THE LIFE VARIES AS THE CORRESPONDENCE. 87 



of each species of organism it might finally be shown that 

 the same general truth is displayed in the history of mankind : 

 whose advance in civilization has been simultaneous with 

 their advance from the less varied requirements of the torrid 

 zone to the more varied requirements of the temperate zone; 

 whose chief steps have been made in regions presenting a 

 complicated physical geography ; and who, in the course of 

 their progress, have been adding to their physical environ 

 ment a social environment that has been growing even more 

 involved. Thus, speaking generally, it is clear that those re 

 lations in the environment to which relations in the organism 

 must correspond, themselves increase in number and intricacy 

 as the life assumes a higher form. 



34. To make yet more manifest the fact, that the degree 

 of life varies as the degree of correspondence, I may here 

 point out, that those other distinctions successively noted 

 when contrasting vital changes with non-vital changes, are 

 all implied in this last distinction their correspondence 

 with external co-existences and sequences. And to this may 

 be added the supplementary fact, that the increasing fulfil 

 ment of those other distinctions which we found to accompany 

 increasing life, is involved in the increasing fulfilment of this 

 last distinction. To descend to particulars : We saw that 

 living organisms are characterized by successive changes ; 

 and that as the life becomes higher, the successive changes 

 become more numerous. Well, the environment is full of 

 successive changes, both positive and relative ; and the 

 greater the correspondence, the greater the number of suc 

 cessive changes an organism must display. We saw that life 

 presents simultaneous changes ; and that the more elevated 

 it is, the more marked the multiplicity of them. Well, 

 besides countless phenomena of coexistence in the environ 

 ment, there are often many changes occurring in it at the 

 same moment ; and hence increased correspondence with it, 

 supposes an increased display of simultaneous changes in the 



