SPENCER'S CONTRIBUTIONS 



our intelligence, while that which is manifested lies 

 beyond it." Subsequent study affords no indica- 

 tion that the mystery will ever be solved. The 

 production of life in the laboratory, which is yet a 

 very long way off, would not in the smallest degree 

 serve to reveal to us the essential nature of life, 

 whose "phenomena are accessible to thought, but 

 the implied noumenon is inaccessible." 1 Neverthe- 

 less, for the fullest philosophic consideration of the 

 problem of life, philosophic in the sense of being 

 broad, not of being verbal and in the last resort 

 no more, the student must consult these pages. 



Let us next note another little-known but im- 

 portant contribution to general evolutionary theory 

 which we owe to Spencer the biologist. Every 

 living organism begins as a single cell; but there 

 invariably comes a time when, if the cell reaches 

 a certain size, it begins to divide. It is this divi- 

 sion that conditions the development of the hetero- 

 geneous multicellular individual from the homo- 

 geneous unicellular creature which, whatever the 

 size to which it grew, could never be other than a 

 lowly and primitive object. Now, Spencer's law 

 of limit of growth teaches that, as a cell enlarges, 

 its volume increases at a greater rate than its sur- 

 face, as is evident. Now it is by its surface that 

 the cell maintains its relations with its environ- 

 ment and absorbs nutriment. The limit of cell- 

 size is therefore a mechanical problem. When the 



1 Latest edition of^he Biology, I., 120. 

 157 



