I’ve discussed this paper with just about everyone I know. Thanks to Elizabeth Anderson, Rachael Briggs, Lara Buchak, Sarah Buss, Justin D’Arms, Tom Dougherty, Dmitri Gallow, Alex Guerrero, Elizabeth Harman, Scott Hershovitz, Ishani Maitra, Julia Markovits, Jill North, Timothy Schroeder, Andrew Sepielli, Ted Sider, Rohan Sud, Sigrn Svavarsdóttir and Julie Tannenbaum for suggestions that particularly improved the paper. This paper was presented to the EDGe group at the University of Michigan and the philosophy department at Ohio State University, and I got valuable feedback at both of those presentations. The paper also served as my inaugural lecture as the Marshall M. Weinberg Professor at the University of Michigan. Marshall has been a wonderful supporter of the University of Michigan for many years, and especially of its philosophy department, and this was a tremendous honour. And the paper was presented at the 2013 Bellingham Summer Philosophy Conference. This is close to the Platonic Ideal of a philosophy conference. I’m incredibly grateful to Ned Markosian, and to all of the people who work with him to make this conference happen every year. And I’m very happy to have been able to present this paper at the 2013 conference. So to Marshall and to Ned, thanks.