ANTICIPATION AND INTERPRETATION 29 



A hard preliminary battle had to be fought 

 by the philosophers for natural causation as 

 against supernatural interference in the govern- 

 ing of the living world. Here lies the main debt 

 of natural science to philosophy; and to omit 

 mention of the great names of Descartes, Spi- 

 noza, Leibnitz, and Kant in the seventeenth and 

 eighteenth centuries would leave a serious gap in 

 these outlines. The natural philosophers of this 

 time were actually more scientific than the pro- 

 fessed scientists. They reached below metaphysics 

 into questions which today are left more exclu- 

 sively to science. The order of the universe and 

 the laws of Xature formed a large part of specu- 

 lation from the time of Bacon to that of Schel- 

 ling; in fact, now and again tliis speculation 

 sprang directly from observation of Nature, and 

 it is a most striking fact that every great phi- 

 losopher touched upon the evolution idea. Bruno 

 was a radical evolutionist, although his notions 

 were more Oriental than European. Bacon fore- 

 saw the close bearings of the variation of ani- 

 mals and plants and of experimental Evolu- 

 tion upon species transformation. Descartes cau- 

 tiously advocated the evolution idea and the 

 domain of natural causation. Leibnitz may even 

 be considered the head of a school of evolution- 

 ists. Kant in his earlier writings held advanced 

 views. Thus the early naturalists, whenever they 



