ABSTRACT
Reciprocity threatens to swallow up all social transactions. It is a fundamental concern, in the sense that its justification is given in terms of things necessary to moral agency as such. Primary goods are the things necessary for the life of a rational agent as such. Equilibrium, as defined here, is one of the primary goods, and it is linked to reciprocity. And since it is a deontic norm, reciprocity is fundamental in another sense. Everywhere, in every society of record, there is a norm of reciprocity about such things. Returns are expected, good for good received, hostility for hostility. There is an intricate etiquette for it all, and it is connected to prudence, self-interest, altruism, basic human needs, social welfare, notions of desert and duty, justice and fairness. Moral theory about the virtues begins with description: a description of the characteristic capacities, abilities, propensities, and activities of moral agents qua moral agents.
