60 MARRIAGE AND DISEASE. 



the person who has actually been insane may in some 

 cases marry with far less risk to the children than 

 many other persons who have never been so. For 

 example, the man whose grandfather and father have 

 been insane, would stand a much greater chance of 

 begetting children who would become insane, although 

 he had never shown a symptom of mental disorder 

 himself, than the man with a really good family 

 history whose mind had given way under pressure 

 of some extraordinary trial, mental or physical, and 

 who was some time recovered. In the first case the 

 character has gained prepotency from repeated trans- 

 mission, and even with a perfectly healthy wife, the 

 chance of reversion is not nearly so great as in the 

 second, where the character being recently acquired 

 and having no fixity will probably disappear, more 

 especially if the wife be healthy, and the exceptional 

 state of environment which developed the character 

 be removed. 



Fortunately, there are very few diseased conditions 

 in which we can cite instances of prepotency, as these 

 pathological variations, when continued, soon reach 

 the necessary fatal type and put an end to the family. 

 For this reason hereditary disease is seldom sufficiently 

 firmly fixed as to be able to resist the natural tendency 

 to reversion to the healthy type, if opportunity be 

 offered by marriage with the healthy. And for the 

 same reason it is rarely, even in the most deeply 

 tainted families, that we find the pathological family 

 character reproduced in all the children. In some 



