In the second part of his essay, Sahlins shows that mutuality of being is a symbolic notion of belonging, not a biological connection by “blood.†Quite apart from relations of birth, people may become kin in ways ranging from sharing the same name or the same food to helping each other survive the perils of the high seas. In a groundbreaking argument, he demonstrates that even where kinship is reckoned from births, it is because the wider kindred or the clan ancestors are already involved in procreation, so that the notion of birth is meaningfully dependent on kinship rather than kinship on birth. By formulating this reversal, Sahlins identifies what kinship truly is: not nature, but culture.