THE MIND OF THE IDIOT 425 



believe. But the fact that human acquirements, especially mental 

 acquirements, are of immensely greater magnitude and importance 

 than is commonly supposed cannot, I believe, be doubted. 



699. A little thought renders it evident that the essential defect 

 of the feeble-minded person, the idiot, and the imbecile, is lack of 

 memory. 1 He is unable to profit like the normal individual from 

 experience. This defect of memory may be, and usually is, general, 

 so that the individual is able to learn very little. Or the defect 

 may be limited to some particular ; for example the individual 

 may be unable to acquire the code of morals prevalent in the 

 community in which he exists an acquirement which on the 

 average and in the long run would be of great advantage to him. 

 The truth that the higher intellectual faculties are less developed 

 in the feeble-minded than lower faculties is due entirely to the fact 

 that the former can be acquired only by people whose receptive 

 powers are considerable. In effect and in fact the feeble-minded 

 person is an instance of reversion to a pre-human mental state. 

 Judged by the human standard every dog and monkey is an 

 imbecile. But the reversion of the imbecile is not complete ; for, 

 while he has lost part of his power of profiting by experience, he has 

 regained no part of the lost power of being guided by instinct. 

 Therefore he is correspondingly helpless as compared to a lower 

 animal. On the other hand, the instincts (e.g. the sexual) which 

 normal human beings still possess often appear unduly prominent 

 in him ; but only because he cannot learn to control them. 



700. But though human beings develop mainly under the 

 stimulus of use and experience, doubtless they differ * by nature ' 

 amongst themselves just as much as animals that develop solely 

 under the stimulus of nutriment. In the last analysis all variations 

 are nothing other than variations in powers of responding to 

 stimuli nutriment, use, and injury and we have no reason to 

 suppose that variations in the capacities for responding to the 

 stimulus of use are smaller or fewer than variations in the capacity 

 for responding to the stimulus of nutriment or injury. Doubtless, 

 therefore, men vary not only in general mental capacity (i.e. power 

 of making mental acquirements) but also in particular departments 

 of capacity. At the one extreme is the absolute idiot who has no 

 power of storing and utilizing experiences, and, at the other, the 

 genius who has exceptionally great powers. It has been observed 

 that some imbeciles have considerable capacity in some particular 

 department. Thus, they may have great powers of remembering 



1 See 762 et seq. 



