I call it the “Bourbon Street Caper.” It didn’t happen to me, but the experience was so absorbing, as told by an acquaintance of mine, that I feel like it did. The scene was Mardi Gras in New Orleans, ...

The principle of direct reciprocity, or paying back specific individuals, is assumed to be a critical component of everyday social exchange and a key mechanism for the evolution of cooperation. Young ...

Tit for tat, do unto others, one good turn deserves another. These are only some of the familiar expressions which articulate the belief that reciprocity is a basic principle of social interactions.

The European Council is arguably one of the European Union’s (EU) most dynamic decision-making bodies. Both scholars and practitioners attribute its effectiveness to an informal norm of diffuse ...

Five-year-olds enforce reciprocal behavior in social interactions. A study shows that children come to recognize reciprocity as a norm between the ages of 3 and 5. Five-year-olds enforce reciprocal ...