We have now traced the evolution of the marriage contract throughout its entire course, and are able to perceive in a measure its true place in the general history of the human family. Again the movement has been in a circle. As in the case of monogamy, the genesis of contract must be sought beyond the border-line between man and the lower animals. In the "natural history" stage of human existence marriage rested on the free consent of the man and the woman. It was an informal agreement. The man was the wooer, and to the woman belonged the first place in sexual choice. In obedience to the unvarying requirements of organic law, the best attributes of each race have thus been differentiated: through natural selection they represent the survival of the fittest. At a later stage of development the element of mutual consent falls somewhat into abeyance. With the rise of property, industry, and a more complex social organization, giving birth to new desires and ambitions, contract by the guardian in part supersedes self-betrothal. Purchase and its occasional alternative, capture, depriving woman of her natural right of assent, tend to reduce the wife to concubinage and domestic slavery. But fortunately the victory is not complete. Just as monogamy is never displaced by polygyny as the natural type of marriage, so the consent of woman as the normal condition of matrimonial union is never entirely destroyed by wife-purchase. With the evolution of altruism, the increase of culture, producing sympathy upon which connubial love largely depends, and the gradual recognition of the spiritual equality of the sexes, self-betrothal, like monogamy, again predominates. In short, whether regarded historically or biologically, monogamy and self-betrothal appear simply as two aspects of the same institution; they are connected by a psychic bond, and together they constitute the highest type of marriage and the family. CHAPTER V EARLY HISTORY OF DIVORCE