Section II, 1919 [9] Trans. R.S.C. 



The Revolt Against Reason; a Contribution to the History of Thought 



By G. S. Brett, M.A. (Oxon.), F.R.S.C. 

 (Read May Meeting, 1919) 



I 



There is a curious passage in the history of Descartes' mind 

 which deserves to be studied for the light it throws on the development 

 of thought at that critical point. The passage in question relates to 

 the notion that animals are machines, a very natural and sensible idea 

 if rightly understood; since Huxley has taken it under his protection 

 we need not labour the point but give a brief account of Descartes' 

 own views and then indicate the real importance which belongs to 

 the topic. 



It had been customary from the time of Aristotle to distinguish 

 three senses of the word soul and three grades of being, namely, 

 plants, animals, men. Since Descartes proposed to confine the term 

 soul to the Reason, the question whether animals have souls can only 

 be taken to mean, have animals a rational soul? As Descartes , had 

 also declared the human body to be a machine, and everyone agreed 

 that man was a rational animal, the most elementary logic could 

 show that an animal was wholly what man was in part, to wit a body 

 and therefore a machine. So far the point is clear, but Descartes 

 was not quite sure what his own statements meant. At first he was 

 content to treat animals as machines; he was at that time fresh from 

 the pursuit of physiology and also very much inclined to regard 

 machinery as the true type of self-explanatory causation. In his 

 eagerness to be rid of all occult causes he was ready to disregard some 

 obvious facts. At this period he could see no distinction between a 

 sound organism and a perfect clock. But as time went on these 

 impulses grew weaker. The force of analogy began to assert itself. 

 He hinted at the possibility of a different principle, the instinct. 

 While he began by speaking of animals as mere machines he ended 

 with the much more moderate statement that it was not possible to 

 prove they could think. In the interval between his earliest and his 

 latest views he grants that these organisms may have sensations and a 

 kind of consciousness which does not amount to thought. In general 

 his position is that Reason in the proper sense is peculiar to the human 

 mind. In human life there are many actions that do not come into 

 consciousness; they are reflex activities which the organism carries 

 out without the intervention of mind. These are operations of our 



