§ 209
The duty of marriage is the procreation of healthy children. The privilege and pleasure of marriage is what Havelock Ellis has called the play side of love.
If the husband does not secure and by a superior knowledge of love insist on securing in his wife this essential of human marriage, his marriage is only legal, only social, and has no love instinct back of it. It is not an erotic union. Erotic unions are the only healthy ones.
Erotic unions are the only healthy ones not merely in the sense of health-giving to the partners, but also in the sense of having themselves a healthy growth in progressively embracing all human activities, in which the partners are concerned in egoistic and social lines, embracing them in such a way that the love instinct increases its control over the ego instinct. This increase is the real object of a love marriage, not increase of wealth, honour, distinction, and experience of the world but increase of the dominance of love over self.