Cardinal Welfare, Individualistic Ethics, and Interpersonal Comparison of Utility: Comment

NOT very recently, Professor John Harsanyi (1955) presented in this Journal three appealing axioms for social choice under uncertainty which lead to the conclusion of a social welfare function which is additive in individual utilities. While not directly addressing his defense of these axioms, I wish to argue that one of them is not consistent with notions of justice held by some individuals.' Since this is an ethical discussion, the argument will take the form of an example which suggests the problem inherent in the axiom and some comments on the nature of the example. Harsanyi's three axioms are: (1) individual decision making satisfies the axioms for expected utility maximization; (2) social welfare can be written as an increasing function of individual expected utilities; and (3) social choice satisfies the axioms for expected utility maximization. It is the third axiom with which I wish to quarrel. In mathematical terms, we can express the first axiom as individual choice conforms to the maximization of expected utility, vi, where