SECT. 3] AND EIGHTEENTH CENTURIES 147 



Harvey not only follows Aristotle in his good discoveries and true 

 statements about the egg, but also, unfortunately, in his less useful 

 parts, as, for example, when he devotes several pages to the dis- 

 cussion of how far the egg itself is alive, and whether there is any soul 

 in subventaneous or unfruitful eggs. He decides that there is only 

 a vegetative soul. On the other hand, he admirably refutes the 

 opinion of those physicians — who were not few in number — who 

 declared that the foetal organs were all functionless during foetal life. 

 "But while they contende", he says, "that the mother's Blood is 

 the nutriment of the foetus in the womb, especially of the Partes 

 Sanguineae, the bloody parts (as they call them) and that the Foetus 

 is at first, as if it were a part of the mother, sustained by her blood 

 and quickened by her spirits, in so much that the heart beats not 

 and the liver sanguifies not, nor any part of the Foetus doth execute 

 any publick function, but all of them make Holy-Day and lie idle; 

 in this Experience itself confutes them. For the chicken in the egge 

 enjoyes his own Blood, which is bred of the liquors contained within 

 the egge, and his Heart hath its motion from the very beginning, 

 and he borroweth nothing, either blood or spirits, from the Hen, 

 towards the constitution either of the sanguineous parts or plumes, 

 as those that strictly observe it may plainly perceive." We have already 

 seen how the Stoics in antiquity believed that the embryo was a part 

 of the mother until it was born ; from this idea the transition would 

 be easy to the belief that all the organs in the embryo were functionless 

 and dependent on the activity of the corresponding ones in the 

 maternal organism. 



One of Harvey's most important services to thought lay in his 

 abolishing for good the controversy which had gone on ever since 

 the sixth century B.C. about which part of the egg was for nutrition 

 and which for formation. He had the sense to see that the distinction 

 was a useless and baseless one — "There is no distinct part (as we 

 have often said) or disposed matter out of which the Foetus may be 

 formed and fashioned. . . . An egge is that thing, whose liquors do 

 serve both for the Matter and the Nourishment of the foetus.. . .Both 

 liquors are the nourishment of the foetus." 



As regards spontaneous generation, Harvey considered that even 

 the most imperfect and lowest animals came out of eggs. "We shall 

 show", he writes, "that many Animals themselves, especially insects 

 do germinate and spring from seeds and principles not to be discerned 



