2 PROBLEMS OF FERTILIZATION 



From the time of the Greeks to that of Harvey 

 (165 1) there was but little progress in the knowledge of 

 reproduction and none in the theory, as will appear 

 from the views of Aristotle, the current views of medical 

 men of Harvey's time, and of Harvey himself. Aristotle 

 says : 



The male is the efficient agent, and by the motion of his genera- 

 tive virtue (genitura), creates what is intended from the matter 

 contained in the female; for the female always supplies the matter, 

 the male the power of creation, and this it is which constitutes 

 one male, another female. The body and the bulk, therefore, 

 are necessarily supplied by the female; nothing of the kind is re- 

 quired from the male; for it is not even requisite that the instru- 

 ment, nor the efficient agent itself, be present in the thing that is 

 produced. The body then proceeds from the female, the vital 

 principle (anima) from the male; for the essence of every body is 

 its vital principle (anima). ^ 



With more common sense, if with less metaphysical 

 subtlety, the physicians of the Middle Ages held, accord- 

 ing to Harvey, that conception is due to a mingling of 

 male and female seminal fluids, ''the mixture having 

 from both equally the faculty of action and the force of 

 matter; and according to the predominance of this or 

 that geniture does the progeny turn out male or female" 

 (quoted from Harvey, Ex. 32). 



Harvey's observations contained much that was new 

 and significant, and the facts that he discovered were 

 inconsistent both with Aristotle's ideas and with those 

 of the physicians. They were, however, inadequate for 

 sound generalization. 



Wandering between two worlds, one dead 

 The other powerless to be born, 



^ De Gen. Anim. ii. 4, quoted from Harvey, "On the Generation of 

 Animals," Ex. 29. 



