PHYSIOLOGY AND PSYCHOLOGY. 17 



England, who spoko English fluently, but who, receiving a blow on 

 the head, during his illness was able to answer questions only in 

 French. 



So with Imagination. We find that imagination differs from 

 sensation in little but the recalling of past impressions, either in tlie 

 same order, or in a different order, from that in which they appeared 

 when actually pi-esent to the senses; so that with regard to the 

 imagination it is not necessary to recapitulate the reasons indicated 

 for the conviction that the pictures recalled depend as much upon 

 action of the nerves and other bodily functions, as do the contents 

 of the faculty, so called, of memory. 



The moral sphere cannot be here considered at length. But this 

 statement may be advisedly made, that the constituents of our moral 

 being depend almost entirely upon our bodily organism. One in- 

 stance only will be given of the influence of bodily changes upon the 

 moral character and conduct of an individual. It is that of an 

 officer in the United States army, who during the late war was noted 

 for his dash and bravery in many battles, but who, being once 

 knocked down by the concussion produced by a cannon ball, became 

 from that hour as noted for cowardice as he had formerly been for 

 bravery, and could never again be induced to go into a battle, or to 

 resume his militaiy career. 



The question under consideration has assumed increased import- 

 ance in connection with the comparatively-new, but firmly-established 

 doctrine of Heredity. This doctrine assumes the fact of the trans- 

 mission from generation to generation of both mental and physical 

 tendencies, and of these in conjunction with, and dependent upon, 

 one another, handed down through a progi*essive development of the 

 nervous system. To understand the possibility of improvement from 

 age to age, we must understand, in its "subtle materialism," this 

 principle which makes transmission possible, this principle which 

 plays upon the nerves of men, and makes them its instrument for 

 the storing-up of power for future use, accumulation and develop- 

 ment. It is this which makes possible the growth of civilization 

 from age to age, which explains that element of good or evil in 

 man, which no surroundings, no education, can entirely eradicate or 

 overcome. It is thus that the sins of the fathers are visited upon 

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