52 MARRIAGE AND DISEASE. 



has gained no fixity, and, the mother not belonging to 

 the same variety, the offspring " throws back " to the 

 original. Even had the mother possessed something 

 of this mental quality, the result would probably have 

 been the same (though the chances of reversion would 

 have been lessened), for the reason that the stride from 

 the average mental development to that of the mathe- 

 matical genius is too great for Nature. Had the father's 

 peculiar mental character been less marked, and more 

 especially had it been the outcome of many generations 

 of building up, as it is in the case of the Jew, there 

 would have been very little tendency to reversion, and 

 the children would almost certainly have inherited it. 

 In the Jew the character has become fixed ; by repeated 

 transmission through generations it has become a stable 

 and constant family character, and even if the Jew 

 were to marry a woman belonging to a different variety, 

 yet would the children inherit the character. This 

 mental character has been so ingrained in the Jew by 

 continual cultivation, and by intermarriage with those 

 of his own race, nearly all of whom cultivate the char- 

 acter, that it would take many " crossings " to efface 

 it ; whereas the same character, even in a much higher 

 degree of development, as it occurs sometimes in the 

 great financiers of other races, is but the outcome of 

 some happy combination of parental characters, and 

 having no stability, we look in vain for its continuance 

 in the offspring. 



A point of still greater importance to us, is the fact 

 that this principle of reversion to the normal is as 



