nic point of view should lead every individual to make as good a
choice as possible.

If a eugenically bad mating has been made, society should minimize as
far as possible the injurious results, by means of provision for
properly restricted divorce.

Consanguineous marriages in a degree no closer than that of first
cousins, are neither to be condemned nor praised indiscriminately. Their
desirability depends on the ancestry of the two persons involved; each
case should therefore be treated on its own merits.

CHAPTER XI

THE IMPROVEMENT OF SEXUAL SELECTION

"Love is blind" and "Marriage is a lottery," in the opinion of
proverbial lore. But as usual the proverbs do not tell the whole truth.
Mating is not wholly a matter of chance; there is and always has been a
considerable amount of selection involved. This selection must of course
be with respect to individual traits, a man or woman being for this
purpose merely the sum of his or her traits. Reflection will show that
with respect to any given trait there are three ways of mating: random,
assortative and preferential.

1. Random mating is described by J. Arthur Harris[95] as follows:

"Suppose a most highly refined socialistic community should set about to
equalize as nearly as possible not only men's labor and their
recompense, but the quality of their wives. It would never do to allow
individuals to select their own partners--superior cunning might result
in some having mates above the average desirability, which would be
socially unfair!

"The method adopted would be to write the names of an equal number of
men and women officially condemned to matrimony on cards, and to place
those for men in one lottery wheel and those for women in another. The
drawing of a pair of cards, one from each wheel, would then replace the
'present wasteful system' of 'competitive' courtship. If the cards were
thoroughly shuffled and the drawings perfectly at random, we should
expect only chance resemblances between husband and wife for age,
stature, eye and hair color, temper and so on; in the long run, a wife
would resemble her husband no more than the husband of some other
woman. In this case, the mathematician can give us a coefficient of
resemblance, or of assortative mating, which we write as zero. The other
extreme would be the state of affairs in which men of a certain type
(that is to say men differing from the general average by a definite
amount) always chose wi