216 The Science of Life. 



which mediae valism had amused itself. Men passed 

 surely, though slowly and imperfectly, from hearsay and 

 tradition to observation and experiment, from imagining 

 to induction. During the earlier period of this renais- 

 sance, inquiry was so thoroughly pre-occupied with the 

 observed facts of nature that little attention was paid 

 to the problem of evolution ; thus, before we reach any 

 great evolutionist who was at the same time a concrete 

 naturalist we find (a) a school of philosophic evolution, 

 (b) an abundance of somewhat rank and random specu- 

 lation, and (c) a number of fruitful concrete suggestions 

 in anatomy, physiology, and embryology, which were 

 not connected into a system. 



Prof. Osborn notes the striking fact "that the basis 

 of our modern methods of studying the evolution prob- 

 Phiiosophjc lem was established not by the early natu- 

 Evoiutionists. ra ii s t s , nor by the speculative writers, but by 

 the philosophers. They alone were upon the main track 

 of modern thought." It must be remembered in this 

 connection that many of these philosophers reaped the 

 reward which never fails those who turn with inde- 

 pendent minds to Aristotle and Plato, and that many 

 of them were expert students in some department of 

 natural science. 



Francis Bacon (1561-1626), for ever famous for his 

 insistence on the true method of scientific inquiry by 

 observation, experiment, and induction may be noted 

 here as one of the first to apprehend the possibility of 

 the transmutation of species by accumulated variations, 

 and to propose, what is not even yet realized, an Insti- 

 tute of Experimental Evolution. Ren Descartes (1596- 

 1650) was the Bacon of France, noteworthy for his 

 appreciation of the idea of gradual development and for 

 his daring attempt to explain the universe on physical 

 principles. In regard to both, however, he was fatally 

 inhibited by the orthodox dogma of special creation. 

 Gottfried Wilhelm Leibnitz (1646-1716) is memorable 

 for his doctrine of continuity that all natural orders of 

 beings present but a single chain, along which advance 

 is made by degrees and never by leaps, as the existence 

 of intermediate species clearly shows. The idea of evolu- 



