198 BIOLOGICAL ASPECTS OF HUMAN PROBLEMS 



failure in education and self-control and dangerous 

 propinquity of the youth of opposite sexes. The 

 greatest of all checks to prostitution would result 

 from the growth of that refinement of feeling and 

 self-consciousness which would render clear to any 

 man the intense and degrading selfishness that does 

 not hesitate to damage the life of another individual 

 for the sake of personal sensuous gratification, and 

 this feeling will be the more strongly operative the 

 greater the respect for the ties of family life and the 

 greater the hope of those concerned in one day hav- 

 ing children. But such changes as these could come 

 only as part of a general elevation in the level of 

 intelligence and moral sensitiveness. 



IV 



The sex instincts do not always lead in the direc- 

 tion of excess. Indeed, the opposite tendency not 

 rarely asserts itself that is an avoidance of all 

 sexual relations in life. This may be due to a weakly 

 developed sex instinct (sometimes dependent on 

 poor health) or to the excessive distrust of a timid 

 or cold nature, or to intense absorption in an occu- 

 pation calling for a great output of mental or mus- 

 cular energy. In each case the effect is the same; 

 there is a failure on the part of the individual to 

 reproduce. There are two great privileges which 

 nature accords to every normal human being, the 

 privilege of self-development and the privilege of 



