196 ORGANIC EVOLUTION — MENTAL 



acquired characters, are no criteria whereby to decide 

 whether this or that additional variation is an acquired 

 variation or not. If we bear these three cardinal truths 

 well in mind during the ensuing discussion we shall 

 find that while they supply means of solving many 

 problems of the highest importance, and explaining 

 many mysteries hitherto held to be inscrutable, they 

 are themselves amply and often beautifully confirmed 

 by the study in its deeper aspects of the Natural 

 History of Man. 



