CREATION BY EVOLUTION 



inflicted by disease or injury upon certain parts of the brain 

 affects the mind in different ways, ranging widely from 

 purely sensory and motor changes, such as blindness or the 

 loss of the voluntary control of certain movements, to the 

 most profound interference with understanding and person- 

 ality. If, then, the manifestations of intelligence are in 

 some way linked to certain bodily structures, some at least 

 of which can be identified and examined, it becomes a mat- 

 ter of special interest to discover wherein the human brain 

 differs from that of other living creatures, between whose 

 intellectual powers and those of man there is so vast a 

 chasm. 



For more than a century anatomists have been making 

 detailed comparisons between the brains of men and those 

 of other creatures known as mammals, which resemble man- 

 kind in being provided with hair and with milk-producing 

 glands for feeding their infants. It was hoped in this way 

 to discover the secret of man's peculiar intellectual powers. 

 Although a common and very distinctive plan of architecture 

 is found in the brains of different mammals, an examination 

 of their size, form, and structural details reveals a wide 

 range of variation. The question arises whether it is pos- 

 sible to correlate these contrasts in the brain with the variant 

 capabilities of the respective animals and to discover any 

 outstanding distinctive features in the human brain that 

 are at all commensurate with man's intellectual supremacy. 

 A century ago, in order to explain what in those days were 

 termed the distinctive "faculties" of man's mind, investi- 

 gators plunged into this inquiry with the conviction that the 

 human brain must contain certain organs of structures pecu- 

 liar to itself. One anatomist after another put forward the 

 claim that he had found in a certain structure evidence to 

 substantiate man's intellectual preeminence, only to provoke 



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