This dissertation argues that the desire satisfaction theory, arguably the dominant theory of well-being at present, fails to explain why depression is bad for a person. People with clinical depression desire almost nothing, but the few desires they do have are almost all satisfied. So it appears the theory must say these people are relatively well-off. A number of possible responses on behalf of the theory are considered, and I argue that each response either fails outright, or requires modifications to (...) the desire satisfaction theory which make the theory unattractive for other reasons. Advisors: Joseph Mendola and John Brunero. (shrink)