What is eugenics? / by Leonard Darwin.

  • Leonard Darwin
Date:
1932
Catalogue details

Licence: Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0)

Credit: What is eugenics? / by Leonard Darwin. Source: Wellcome Collection.

    96/100 (page 86)
    86 WHAT IS EUGElSnCS? impossible to force high ideals into low minds. A person who is markedly inferior in mind will generally prefer to marry another person of like inferiority. Amongst such as these we can do little towards preventing parenthood, either by example or precept. Definite steps, such as those described in Chapter XIV, ought to be taken to reduce the size of the families of those of inferior stock. If this is not done, merely to preach care in marriage will do little towards saving the race. Turning to a different point, when a person has grounds for fearing that insanity, for example, may appear in his children, he is often advised to avoid marriage with any one similarly threatened. Now, it is true that the child who gets a double dose, so to speak, of harmful heredity, one from the father and one from the mother, is more than twice as likely in consequence to be cursed with the threatened evil. It is, therefore, worldly wisdom to avoid a marriage with a person similarly threatened. But let there be no mistake as to what is being done. A harmful inheritance is not destroyed by marriage with good stock. It is in consequence merely more often concealed and made to become more widely scattered. If it does not show itself, it will nevertheless lie hidden, but ready to come out in any future generation. The same principle applies to the marriages of cousins. They are only harmful if the stock common to both parents is bad. When both stocks are good, children of such marriages will have a double chance of turning out well. If the stock on both sides is bad, the children of cousin marriages will be likely to show the evil qualities common to the ancestors on both sides. This is true even if neither of the parents shows any visible defects ; for such defects may lie completely hidden. Marriages between cousins are, therefore, open to objection as regards immediate results. As regards the effects on the race, to marry a cousin is no worse than marrying anyone else. It would not increase the evil inheritance, though it might bring it to light, and conse¬ quently make it more easily stamped out. The immediate effects of cousin marriages may be very harmful, whilst the