men- 

 tioned between the two series are actually realized. The 

 determination of the individual's development is by a 

 process of adjustment to a more or less stable environment. 

 The evolution of the race is throughout, in its great 

 features, a series of adaptations to the same bionomic 

 conditions. Moreover, by the estabHshing of a tradition 

 throughout the life history of the higher forms, there is 

 set up a series of modes of behaviour to which, as we have 

 seen, both development and evolution, by the operation 

 of organic and natural selection, tend ever more approxi- 

 mately to conform. The two movements are, therefore, 

 * concurrent ' in a very well-defined sense. 



1 Cf. Chap. XIII. § 5, below. 



