Whereas rewards or sanctions by second parties can often be rationalized, or are at least likely to be colored, by egocentric, ''nonnormative'' motives, the rewards and sanctions of third parties reveal the truly normative standards of behavior. For instance, norm adherence may trigger feelings of gratitude if second parties benefit from the norm adherence in economic terms and this may, in turn, induce second parties to reward those who obey the norm. In this case, the rewarding by the second party cannot be taken as unambiguous evidence for an appreciated behavioral standard. Likewise, if norm violation directly harms someone, his impulse is to retaliate, but retaliation may have nothing to do with his appreciation of behavioral standards. The study of third-party rewards and sanctions can clarify these confounding factors.

DEFINE: Introduces the meaningful distinction between second-party and third-party reward/sanction as evidence for norm internalization.

Ernst Fehr, Third-Party Punishment and …, loc. 14