One common life was held to run through all the members of the tribe and all the domestic animals of the species which was its principal means of support.

In the totem or hunting stage the clan had necessarily been small, because a large collection of persons could not subsist together by hunting and the consumption of roots and fruits.

When an additional means of support was afforded by the domestication of an important animal, a much larger number of persons could live together, and apparently several clans became amalgamated into a tribe.

The sanctity of the domestic animals was much greater than that of the totem because they lived with man and partook of his food, which was the strongest tie of kinship; and since he still endowed them with self-consciousness and volition, he thought they had come voluntarily to aid him in sustaining life.

Both on this account and for fear of injuring the common life they were not usually killed.