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 personality. 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 matter 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 mankind 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 possible 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, investigators plunged into this inquiry with the conviction that the human brain must contain certain organs of structures peculiar 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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