148 HEREDITY AND EUGENICS 



the complexit}^ of the result. What we call human 

 character in its developed form appears to consist 

 in the acquired habit of inhibiting certain inherited 

 tendencies, and giving free expression to others. 

 But then, again, differences in powers of inhibition 

 are undoubtedly inherited, and weakness in such 

 powers ma}^ lead in the one extreme to vicious 

 tendencies, and in the other to a free expression of 

 the other elements of the inheritance. Nevertheless, 

 there is always a choice of ideals to be aimed at, 

 and it is necessary to distinguish in conduct between 

 those who fail to reach their ideals and those who 

 deliberately pursue non-moral ends. 



The lay mind frequently goes astray on the question 

 of the inheritance of abilit}^ by assuming that if the 

 sons of an able father do not themselves show ability, 

 this is a case of " failure of inheritance." In a 

 scientific view of inheritance in such a case, one of 

 the alternative factors has been inherited instead of 

 that which conditions ability — an undesirable instead 

 of a desirable quality has been handed on — or at 

 least one of the necessary elements for the expression 

 of abilit}' is missing. In types of ability where the 

 correlated action of several independent qualities 

 or factors is required, the appearance of the same 

 combination of exceptional qualities in the offspring is 

 very likely to be infrequent, because of the presence 

 of alternative characters in the germ plasm. 



That the tendency to perform certain tricks when 

 in a particular frame of mind may be inherited, was 

 show^n in a case cited by Darwin {Animals and Plants, 

 chap, xii.) of a man who, as a bo}^, had the habit, 

 when pleased, " of rapidly moving his fingers parallel 

 to each other, and, when much excited, of raising 

 both hands, with the fingers still moving, to the sides 

 of his face on a level with the eyes." As a grown 

 man the trick was with difficulty suppressed, but one 



