There’s really three aspects of happiness that are widely used. One is life satisfaction. And then the second is positive emotion, feeling energetic or joyful. Now I know those sound like the same thing, but life satisfaction is thinking that your life is good. Overall you would say, “Oh, I wouldn’t want to trade my life with another’s.” Whereas this positive emotion thing is quite literally feeling positively. And those aren’t exactly the same thing. But the third aspect of happiness is actually very different, and that is the absence of negative emotion — the absence of anxiety and depression, worry and so forth. Those are three aspects. Economists tend to think about life satisfaction more.