 This worry about the demands of utilitarianism is not easy to assess. One might wonder how to interpret and whether to accept the psychological realist constraint. If the constraint is relative to people’s actual psychologies, then it represents a potentially conservative constraint on moral theorizing that one might well reject. If the constraint is relative to possible or ideal psychology, then it is not clear that even a highly revisionary moral theory need flout the constraint. Then there is a question about how demanding or revisionary utilitarianism actually is. Mill and Sidgwick thought that our knowledge of others and our causal powers to do good were limited to those near and dear and other associates with whom we have regular contact, with the result that as individuals we do better overall by focusing our energies and actions on associates of one kind or another, rather than the world at large (U II 19; Sidgwick, Methods 361–69). On this view, utilitarianism can accommodate the sort of special obligations and personal concerns to which the critics of utilitarianism appeal. But it is arguable that even if this sort of utilitarian accommodation was tenable in nineteenth century Britain, technological development and globalization have rendered utilitarian demands more revisionary. Our information about others and our causal reach are not limited as they once were. Given the high benefit-to-cost ratio of many modern relief agencies, it is hard to resist something like Singer’s conclusions about the reformist demands of utilitarianism. So even if Mill was right to think that the motivational demands of utilitarianism were not so different from those of other moral theories at the time he wrote, that claim might need to be reassessed today.