THE WONDERS OF LIFE 



greatest achievement — the establishment of the science 

 of evolution by Darwin. To this we must add the 

 psychological metamorphosis (similar to that of Wundt, 

 Baer, Dubois-Reymond, and others), of which I have 

 spoken in the sixth chapter of the Riddle. The extraor- 

 dinary authority of Virchow, and the indefatigable zeal 

 with which he struggled every year until his death 

 (1903) against the descent of man from other verte- 

 brates, caused a wide-spread opposition to the doctrine 

 of evolution. This was supported especially by Johan- 

 nes Ranke, of Munich, the secretary of the Anthro- 

 pological Society. Happily, a change has recently set 

 in. However, my Antkropogeny has remained for thirty 

 years the only work of its kind — namely, a comprehen- 

 sive treatment of man's ancestral history, especially in 

 the light of embryology. 



As I pointed out in the eighth and ninth chapters of 

 the Riddle, the most solid foundation of our monistic 

 psychology is the fact that the human mind grows. 

 Like every other function of our organism, our mental 

 activity exhibits the phenomenon of development in 

 two directions, individually in each human being and 

 phyletically in the whole race. The ontogeny of the 

 mind — or the embryology of the human soul — brings 

 before us in direct observation the various stages of 

 development through which the mind of every man 

 passes from the beginning to the close of life. The 

 phylogeny of the mind — or the ancestral history of the 

 human soul — does not afford us this direct observation ; 

 it can only be deduced by a comparison and synthesis of 

 the historical indications which are supplied by history 

 and prehistoric research on the one hand, and the 

 critical study of the various stages of mental life in 

 savages and the higher vertebrates on the other. In 

 this the biogenetic law is used with great success (chapter 

 xvi.). 



322 



