232 READINGS IN BIOLOGICAL SCIENCE 



If they prefer to take the chance, which is at worst 3:1 in favor of be- 

 getting a normal child, I advise against further propagation if the first 

 child is normal. 



As regards serious sex-linked anomalies, as for instance haemophilia, I 

 think affected men should be strongly advised against propagation, since 

 their normal daughters are sure to transmit haemophilia to half their sons. 



HEREDITY AND ENVIRONMENT 



It cannot be denied that the estabhshment of the fundamental fact that 

 the genes are virtually unchangeable by external agencies is somewhat 

 disillusioning. All the valuable acquirements which conscientious parents 

 may accumulate in the course of life are genetically a dead investment. 

 Conversely, however, the same fact involves considerable consolation. 

 Neither are our evil acquirements visited upon our children genotypically. 

 Irrespective of the parent's dissipated manner of life the children may 

 nevertheless in genetic respect get a good start, this start only depending 

 upon the genes which the parental germ cells contained. 



It is quite another matter, however, that the evil acquirements of the 

 parents create a bad environment for the children. It is here that their 

 fatal consequences are to be sought. Alcoholism creates a bad environ- 

 ment, a bad milieu, for the children in almost every respect. Grave in- 

 fections in the parents may lead to contamination of the children. The 

 same holds true for moral dissipation. 



We finish as we started by emphasizing that each individual is a product 

 of two sets of influences, the genes on one hand, the environment on the 

 other. Valuable genes may in a bad environment be hampered in their 

 manifestation. Conversely, a good environment may in many cases counter- 

 act and eventually suppress the influence of undesirable genes, and effec- 

 tively accentuate the manifestation of the valuable genes. 



>>><-<-<■ 



THE ROLE OF EUGENICS * 



EDWIN GRANT CONKLIN 



Millions of human beings are born so defective in organization that they 

 cannot survive and leave offspring, and although we may attempt by every 

 means in our power to preserve them we cannot do it. Other millions not 

 so seriously defective we do manage to preserve, with the result that 

 modern society is burdened with multitudes of feeble-minded, epileptic, 

 insane, deaf, blind, and deformed, some of whom at least transmit these 

 defects to their children. It is because of the weakening of natural selection 



* Reprinted from Man, Real and Ideal by Edwin Grant Conklin, by permission of 

 Charles Scribner's Sons, Copyright 1943. 



