The passage from what is commonly termed savagery through barbarism to civilisation is marked by a change in the character of the associations which are almost everywhere a feature of human society. In the lower stages of culture, save among peoples whose organisation has perished under the pressure of foreign invasion or other external influences, man is found grouped into totem kins, intermarrying classes and similar organised bodies, and one of their most important characteristics is that membership of them depends on birth, not on the choice of the individual. In modern society, on the other hand, associations of this sort have entirely disappeared and man is grouped in voluntary societies, membership of which depends on his own choice.

It is true that the family, which exists in the lower stages of culture, though it is overshadowed by the other social phenomena, has persisted through all the manifold revolutions of society; especially in the stage of barbarism, its importance in some directions, such as the regulation of marriage, often forbidden within limits of consanguinity much wider than among ourselves, approaches the influence of the forms of natal association which it had supplanted. In the present day, however, if we set aside its economic and steadily diminishing ethical sides, it cannot be compared in importance with the territorial groupings on which state and municipal activities depend.