Reciprocity (social and political philosophy)

The social norm of reciprocity is the expectation that people will respond to each other in similar ways—responding to gifts and kindnesses from others with similar benevolence of their own, and responding to harmful, hurtful acts from others with either indifference or some form of retaliation. Such norms can be crude and mechanical, such as a literal reading of the eye-for-an-eye rule lex talionis, or they can be complex and sophisticated, such as a subtle understanding of how anonymous donations to an international organization can be a form of reciprocity for the receipt of very personal benefits, such as the love of a parent.

The norm of reciprocity varies widely in its details from situation to situation, and from society to society. Anthropologists and sociologists have often claimed, however, that having some version of the norm appears to be a social inevitability. Reciprocity figures prominently in social exchange theory,evolutionary psychology, social psychology,cultural anthropology and rational choice theory.

One-to-one reciprocity.Some reciprocal relationships are direct one-to-one arrangements between individuals, or between institutions, or between governments. Some of these are one-time arrangements, and others are embedded in long-term relationships. Families often have expectations that children will reciprocate for the care they receive as infants by caring for their elderly parents; businesses may have long-term contractual obligations with each other: governments make treaties with each other.

There are also one-to-one reciprocal relationships that are indirect. For example, there are sometimes long chains of exchanges, in which A gives a benefit to B, who passes on a similar benefit to C, and so on, in which each party in the chain expects that what goes around will eventually come back around. The classic anthropological example is the Kula exchange in the Trobriand Islands.

One-to-many and many-to-one reciprocity often lies somewhere between direct reciprocal arrangements and generalized reciprocity. Informal clubs in which the hosting arrangements circulate among members are examples of the one-to-many variety. Bridal showers are examples of the many-to-one variety. So are barn raising practices in some frontier communities. All of these are similar to direct reciprocity, since the beneficiaries are identified as such in each case, and contributors know exactly what they can expect in return. But because membership in the group changes, and needs for new meetings or marriages or barns are not always predictable, these cases differ significantly from precisely defined one-to-one cases.

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