Flourish: A Visionary New Understanding of Happiness and Well-being | 
It turns out, however, that how much life satisfaction people report is itself determined by how good we feel at the very moment we are asked the question. Averaged over many people, the mood you are in determines more than 70 percent of how much life satisfaction you report and how well you judge your life to be going at that moment determines less than 30 percent.
I used to think that the topic of positive psychology was happiness, that the gold standard for measuring happiness was life satisfaction, and that the goal of positive psychology was to increase life satisfaction. I now think that the topic of positive psychology is well-being, that the gold standard for measuring well-being is flourishing, and that the goal of positive psychology is to increase flourishing.
