24 CERTAIN EVIDENCE OF 



ledge of effective causes, and was able to raise 

 itself from the humble rank of a descriptive study 

 of forms to the high position of an analytical science 

 of form. It is true that by the beginning of this 

 century the most comprehensive branch of morphology 

 i.e., comparative anatomy which was founded by 

 Cuvier and splendidly developed by Johannes Miiller, 

 had laid the foundations on which to build a truly 

 philosophical science of form. The enormous mass of 

 various empirical material, which had been accumulated 

 by descriptive systematists and by the dissections of 

 zootomists since the time of Linnaeus and Pallas, had 

 already been abundantly matured and utilised in many 

 ways for philosophic purposes by the synthetic prin- 

 ciples of comparative anatomy. But even the most 

 important universal laws of organisation of which 

 the old system of comparative anatomy was one had 

 to take refuge in mystical ideas of a plan of structure 

 and of creative final causes (causes finales) ; they were 

 incapable of arriving at a true and clear perception of 

 effective mechanical causes (causoe efficientes). This 

 last, most difficult, and grandest problem, Charles 

 Darwin was the first to solve in 1859, by setting 

 Lamarck's theory of descent, which was already fifty 

 years old, on a firm footing by his own theory of 

 selection. By this hypothesis it was first made 

 possible to fit together the rich materials which had 



