190 DESCARTES' DISCOURSE ON METHOD iv 



as the grey matter has extension, that which is 

 lodged in it must also have extension. And thus 

 we are led, in another way, to lose spirit in matter. 



In truth, Descartes' physiology, like the modern 

 physiology of which it anticipates the spirit, leads 

 straight to Materialism, so far as that title is 

 rightly applicable to the doctrine that we have no 

 knowledge of any thinking substance, apart from 

 extended substance ; and that thought is as much 

 a function of matter as motion is. Thus wt- ar- 

 rive at the singular result that, of the two paths 

 opened up to us in the " Discourse upon Method," 

 the one leads, by way of Berkeley and Hume, to 

 Kant and Idealism ; while the other leads, by way 

 of De La Mettrie and Priestley, to modern phy- 

 siology and Materialism. 1 Our stem divides into 

 two main branches, which grow in opposite ways, 

 and bear flowers which look as different as they 

 can well be. But each branch is sound and healthy, 

 and has as much life and vigour as the other. 



If a botanist found this state of things in a new 

 plant, I imagine that he might be inclined to 

 think that his tree was monoacious that the 



1 Bouillier, into whose excellent History of the Cn 

 Philosophy I had not looked wlu-n this passage was written, 

 says, very justly, that Descartes " a merite le titre de pere de la 

 physique, aussi bien que cclui do ]>.' -n- d- la met;i]>hysique 

 moderne" (t. i., p. 197). See also Kuno Fischer's (1,-schichtc 

 der neucn Philosophic; Bd. i. ; and the very remarkuMt: work 

 of Lange Geschichtc des Materialismus. A good translation 

 of the latter would be a great service to philosophy in England. 

 [It now exists, 1892.] 



