The anthropologist Marcel Mauss, in his famous exploration of the gift in "primitive" and archaic societies, showed that the essential aspect of the exchange of presents involved the establishment of a social tie that bound the parties together above and beyond any material value of the objects exchanged. He argued that these intangible mutual "debts" constituted the social fabric. Godbout and Caille show that, contrary to the modern assumption that societies function on the basis of market exchange and the pursuit of self-interest, the gift still constitutes the foundation of our social...