678 THE POPULAR SCIENCE MONTHLY. 



by luxury, corruption, and other enervating vices, that it undergoes 

 that degeneration of character which prepares and makes easy its over- 

 throw. In like manner a family, reckless of the laws of physical and 

 moral hygiene, may go through a process of degeneracy until it becomes 

 extinct. It was no mere dream of prophetic frenzy that when the 

 fathers have eaten sour grapes the children's teeth are set on edge, nor 

 was it a meaningless menace that the sins of the fathers shall be visited 

 upon the children unto the third and fourth generations ; it was an 

 actual insight into the natural law by which degeneracy increases 

 through generations by which one generation reaps the wrong which 

 its fathers have sown, as its children in turn will reap the wrong which 

 it has sown. What we call insanity or mental derangement is truly, 

 in most cases, a form of human degeneracy, a phase in the working out 

 of it ; and, if we were to suffer this degeneracy to take its course 

 unchecked through generations, the natural termination would be sterile 

 idiocy and extinction of the family. A curious despot would find it 

 impossible, were he to make the experiment, to breed and propagate a 

 race of insane people ; Nature, unwilling to continue a morbid variety 

 of the human kind, would bring his experiment to an end by the pro- 

 duction of sterile idiocy. If man will but make himself the subject of 

 serious scientific study, he shall find that this working out of degeneracy 

 through generations affords him a rational explanation of most of those 

 evil impulses of the heart which he has been content to attribute to 

 the wiles and instigations of the devil ; that the evil sjDirit which has 

 taken possession of the wicked man is often the legacy of parental or 

 ancestral error, misfortune, or wrong-doing. Let me illustrate by an 

 example the nature and bearing of this scientific study. 



I will take for this purpose a case which every physician who has 

 had much experience must have been asked some time or other to 

 consider and advise about : a quite young child, which is causing its 

 parents alarm and distress by the precocious display of vicious desires 

 and tendencies of all sorts, that are quite out of keeping with its 

 tender years, and by the utter failure of either precept, or example, or 

 punishment to imbue it with good feeling and with the desire to do 

 right. It may not be notably deficient in intelligence ; on the con- 

 trary, it may be capable of learning quickly when it likes, and 

 extremely cunning in lying, in stealing, in gratifying other perverse 

 inclinations ; and it can not be said not to know right from wrong, 

 since it invariably eschews the right and chooses the wrong, showing 

 an amazing acuteness in escaping detection and the punishment which 

 follows detection. It is, in truth, congenitally conscienceless, by 

 nature destitute of moral sense and actively imbued with an immoral 

 sense. Now, this unfortunate creature is of so tender an age that the 

 theory of satanic agency is not thought to offer an adequate explana- 

 tion of its evil impulses ; in the end everybody who has to do with it 

 feels that it is not responsible for its vicious conduct, perceives that 



