"Monogamy has a sentimental basis which is quite distinct from the political one of equal numbers of the sexes. Equal numbers in the sexes are quite compatible with a change of partners every day or every hour. Physically there is nothing to distinguish human society from the farm-yard except that children are more troublesome and costly than chickens and calves, and that men and women are not so completely enslaved as farm stock. Accordingly, the people whose conception of marriage is a farm-yard or slave-quarter conception are always more or less in a panic lest the slightest relaxation of the marriage laws should utterly demoralize society; whilst those to whom marriage is a matter of more highly evolved sentiments and needs (sometimes said to be distinctively human, though birds and animals in a state of freedom evince them quite as touchingly as we) are much more liberal, knowing as they do that monogamy will take care of itself provided the parties are free enough, and that promiscuity is a product of slavery and not of liberty."