Does justice require that we be ageist?

This paper restates some of the principal arguments against an automatic preference for the young as advocated by Kappel and Sandøe, arguments many of which have been extant for over a decade but which Kappel and Sandøe largely ignore. It then goes on to demonstrate that Kappel and Sandøe's "indifference test" fails to do the work required of it because it can be met by unacceptable conceptions of justice. The paper develops a number of new arguments against what I have called "ageist" preferences for the young or for those with long life expectancy. Finally I show that Kappel and Sandøe must believe that murdering older people is less morally wrong than murdering the young and that people relying on arguments such as theirs will have to accept the moral respectability of killing the innocent in order to maximise units of lifetime.