THE EVOLUTION OF MIND 365 



certain amount of mind somehow captured and attached to each 

 brain, human and brute ? Or is he and others of his kind miracu- 

 lously created out of nothing, when brains, including those of lower 

 animals, come into being and begin to function ? In any case the 

 player, if he exists, lies, if anything, even farther outside the range 

 of observation than even ' matter in itself.' We have no means of 

 knowing anything about him. All we know quite certainly is that 

 there is mind, and the mind tells us that it is associated with a 

 brain, and with expenditure of energy. To us mind is a function 

 of the brain. 



606. The physical characters of animals develop in response to 

 stimuli, in directions and within limits that have been closely fixed 

 by evolution. On that account the body of every normal man is 

 very like the body of every other normal individual of the same 

 variety. Thus the lungs and brain of one person are very like the 

 lungs and brain of any other. We attribute these likenesses to the 

 fact of a common descent. But, in spite of this common descent, 

 the mind of every man so develops as to be immensely different 

 from the mind of every other man, past or present. For example, 

 while my father acquired a knowledge of military science, my mind 

 has grown in such a way that I know more or less imperfectly 

 the art of medicine. My neighbour, the sailor, likes and dislikes 

 one lot of people ; I quite another lot. He is familiar with one set 

 of scenes ; I with quite other scenes. If we suddenly exchanged 

 bodies we should scarcely be conscious of the change till the mirror 

 or the behaviour of other people revealed it ; if we exchanged 

 minds we should be as lunatics in one another's environments. Had 

 I been captured as an infant by savages, and reared by them, I 

 should now resemble my educators mentally much more nearly 

 than my progenitors. For example, I should know only the 

 things that they know the scenes, the people, the aspirations. 

 Obviously then intellectual characters cannot have been evolved 

 in the same sense as physical characters. Thus, a knowledge of 

 medicine can never have been evolved in my case in the same 

 sense that brains have been evolved. How then does it happen 

 that I possess a knowledge of medicine? It seems to me, as the 

 only probable explanation, that mind is not a thing distinct from 

 the brain, but only the work of the brain just as manipulation is 

 the work of the hand. Nature has not directly evolved immaterial 

 minds any more than she has evolved manipulations. She has 

 merely evolved brains and hands capable of doing work useful to 

 the individual. The kind of brain she has evolved in the human 



