264 THE RIDDLE OF THE UNIVERSE. 



physiological theory of descent (1884), and has 

 represented it to be an indispensable thesis in any 

 natural theory of evolution. I entirely agree with 

 his assertion that " to reject abiogenesis is to admit 

 a miracle." 



The hypothesis of spontaneous generation and the 

 allied carbon- theory are of great importance in 

 deciding the long-standing conflict between the teleo- 

 logical (dualistic) and the mechanical (monistic) inter- 

 pretation of phenomena. Since Darwin gave us the 

 key to the monistic explanation of organisation in his 

 theory of selection forty years ago, it has become 

 possible for us to trace the splendid variety of orderly 

 tendencies of the organic world to mechanical, natural 

 causes, just as we could formerly in the inorganic 

 world alone. Hence the supernatural and telic forces, 

 to which the scientist had had recourse, have been 

 rendered superfluous. Modern metaphysics, however, 

 continues to regard the latter as indispensable and the 

 former as inadequate. 



No philosopher has done more than Immanuel Kant 

 in denning the profound distinction between efficient 

 and final causes, with relation to the interpretation of 

 the whole cosmos. In his well-known earlier work 

 on The General Natural History and Theory of the 

 Heavens he made a bold attempt "to treat the con- 

 stitution and the mechanical origin of the entire fabric 

 of the universe according to Newtonian laws." This 

 " cosmological nebular theory " was based entirely on 

 the mechanical phenomena of gravitation. It was 

 expanded and mathematically established later on by 

 Laplace. When the famous French astronomer was 

 asked by Napoleon I. where God, the creator and 

 sustainer of all things, came in in his system, he 



