Topic summary
Social choice function
Extracted from the Wikipedia article Social welfare function.
Harsanyi's theorem
Introducing one additional axiom—the nonexistence of Dutch Books, or equivalently that social choice behaves according to the axioms of rational choice—implies that the social choice function must be the utilitarian rule—i.e., the weighting function must be equal to the utility functions of each individual. This result is known as Harsanyi's utilitarian theorem. According to Harsanyi's theorem, any non-utilitarian social choice function will be incoherent; in other words, it will agree to some bets that are unanimously opposed by every member of society. However, it is still possible to establish properties of such functions.
