V ANIMAL AUTOMATISM 203 



think of him, either as a person who had some 

 preposterous notions about vortices and was 

 deservedly annihilated by the great Sir Isaac 

 Newton ; or as the apostle of an essentially vicious 

 method of deductive speculation ; and that, never- 

 theless, neither the chatter of shifting opinion, 

 nor the silence of personal oblivion, has in the 

 slightest degree affected the growth of the great 

 ideas of which he was the instrument and the 

 mouthpiece. 



It is a matter of fact that the greatest physiolo- 

 gist of the eighteenth century, Haller, in treating 

 of the functions of nerve, does little more than 

 reproduce and enlarge upon the ideas of Descartes. 

 It is a matter of fact that David Hartley, in his 

 remarkable work the " Essay on Man," expressly, 

 though still insufficiently, acknowledges the re- 

 semblance of his fundamental conceptions to those 

 of Descartes ; and I shall now endeavour to show 

 that a series of propositions, which constitute the 

 foundation and essence of the modern physiology 

 of the nervous system, are fully expressed and 

 illustrated in the works of Descartes. 



I. The Irain is the organ of sensation, thought, 

 and emotion; that is to say, some change in 

 the condition of the matter of this organ is 

 the invariable antecedent of the state of 

 consciousness to which each of these terms 

 is applied. 



