Commentary Are people happy? It’s difficult to know even whether they think they are. Certainly, people are disgruntled lately. According to explosive new data from the General Social Survey, 24 percent of Americans say they’re not too happy, and only 19 percent say they are very happy. A lot of that disgruntlement is about COVID. But consider. The Harris Poll Survey of American Happiness reported that in 2017, low numbers of people called themselves “happy” (33 percent). But in 2020, the Gallup Poll reported that very high numbers said they were “satisfied with their personal life” (about 90 percent). People didn’t suddenly become happier during those three years; the Gallup percentage was almost as high in 2017 as in 2020. The difference was due to how the question was asked. As I explain in my new book “How and How Not to Be Happy,” it really is possible to study happiness—but …