THE CEREBRUM, AND ITS FUNCTIONS. 817 



involves (as has been repeatedly shown) a change of structure; and the formation 

 of the newly generated tissue receives such an influence from the conditions under 

 which it originates, that all its subsequent activity displays their impress. This 

 view, indeed, must be extended to that remarkable hereditary transmission of 

 psychical character, which presents itself under circumstances that entirely forbid 

 our attributing it to any agency that can operate subsequently to birth, and which 

 it would seem impossible to account for on any other hypothesis than that the 

 formative capacity of the germ determines the subsequent development of the 

 Brain, as of other parts of the body, and (through this) its mode of activity, in 

 accordance with the influences under which that germ was first impregnated. And 

 thus what we speak of as the " original constitution" of each individual, is in 

 great part (if not entirely) determined by the conditions, dynamical and material, 

 of the parent-organisms ; a convincing proof of which general fact is afforded by 

 a careful examination of the parental constitution and habits, in a large propor- 

 tion of cases of Idiocy. 1 Whatever may be the congenital constitution, how- 

 ever, there can be no question that this is liable to great modification from ex- 

 ternal influences, both such as directly affect its physical conditions, and such 

 as operate through the consciousness, in determining the course of thought and 

 feeling, before the individual has acquired any self-determining power. Of this 

 influence of physical agencies, we have a typical example in the phenomena of 

 Cretinism ; since, although the conditions under which that state is developed 

 have not yet been precisely determined, no one can reasonably doubt that they 

 are such as act in the first instance in modifying the nutrition and activity of 

 the bodily organism in general, and of the Nervous system in particular. 



839. From the time when the Human being first becomes conscious that he 

 has a power within himself of determining the succession of his mental states, 

 from that time does he begin to be a free agent ; and in proportion as he exerts 

 that power, does he emancipate himself from the domination of his constitutional 

 or automatic tendencies. It is a principle now recognized by all the most enlight- 

 ened educators, that the development of this power of self-control ought to be 

 the object of all nursery discipline j and the process of its acquirement is very 

 gradual. When an infant is excited to a fit of passion by some unpleasant sen- 

 sation, its nurse attempts to restore its equanimity by presenting some new 

 object to its attention, so that the more recent and vivid pleasurable impression 

 may efface the sense of past uneasiness. As the infant grows into childhood, 

 the judicious parent no longer trusts to mere sensory impressions for the diver- 

 sion of the passionate excitement, but calls up in its mind such ideas and feel- 

 ings as it is capable of appreciating, and endeavors to keep the attention fixed 

 upon these, until the violence of the emotion has subsided ; and recourse is had 

 to the same process, whenever it is desired to check any tendency to action 

 which depends upon the selfish propensities appeal being always made to the 

 highest motives which the child is capable of recognizing, and punishment being 

 only had recourse to for the purpose of supplying an additional set of motives 

 when all others fail. For a time, this process of external suggestion may need 

 to be continually repeated, where there are strong impulses whose unworthy 

 character calls for repression ; but if it be judiciously adapted and consistently 

 persevered in, a very slight suggestion serves to recall the superior motives to 

 the conflict. And in further space, the child comes to feel that he has himself 

 the power of recalling them, and of controlling his urgent impulses to immediate 

 action. The power of self-control, thus usually acquired in the first instance 



A most valuable collection of data on this subject is afforded by Dr. Howe's admirable 

 tort 



ined 

 52 



"Report on Idiocy" made to the Legislature of Massachusetts, of which an abstract is 

 contained in the "American Journal of the Medical Sciences," April, 1849. 



