  First, one might identify a serious objection to utilitarianism, say, and then show how considerations of personal identity (or at least of what matters in identity) dissolve the objection. This is  the approach Parfit takes in Reasons and Persons. The  objection he is concerned to refute is Rawls' famous  “separateness of persons” charge, the contention that  utilitarianism fails to take seriously the distinction between  persons, because it controversially jettisons interpersonal  distributive principles in exactly the way we uncontroversially  jettison them intrapersonally (Rawls 1971, 22–27). That is, in  extending the principle of rational choice to society-wide  decision-making (via use of the imagined impartial spectator),  utilitarianism treats the interests of all members of society as if  they were the interests of one person, and so conflates different  persons into one. What Parfit suggests is that, if the objection  depends on a hard-and-fast metaphysical distinction between persons  (i.e., on the non-identity of different persons), and if this  distinction depends on the further fact of identity – a  nonexistent fact if reductionism is true – then the distinction is nothing to take seriously in the first place. Utilitarians, in  other words, may be reductionists, justifiably ignoring the  “distinctness” between persons – and the  distributive principles such a distinction might support –  because the non-identity of persons is just a less deep fact (Parfit  1984, 329–345; see also Broome 1991 for a reductionist-based argument in support of utilitarianism's account of goodness).