How many people should there be? Can there be overpopulation: too many people living? I shall present a puzzling argument about these questions, show how this argument can be strengthened, then sketch a possible reply.

1. Introduction. In a famous passage near the beginning of A Theory of Justice, John Rawls discusses utilitarianism’s notorious difficulties with justice. According to classic forms of utilitarianism, a certain course of action is morally right if it produces the greatest sum of satisfactions. And, as Rawls points out, the perplexing implication is “…that it does not matter, except indirectly, how this sum of satisfactions is distributed among individuals any more than it matters, except indirectly, how one man distributes his (...) satisfactions over time.” He concludes the passage by saying that “[u]tilitarianism does not take seriously the distinction between persons.”. (shrink)