Reciprocity is a pattern of mutually contingent exchange of gratifications, or tit for tat. Reciprocity can be shown to be one of the universal aspects of moral codes all around the world and has been argued to be key for social stability. Reciprocal social mores range from mutual gift exchange to rules of hospitality. As a normative concept, reciprocity typically focuses on an individual’s or an organization’s return of proportional or equivalent benefits for benefits bestowed by others. The return of harm for harm (which we usually call retribution) is the opposite side of the coin of reciprocity. In addition, it is important to note that, because its core element is an exchange, reciprocity is not synonymous with the Golden Rule (“do unto others as ...