ARE ANIMALS AUTOMATONS? 725 



circulation of the blood, and by that remarkable discovery of his he 

 laid the foundation of a scientific theory of the larger part of the pro- 

 cesses of living beings — ^those processes, in fact, which we now call 

 processes of sustentation — and by his studies of development he first 

 laid the foundation of a scientific knowledge of reproduction. But, 

 besides these great powers of living beings, there remains another 

 class of functions — those of the nervous system — with which Harvey 

 did not grapple. It was, indeed, left for a contemporary of his, Rene 

 Descartes, to play a part in relation to the phenomena of the nervous 

 system which is precisely equal in value to that Harvey played in re- 

 gard to the circulation. You must recollect that this man Descartes 

 was not merely, as some had been, a happy speculator. He was a 

 working anatomist and physiologist, conversant with all the anatomi- 

 cal and physiological law of his time. A most characteristic anecdote 

 of him, and one which should ever put to silence those shallow talkers 

 who speak of Descartes as an hypothetical and speculative philosopher, 

 is, that a friend once calling upon him in Holland begged to be shown 

 his library. Descartes led him into a sort of shed, and, drawing aside 

 a curtain, displayed a dissecting-room full of the bodies of animals in 

 course of dissection, and said, " There is my library." 



The matters of which we shall treat are such as to require no ex- 

 tensive knowledge of anatomy. I need only premise that what we 

 call the nervous system in one of the higher animals consists of a cen- 

 tral apparatus, composed of the brain, which is lodged in the skull, 

 and of a cord proceeding from it, which is termed the spinal marrow, 

 and which is lodged in the vertebral column or spine, and that then 

 from these soft white masses — for such they are — there proceed cords 

 which are termed nerves, some of which nerves end in the muscle, 

 while others end in the organs of sensation. The first proposition 

 that you find definitely and clearly stated by Descartes is the view 

 that the brain is the organ of sensation, of thought, and of emotion — 

 using the word " organ " in this sense, that certain changes which 

 take place in the matter of the brain are the essential antecedents of 

 those states of consciousness which we term sensation, thought, and 

 emotion. If your friend disagrees with your opinion, runs amuck 

 against any of your pet prejudices, you say, " Ah ! poor fellow, he is 

 a little touched here," by which you mean that his brain is not doing 

 its business properly — that he is not thinking properly — thereby im- 

 plying that his brain is some way affected. It remained down to 

 the time of Bichat a question whether the passions were or were not 

 located in the abdominal viscera. In the second place, Descartes lays 

 down the proposition that all the movements of the animal bodies are 

 effected by the change of form of a certain part of the matter of their 

 bodies, to which he applies the general term of muscle. That is a 

 proposition which is now placed beyond all doubt whatever. If I 

 move my arm, that movement is due to the change of this mass in 



