 Assessing the value of a public good in terms of preference satisfaction, actual or rational, involves another problem: the impossibility of interpersonal comparisons. Suppose there are two indivisible public goods A and B, Bob prefers A while Sally prefers B, and Bob and Sally’s combined wealth suffices to buy only either A or B. Under a preference-satisfaction account of welfare, there arguably is no normatively defensible way to compare Bob’s welfare when A is purchased to Sally’s welfare when B is purchased or to compare what Bob would gain by purchasing and what Sally would gain by purchasing B. Dan Hausman has argued that this problem constitutes a reason to abandon the preference-satisfaction account of welfare because any moral theory that assesses situations fully or in part in terms of welfare requires interpersonal comparisons (Hausman 1995).