238 DOCTRINE OF EVOLUTION 



veloped cerebrum, whatever may be the ultimate nature 

 of the way mental processes are determined by physi- 

 cal processes, or vice versa. This fact stands unques- 

 tioned and unassailable ; human faculty and the brain 

 cannot be considered apart, even if they may not 

 actually be different aspects of the same basic " mind- _l 

 stuff," as Clifford calls the ultimate dual thing. ^ 



Like all of the other organs of lesser importance 

 belonging to the nervous system, the brain is a com- 

 plex of tissues which in the last analysis are groups of 

 cell-bodies with their fibrous prolongations. When these 

 cellular elements are in operation, mental processes 

 go on ; the. unit of the mental process therefore is the^ 

 functioning of a brain-cell. But we know that the 

 substance of a brain-cell is the wonderful physical basis 

 of life called protoplasm, that demanded our attention 

 at the outset. The chemicals that go to make up 

 protoplasm are everywhere carbon, hydrogen, oxygen, 

 and other substances that are exactly the same out- 

 side the body as inside. It is the combination of these 

 substances in a peculiar way which makes protoplasm, 

 and it is the combination of their individual properties 

 which in a real even though unknown manner gives 

 the powers to protoplasm, even to that of a living brain- 

 / cell. Does science teach us, then, that the ultimate 

 elements of human faculty are carbon-ness and hydro- 

 gen-ness, and oxygen-ness, which in themselves are not 

 mind, but which when they are combined, and when 

 such chemical atoms exist in protoplasm, constitute 

 mental powers ? Plain common-sense answers in,Jbhe 

 affirmative. We need not, indeed, we must not, attrib- 

 ute mind as such to rock salt or to the water of a 



