44 FOKMS OF MENTAL DEFECT AND DERANGEMENT. 



intelligence, between mere slight imbecility, marked by in- 

 capacity for education or self-support, and obvious idiocy 

 (amentia) ; the intermediate conditions comprising what is 

 known in man as fatuity, feebleness of intellect or mind 

 (dementia), and such animals as are equivalent to what among 

 men are denominated simpletons, fools, or naturals. 



In its extreme form or degree idiocy (amentia), that is, 

 an original and absolute or complete absence of mind, if such 

 a thing ever really exists compatibly with life either in man 

 or other animals, is rarely observed or studied among the 

 lower animals, simply because whenever it becomes evident 

 that a domestic animal is so far defective either in bodily or 

 mental power as to be useless or burdensome to man, its life 

 is ruthlessly and thoughtlessly sacrificed. We are as yet 

 apparently far from that stage of civilisation, of humanity, 

 and of common sense which will lead us to collect insane ani- 

 mals, as we do insane men, in hospitals, and so provide means 

 for the scientific study of the various forms of animal insanity 

 and their relative curability. What is called idiocy in ani- 

 mals is usually merely one of the minor forms of mental 

 imbecility, some of which minor forms or degrees may show 

 themselves simply as want of character, for instance in the 

 cat (Browne). Thus Pierquin speaks of partial idiocy and 

 incomplete dementia. Darwin refers to semt-idiocy in a dog, 

 and describes its ' senseless habit ' of rotation or gyration, a 

 common phenomenon of insanity in that animal. 



This mental imbecility, which includes all forms or de- 

 grees of partial want of mind or intelligence, is of great 

 practical interest in connection with the incapacity for being 

 trained or trusted that characterises animals which are its 

 subjects, and with their responsibility and punishment for 

 mistakes or misdemeanours. There is a non-intelligence, a 

 normal stupidity which the poor animal cannot help, because 

 it is the natural outcome of imperfect or arrested develop- 

 ment of brain, which again is frequently the mere concomi- 

 tant of defective development of the general nervous system, 

 or of the general bodily organisation. Pierquin observes 

 that the various degrees of mental imbecility including 

 idiocy in the horse are usually accompaniments of small 



