206 BIOLOGICAL ASPECTS OF HUMAN PROBLEMS 



any lapse in good habits of living, or any accident 

 which subjects the parents to the poisonous effects 

 of disease, becomes a hazard to the next generation, 

 and may place on it a mortgage of physical debility 

 or mental defect which can never be paid off. There- 

 fore, so to live as to secure for children, unimpaired, 

 the heritage which nature has made possible for them 

 should be accounted a prime virtue. On the other 

 hand, so to live, either through ignorance or self- 

 indulgence, as to betray the precious life trust reposed 

 by nature in every healthy man and woman is 

 always a profound misfortune and frequently, also, 

 a crime against humanity. 



