VI EVOLUTION IN BIOLOGY 207 



generalcment la nature de toutes les choscs qui sont au monde si 

 nous pouvons imaginer quelques principes qui soient fort intelli- 

 gibles et fort simples, desquels nous puissionsvoirclairement que 

 les astres et la terre et enfin tout ce monde visible auroit pu etre 

 produit ainsi que de quelques semences (bien que nous sachions 

 qu il n a pas etc produit en cette fa9on) que si nous la decrivions 

 seulement comme il est, ou bicu comme nous croyons qu il a ete 

 cree. Et parceque je pense avoir trouve des principes qui sont 

 tels, je tacherai ici de les expliquer.&quot; l 



If we read between the lines of this singular 

 exhibition of force of one kind and weakness of 

 another, it is clear that Descartes believed that he 

 had divined the mode in which the physical uni 

 verse had been evolved ; and the &quot; Traite de 

 I Homme,&quot; and the essay &quot; Sur les Passions &quot; afford 

 abundant additional evidence that he sought for, 

 and thought he had found, an explanation of the 

 phenomena of physical life by deduction from 

 purely physical laws. 



Spinoza abounds in the same sense, and is as 

 usual perfectly candid 



&quot;Natune leges et regul, secundum quas omnia fiunt ct ex 

 unis formis in alias mutautur, sunt ubique et semper eadem.&quot; 2 



Leibnitz s doctrine of continuity necessarily led 

 him in the same direction ; and, of the infinite 

 multitude of monads with which he peopled the 

 world, each is supposed to be the focus of an end 

 less process of evolution and involution. In the 



1 Principes de la Philosophic, Troisieme partie, 45. 

 3 Ethices, Pars tertia, Prafatio. 



