424 THE BRAIN. 



in them. For while man is superior in general intelligence to all 

 the lower animals, he is inferior to many of them in the acuteness 

 of the special senses. 



As a general rule, also, the size of the cerebrum in different 

 races and in different individuals corresponds with the grade of 

 their intelligence. The size of the cranium, as compared with that 

 of the face, is smallest in the savage negro and Indian tribes ; larger 

 in the civilized or semi-civilized Chinese, Malay, Arab, and Japan- 

 ese ; while it is largest of all in the enlightened European races. 

 This difference in the development of the brain is not probably an 

 effect of long-continued civilization or otherwise ; but it is, on the 

 contrary, the superiority in cerebral development which makes 

 some races readily susceptible of civilization, while others are 

 either altogether incapable of it, or can only advance in it to a 

 certain limit. Although all races therefore may, perhaps, be said 

 to start from the same level of absolute ignorance, yet after the 

 lapse of a certain time one race will have advanced farther in 

 civilization than another, owing to a superior capacity for improve- 

 ment, dependent on original organization. 



The same thing is true with regard to different individuals. At 

 birth, all men are equally ignorant ; and yet at the end of a certain 

 period one will have acquired a very much greater intellectual 

 power than another, even under similar conditions of training, 

 education, &c. He has been able to accumulate more information 

 from the same sources, and to use the same experience to better 

 advantage than his associates ; and the result of this is a certain 

 intellectual superiority, which becomes still greater by its own 

 exercise. This superiority, it will be observed, lies not so much 

 in the power of perceiving external objects and events, and of re- 

 cognizing the connection between them, as in that of drawing con- 

 clusions from one fact to another, and of adapting to new combina- 

 tions the knowledge which has already been acquired. 



It is this particular kind of intellectual difference, existing in a 

 marked degree, between animals, races, and individuals, which cor- 

 responds with the difference in development of the cerebral hemi- 

 spheres. We have, therefore, evidence from three different sources 

 that the cerebral hemispheres are the seat of the reasoning powers, 

 or of the intellectual faculties proper. First, when these ganglia 

 are removed in the lower animals, the intellectual faculties are the 

 only ones which are lost. Secondly, injury to these ganglia, in the 

 human subject, is followed by a corresponding impairment of the 



