a1 University of Edinburgh
The priority view has become very popular in moral philosophy, but there is a serious question about how it should be formalized. The most natural formalization leads to ex post prioritarianism, which results from adding expected utility theory to the main ideas of the priority view. But ex post prioritarianism entails a claim which is too implausible for it to be a serious competitor to utilitarianism. In fact, ex post prioritarianism was probably never a genuine alternative to utilitarianism in the first place. By contrast, ex ante prioritarianism is defensible. But its motivation is very different from the usual rationales offered for the priority view. Given the untenability of ex post prioritarianism, it is more natural for most friends of the priority view to revert to utilitarianism.
I am extremely grateful to John Broome, Wlodek Rabinowicz, Bertil Tungodden and an anonymous referee for exceptionally detailed comments. I have also benefited from comments by audiences at Oxford and Konstanz. Support for this project was provided by the Arts and Humanities Research Council, and also by the Alexander von Humboldt Foundation, the Federal Ministry of Education and Research and the Program for the Investment in the Future of the German Government through a Sofja Kovalevskaja Award in the form of a Visiting Fellowship at the Philosophy, Probability and Modeling Group at the University of Konstanz.