Westermark himself gives us a striking example. Since the most remote times the inhabitants of the Commune of Bats, composed of 3,300 persons, have intermarried; yet this population is very healthy and vigorous and shows no sign of degeneration. On the other hand, we have seen that contrasts produce a mutual attraction in the domain of love, while strong resemblances rather repel. Bernardin de St. Pierre has said that love is created by contrasts; the greater the contrast the greater the love. Schopenhauer remarks as follows: "Every individual seeks in the opposite sex peculiarities which contrast with his own; the most masculine man seeks the most feminine woman, while small and feeble men love large and strong women; people with short noses prefer long ones, tall and thin men prefer short and stout women. All this increases fecundity." Thus instinct is sufficient to protect humanity against consanguinity, each sex instinctively seeking the contrasts which consanguinity diminishes. SENTIMENT AND CALCULATION IN SEXUAL SELECTION Youth, beauty, health, finery and flirtation excite the sexual appetite. Many other sentiments are accessory, such as admiration, the pleasure of possession, respect, pity, etc. Inclination is an important element, but in no way necessary to sexual union. In the lower stages of human development, tenderness toward children is much stronger than sexual love. Among many savage races the love of a man for his wife is completely wanting, as well as that of the wife for her husband. In this case marriage depends on reciprocal convenience, on the desire to have children, and profits by personal comfort and the satisfaction of a purely animal sexual appetite. However, among these people the parents have a tender regard for their children. The husband has the right to beat his wife, but the wife is considered as unnatural or even criminal if she beats her children. Among the North American Indians, for example, conjugal love is, so to speak, unknown. On the other hand, in other savage races, such as the Touaregs, the Niam-Niams, the New Caledonians, the Tonganese and Australians, the conjoints have a deep affection for each other, and the husband often commits suicide on the death of his wife. On the whole, the sentiments of affection of the conjoints are the result of a long sexual life in common, and they are especially strengthened by the love of the parents for their children. As a rule, the mutual attachment of conjoints for each other among cultivated races is developed along with altruism. The tenderness and refinement of love as they exist at the present day among highly civilized races were unknown to most savages and to the older civilizations. In China it is considered good manners to beat the wife, and when a poor Chinaman treats his wife with consideration, it is to avoid having to buy another. What the Arab understands by love is only sexual appetite, and among the ancient Greeks it was nearly the same.