Harvey's merits are undoubtedly overstated by his British 

 compatriot J(oseph) Needham, who dedicated several enthusi- 

 astic pages to him. .Needham was obliged to admit that Harvey 

 "did not break with Aristotelianism, . . . but on the contrary 

 lent his authority to a moribund outlook . . . ." 



Harvey's opinions were much more objectively evaluated 

 by an early historian of biology, J. Beseke, in his book 

 published in Russia at the end of the eighteenth century. ^ 

 Beseke noted that "the plastic power" by which Harvey tried 

 to explain Aristotelian epigenesis, in fact did not explain 

 anything, and that Harvey, with his presentation about the 

 three ways of generation, was in fact far from his own 

 principle that "An egg is the common origin of all animals." 

 Proof of this latter general conclusion does not belong to 

 Harvey but to (Francesco) Redi, who proved experimentally 

 that the larvae of meat flies develop not from rotten meat, 

 but from eggs laid by the flies. 



In the middle of the seventeenth century the defense 

 of epigenetic opinions, as J. Needham correctly noted, was 

 a step backwards towards Aristotle. It did not require the 

 courage and independence of ideas which proved necessary at 

 the middle of the eighteenth century, when the ideas of 

 preformation became predominant . The emergence of these 

 preformationist ideas began in the second half of the 

 seventeenth century, connected with the oblivion of Descartes' 

 philosophical opinions and Harvey's theoretical propositions. 

 Descartes' biological opinions, mechanical and epigenetic 

 in character, had an acknowledged influence on the development 

 of embryology. His presentations about the embryonic develop- 

 ment of animals are stated in the treatise, "Treatise on the 

 Human Body." (9) 



2. JCoseph) Needham, A HISTORY OF EMBRYOLOGY, 



pp. 166 - 167. [Ed.: References are to the German edition, 

 p. 149 of 2nd ed., New York: Abelard-Schuman, 1959.) 



3. Jtohann] M(elchior) G(ottlieb) Beseke, VERSUCH EINER 

 GESCHICHTE DER HYPOTHESEN OBER DIE ERZEUGUNG 

 DER THIERE, WIE AUCH EINER GESCHICHTE DES 

 URSPRUNGS DER EINTEILUNG DER NATURKORPER IN DREY 

 RE I CHE. Mitau, Steffenhagen, 1797 (12 unnumbered + 



130 pp.) . 



36 



