 For helpful comments, many thanks are due to Anna Alexandrova, Robert Biswas-Diener, Thomas Carson, Irwin Goldstein, Richard Lucas, Jason Raibley, Eric Schwitzgebel, Stephen Schueller, Adam Shriver, Edward Zalta, and an anonymous referee for the SEP. Portions of Section 2 are adapted from Haybron 2008, “Philosophy and the Science of Subjective Well-Being,” in Eid and Larsen, The Science of Subjective Well-Being, and used with kind permission of Guilford Press.