What happiness science can learn from John Stuart Mill
Many researchers studying subjective wellbeing (SWB) understand SWB as a concept that is close to Bentham's notion of happiness. This conception of happiness is philosophically controversial, because it treats pleasure as a homogenous experience. I analyze an important deviation from Bentham in John Stuart Mill's Utilitarianism and its relevance for SWB research: qualitative differences in pleasurable experiences. I argue that in cases where lives involving qualitatively different experiences are compared, Mill's qualitative perspective is incompatible with an important assumption in the SWB literature: that happiness can be meaningfully rated by people on a scale. I illustrate the problem by means of the question of whether becoming a parent makes people happier. I analyze whether the problem can be avoided on alternative views of happiness, but argue that on all plausible accounts of happiness, the problem persists. I conclude that the problem it poses for self reported happiness is genuine and should be acknowledged by SWB researchers. I end by discussing the ways in which this conclusion can help the study of happiness move forward.