The fact that the anthropoid apes produce feeble and dependent young, whose infancy is long, has probably been the origin of marriage. Kautsky says that in primitive man the child belongs to the clan; but this is an error. Originally, human societies were composed of families, or rather associations of families. In primitive man, these families play the fundamental role and constitute the nucleus of society. In the anthropoid ape we already find the family, but not the clan. This must also have been the case with the pithecanthropoids and other extinct transitory forms. In fact, the lowest savages still live as isolated families like the carnivorous mammals, rather than in clans or tribes. This is the case, for example, with the Weddas of Ceylon, the indigenes of Terra del Fuego, the aboriginal Australians, the Esquimaux and certain Indians of Brazil. In this way they have better conditions for subsistence. In primitive times therefore, man lived in families, on the produce of the chase. Later on, the spirit of discovery, the more abundant food obtained by traps and by the cultivation of plants allowed men to live in tribes. Thus, intellectual development was the first cause of social life in man, and Lubbock is certainly wrong in considering that the establishment of clans dates further back than the first beginning of civilization. Westermark's conclusions are as follows: (1). _At no period of human existence has family life been replaced by clan life._ (2). _Conjugal life is a heritage from ancestors who lived in a similar way to the anthropoid apes of the present day._ (3). _Although less intimately and less constantly bound to the children than to the mother, the father has always been in man the protector of the family._ CRITICISM OF THE DOCTRINE OF PROMISCUITY Most sociologists believe with Lubbock, Bachofen, MacLennan, Bastian, Giraud-Teulon, Wilkens, and others that primitive man lived in sexual promiscuity. If we agree with Westermark that the term marriage includes polygamy, polyandry and limited marriage, the opinion of these authors is wrong. What they have considered as promiscuity can always be included in one of these forms of marriage, even among the indigenes of Hayti, whose life is the most debauched. The author who has most confused the question is Fison, with his dogmatic theories concerning the Australians. Obliged to admit that promiscuity does not exist among these people, he still maintains that it existed formerly. Curr, who was better acquainted than Fison with the Australians, has proved that they are normally monogamous.