ORGANIC EVOLUTION 3^7 



e volution idea is not merely a new light on the special region 

 of biological sciences, zoology and botany, but is of quite 

 general importance. The conception of an evolution of life 

 upon the earth reaches far beyond the bounds of any sin- 

 gle science, and influences our whole realm of thought. It 

 means nothing less than the elimination of the miraculous 

 from our knowledge of nature, and the placing of the phe- 

 nomena of life on the same plane as the other natural proc- 

 esses, that is, as having been brought about by the same 

 forces and being subject to the same laws." 



One feature of the doctrine is very interesting; it has 

 enabled anatomists to predict that traces of certain structures 

 not present in the adult will be found in the embryonic condi- 

 tion of higher animals, and by the verification of these predic- 

 tions, it receives a high degree of plausibility. The presence 

 of an OS centrale in the human wrist was predicted, and after- 

 ward found, as also the presence of a rudimentary thirteenth 

 rib in early stages of the human body. The predictions, of 

 course, are chiefly technical, but they are based on the idea 

 of common descent and adaptation. 



It took a lonsf time even for scientific men to arrive at a 

 belief in the continuity of nature, and having arrived there, 

 it is not easy to surrender it. There is no reason to think 

 that the continuity is broken in the case of man's develop- 

 ment. Naturalists have now come to accept as a mere state- 

 ment of a fact of nature that the vast variety of forms of life 

 upon our globe has been produced by a process of evolution. 

 If this position be admitted, the next question would be, 

 What are the factors which have been operative to loring this 

 about? This brings us naturally to discuss the theories of 

 evolution. 



