CHAPTER II 



THEORIES OF EVOLUTION 



The Bathmic Theory The Lamarckian Theory The Nee-Darwinian 

 Theory The alleged inheritance of acquired characters Mutila- 

 tions Maternal impressions Diseases. 



22. WE need not devote much space to the Bathmic theory 

 of evolution. It has now very few followers. It supposes 

 that evolution has occurred in obedience to, and under the 

 immediate direction of, a Deity who has rejected both 

 Natural Selection and the transmission of acquirements as 

 means to His ends. It is, in effect, a theory of evolution by 

 ever-recurring miracles. Even if we postulate a Deity as the 

 Originator of all things, yet the whole history of science, 

 which is that of civilization, proves that it is more profitable 

 to seek the explanation of natural phenomena in natural laws 

 (His laws) than in infractions of them in miracles. Only 

 when a natural explanation has been proved to be impossible 

 have we an excuse for a direct appeal to the supernatural. 

 As scientific men we may have faith in a Deity ; we may 

 suppose that the universe is one great miracle ; but, except 

 on entirely authentic and decisive evidence of a kind as yet 

 unobtainable, we must not suppose that it is governed by 

 discontinuous miracle. 



23. Of course the theory of Bathmic evolution may be 

 enunciated in vague terms. God and miracle need not be 

 mentioned. We may be told that species undergo evolution, 

 and so adapt themselves to the changing conditions of 

 existence, not by the action of Natural Selection nor by the 

 transmission of acquirements, but simply through the opera- 

 tion of an inherent adaptive " growth-force." Nevertheless 

 the appeal to miracle is still necessary. No doubt the 

 universal existence of variations demonstrates the existence 

 of a growth, or rather change-force. But the difficulty which 

 has to be surmounted by the Bathmic evolutionist arises, not 



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