However it may be, if we condense, by classification, all the notions that have been collected in relation to kinship by classes among the Australians, the Tamils, the primitive Mongols, the Mongoloids of North America and those of Polynesia, we may retrace the evolution of kinship by classes with sufficient appearance of truth.
To begin with, there must have existed hordes, which, though doubtless human, were still very bestial as regards their instincts and intelligence. In these hordes, which were not very numerous, the women being taken possession of by the most robust old males, the young ones were obliged either to quit the group or to remain in it by ravishing one or two women from rival hordes; for exogamy was a necessity. The least advanced of the Australian tribes seem to be still in this primitive stage. At length a little order was put into this disorder by the horde breaking up into clans; it was then decided that all the men and all the women of each clan should be brothers and sisters, and should not intermarry, and that on the other hand, all the men of a clan should be the husbands of all the women of the neighbouring clan, simply by right of birth. The Kamilaroi of Australia may represent the second stage.
In Polynesia the principle is the same, but the idea has become restricted and defined. Groups of real brothers marry groups of women actually sisters, thus forming households at once polyandric and polygamic; but traces of the antique marriage by fictitious groups of brothers and sisters appear again in the terms used to designate the various degrees of kinship. These terms are in reality purely classificatory, and take little account of real consanguinity.
Among the Redskins a new and important restriction has been established. Marriage outside the clan is continued, but not marriage by groups of sisters and brothers. That this was done in primitive times, however, is proved by the familial vocabulary. On the other hand, they have clearly renounced polyandry, and adopted polygamy with not less clearness; but this polygamy is special, and it is generally a group of sisters who marry the polygamous husband.
As for the terms of kinship, they are always general and classificatory. The relations are denominated by groups, and the titles of kinship do not in the least correspond to the ties of blood.
Lastly, among certain nomad Mongols of Asia, the strict prohibition to marry within the clan, and the terms of kinship applying to groups, show that formerly a familial system, analogous to that of the American Redskins, has been in use.
Moreover, this classificatory system is preserved entire in the denominations of kinship by the Tamils of India. But among these last, and also among certain Mongol populations of Thibetan Himalaya, the primitive family, at once polygamic and polyandric, that of the Hawaian islanders, has evolved after its own manner, which it is interesting to notice.
The Polynesian, or rather the Hawaian family, formed essentially by the conjugal union of a group of brothers with a group of sisters, may evidently be restricted in two ways. Either, in the long run, polyandry is found irksome; the men will no longer share their wives, even with brothers, but find polygamy very convenient; in this case the brothers contract isolated marriages, preserving nothing of the old ways but the custom of marrying, when possible, a group of sisters: the Redskins have done and still do this. Or, on the contrary, for one reason or another, and most often on account of the relative scarcity of women, the Hawaian marriage evolves in another direction. The brothers continue to marry in a group; but, instead of marrying simultaneously several sisters, they take only one wife and possess her in common: this time it is in the direction of polyandry that primitive group-marriage has evolved. From the Himalaya to Ceylon we find a long track of ethnic groups who have thus transformed their marriage. The mountaineers of Bhootan, the Naïrs, certain other aboriginal tribes of India, and a part of the population of Ceylon, where the Tamils have largely immigrated, are all of them the remains or landmarks of an ancient layer of polyandric population traversing the whole of Hindostan.
All these facts can be classed in a satisfactory manner. Thus united, and placed in a series, they complete and throw a light on each other, and show us the reason of customs which before appeared inexplicable.
All this evolution is quite admissible, but it is important to restrict it to the populations with which it actually appears to be connected, and not to make of it a universal law, applicable to the whole human race.