ANTICIPATION AND INTERPRETATION 17 



sprung up and succeeded in firmly entrenching 

 itself, so that Darwin and Wallace began the 

 final era with some abruptness. 



Evolution as a Law of Nature 



In the twenty-four centuries between Thales 

 and Darwin, as we have seen in this resume, the 

 idea had a long struggle for growth and exist- 

 ence, yet it never wholly suspended animation. 

 I may emphasize again the standpoint of these 

 chapters, that the final conception of Evolution 

 is to be regarded as a cluster of many subsidiary 

 ideas, which slowly evolved in the environment 

 of advancing human knowledge. Like an animal 

 or plant made up of many different parts which 

 have been added one by one along the ages, we 

 can take up this history as we should a bit of 

 biological research; consider the idea as living 

 and still growing, and seek the first stages of 

 each of its parts. These we wall find in the earliest 

 guesses as to the origin of life from lifeless mat- 

 ter; in conjectures about embryonic development 

 and reproduction; in early observed evidences of 

 heredity, degeneration, variation, and of the affil- 

 iation between organisms; in the first apprecia- 

 tion of environment and its influences in modi- 

 fying animal and plant form and function, of 

 internal changes in the body and their influences, 

 of the principle of adaptation or fitness of the 



