 The first claim, that most people are happy, appears to be a consensus position among subjective well-being researchers (for a seminal argument, see Diener and Diener 1996). The contention reflects three lines of evidence: most people, in most places, report being happy; most people report being satisfied with their lives; and most people experience more positive affect than negative. On any of the major theories of happiness, then, the evidence seems to show that most people are, indeed, happy. Yet this conclusion might be resisted, on a couple of grounds. First, life satisfaction theorists might question whether self-reports of life satisfaction suffice to establish that people are in fact satisfied with their lives. Perhaps self-reports can be mistaken, say if the individual believes herself satisfied yet shows many signs of dissatisfaction in her behavior, for instance complaining about or striving to change important things in her life. Second, defenders of affect-based theories—hedonistic and emotional state views—might reject the notion that a bare majority of positive affect suffices for happiness. While the traditional view among hedonists has indeed been that happiness requires no more than a &gt;1:1 ratio of positive to negative affect, this contention has received little defense and has been disputed in the recent literature. Some investigators have claimed that “flourishing” requires greater than a 3:1 ratio of positive to negative affect, as this ratio might represent a threshold for broadly favorable psychological functioning (e.g., Larsen and Prizmic 2008). While the evidence for any specific ratio is highly controversial, if anything like this proportion were adopted as the threshold for happiness, on a hedonistic or emotional state theory, then some of the evidence taken to show that people are happy could in fact show the opposite. In any event, the empirical claim relies heavily on nontrivial philosophical views about the nature of happiness, illustrating one way in which philosophical work on happiness can inform scientific research.