  We consider social welfare functions when the preferences of individual
agents and society maximize subjective expected utility in the tradition of
Savage. A system of axioms is introduced whose unique solution is the social
welfare function that averages the agents' beliefs and sums up their utility
functions, normalized to have the same range. The first distinguishing axiom
requires positive association of society's preferences with the agents'
preferences for acts about which beliefs agree. The second is a weakening of
Arrow's independence of irrelevant alternatives that only applies to
non-redundant acts.
