Reciprocity is one of the main basic social relations that constitute societies. It consists of being favourable to others because others are favourable to you (and not from an exchange in the strict sense). It rests on three possible rationales: (1) balance (comparison, matching), often related...

Good social relations have more or less an aspect of gift-giving which, by nature, can be neither bought nor imposed. Interaction in this respect will lead purely selfish people to an irremediably inferior state, while pure altruism and unconditional morality are very demanding on the ground of...