INTR OD UCTION, 



Outlines of the Whole Development. 



The history, as a whole, before Darwin, at first 

 sight appears to have been mainly the anticipation y^ 

 of Nature; but closer examination reveals much 

 genuine Interpretation of Nature. Before the mid- 

 dle of this century, In fact, natural science was not 

 ready for Evolution on the Inductive line. The 

 way had to be paved for it; one proof of this is 

 found in the failure of the strong Evolution move- 

 ment in France during the latter part of the last, 

 and beginning of this century. In the middle of 

 this century came the time and the man who ranks 

 as the great central thinker. Under the Impetus of 

 Darwin, the first steps were to establish, as a natural 

 law, what had ranked as an hypothesis or theory, 

 and this has been most thoroughly done In the last 

 thirty-five years. We are now taking our uncertain 

 steps in search of the separate factors of this law, 

 and cannot foresee when these will be completed. 

 ' Before and after Darwin ' will always be the ante 

 et post urbem conditam of biological history. Before. 

 _DarwIn, the theory; after Darwin, the factors. 



We remember that there are usually three stages 

 In connection with the discovery of a law of Nature ; 

 first, that of dim suggestion in pure speculation, 

 with eyes closed to facts; second, that of clear 

 statement as a tentative or working hypothesis in 

 an explanation of certain facts; and finally, the 



