290 THE SCHOOL OF REAUMUR 



supposed that the process was started at the Creation, 

 and has been in operation ever since ; there is really no 

 such thing as generation, but only the expansion of 

 germs which are as old as the world. ^ Swammerdam 

 (supra, p. 183) had already published a speculation 

 which has much in common with Bonnet's. 



The formation of hybrid animals and plants, and 

 the resemblance of the child to the father, show that the 

 development of an embryo may be largely affected by 

 events immediately preceding, but awkward facts like ^i 

 these might perhaps be got over by the ingenuity of ™ 

 a Bonnet. The process of embryo-formation is however . 

 absolutely different from that which he pictured to ■! 

 himself. Even in 1759 Wolff saw enough of this process ^ 

 to satisfy himself that the embryo is new-formed in 

 each generation, and his conclusion is now reinforced by 

 the far more complete and rigorous demonstrations 

 of modern embryology. 



The Scale of Creation 



Like other philosophers, Bonnet was prone to affirm 

 things that can never be known. He had picked up 

 from Leibnitz ^ the saying, Natura no7i facit saltum, 

 and not realising the enormous difficulty of proving so 

 comprehensive a negative, he applied instead of scrutin- 

 ising the maxim. Thus he came by his chain of organ- 

 ised beings, a linear series of insensibly graded natural 

 objects, which leads from the four elements to man. 

 Between the different " classes and genera " Bonnet 

 finds connecting links (''points de passage ou de liaison"). 



igee Bonnet's " Accroissement des Germes," CEuvres, Tom. V, pp. 1-11 

 (1781). 



2 '* Rien ne se fait tout d'un coup, et c'est une de mes grandes maximes et des 

 plus verifiees, que la nature ne fait jamais de sauts. J'appelais cela la lot de la 

 continuity, lorsque j'en parlais autrefois dans les Nouvelles de la rdpuhlique 

 des lettres.'' (Leibnitz, preface to Nouveaux Essais.) 



I 



