HEREDITY 



tion has been undoubtedly the efficient cause o 

 change in both cases, but how and why applie< 

 and to what sort of material is as uncertaii 

 in one case as in the other. The few grea 

 men who have succeeded in producing by thei 

 individual efforts a new and more useful typ 

 of animal or plant have worked largely b; 

 empirical methods. They have produced ; 

 desired result but by methods which neithe 

 they nor any one else fully understood o 

 could adequately explain. So there exists a 

 yet no true science of breeding but only ; 

 highly developed art which was practiced a 

 successfully by the ancient Egyptians, th 

 Saracens, and the Eomans as by us. Th 

 present, however, is an age of science; w 

 are not satisfied with rule-of-thumb methods 

 we want to know the why as well as the hoi 

 of our practical operations. Only such knowl 

 edge of the reasons for methods empirically 

 successful can enable us to drop out of ou 

 practice all superfluous steps and roundabou 

 methods and to proceed straight to the marl 

 in the most direct way. The industrial his 

 tory of the last century is full of instances ii 



4 



