x] of the Nervous System. 259 



philosophers, namely that a front ventricle is the receptacle 

 of sensations which, passed on to a second ventricle in the 

 middle of the head, are there used for imagination, reasoning 

 and thought, and that a third ventricle near the back of the 

 head is devoted to memory. " Of such a kind are the figments 

 " of men who have never studied the handiwork of God the 

 " maker of all things as seen in the structure of bodies, but 

 " who take to themselves reckless opinions gathered from all 

 "manner of sources, figments imagined surely not without 

 "grave impiety. How wrong these are in their description 

 "of the structure of the brain the following discourse will 

 " shew." 



It is obvious that Vesalius took a distinctly physiological 

 view of the origin of the chief soul. The chief soul is to him 

 the totality of the animal spirits just as the vital soul is the 

 totality of the vital spirits ; it is engendered in the brain by 

 "virtue of the powers of the proper material and form of the 

 brain," just as the vital soul is engendered by the substance of 

 the heart ; or as we should say in modern language, psychical 

 phenomena are the outcome of the activity of the nervous 

 tissues. And from the way in which he not once only but 

 repeatedly scoffs at the philosophers who deny to brute beasts 

 all the principal functions of the chief soul, though the brains 

 of these are so like that of man, we may infer that he nursed 

 in secret the belief that future inquiry would make clear the 

 hidden meaning of the complicated structure of the brain, and 

 shew how its several parts were concerned in the different 

 activities of the soul. But the time for that had not yet come. 

 Even the preliminary step, an adequate psychological analysis 

 of the faculties of the soul, was as in his opinion yet wanting ; 

 and he refused to waste his time in speculations, the conclusions 

 of which could not be tested either by anatomical observation 

 or by vivisectional experiment. He was clear that the soul 

 was engendered in and by the brain, but beyond that he knew 

 next to nothing. Vivisection taught him that when the brain 

 is removed, sensation and movement are lost ; but it taught him 

 little more than this. He was not to be led into a quarrel with 

 the Church, by indulging in speculations having no solid basis. 



17—2 



