In his original speciication of the goods governed by the difference principle, Rawls made no reference to leisure. As R. A. Musgrave pointed out, however, this omission leads to problems of both horizontal and vertical equity (Musgrave 1974, 629–632). To illustrate the first: if a skilled laborer working twenty hours per week makes the same income as an unskilled laborer working sixty hours per week, the difference principle would seemingly not concern itself with their inequality in leisure. Yet, to illustrate the second, if two individuals have identical earning capacities but different incomes because one chooses to surf all day off Malibu while the other works, the difference principle would seemingly favor the surfer.

Both worries are overstated. The difference principle applies not to speciic individuals, but rather to groups (TJ 56). Although Rawls tended toward identifying the least advantaged as those individuals with less than half the median income and wealth (TJ 84; JF 59), he also suggested the possibility of identifying the least advantaged either by social position, such as unskilled laborers, or as those who are disadvantaged in family or class origins, natural endowments, and luck (TJ 83–84). This choice affects the likelihood of the Malibu surfer being among the least advantaged. Moreover, comparisons are to be made in terms of the lifetime expectations of representative individuals, not actual earnings (TJ 56). Finally, leisure considerations might already be effectively included, if, for example, differences in leisure lead to inequalities in the social bases of self-respect.