Digest of terms

reciprocity

recognition between two or more individuals of the importance of mutually equal treatment. This may be positive ('one good turn deserves another'), or negative ('an eye for an eye, a tooth for a tooth'). It is fundamental to ideas of equality, fairness, and justice, and related to, if indeed it does not underlie, the Golden Rule. In evolutionary theory it is recognized as having played an important role in the development of altruism, albeit in the relatively limited form of 'reciprocal altruism' - 'you scratch my back and I'll scratch yours'. Without it much morality collapses. Ethical egoists, though, would argue that unless there is reciprocity there is no obligation to be moral to others, a view that altruists would reject as reducing morality to prudence in the negative sense.