WHAT INVESTIGATORS HAVE DISCOVERED
Although empirical research on happiness hardly existed be- fore 1970, it has since become a boom industry. Mounds of evidence have accumulated on how happy people claim to be in different countries, how their levels of contentment vary from one subgroup of the population to another, and what conditions or experiences are most closely related to the way people feel about their lives.' Several thousand articles have now been published on the subject. Books on how to be happy fill entire shelves in Borders and Barnes & Noble. International conferences abound. There is even a scholarly journal devoted ex- clusively to the topic.
Happiness is a large word encompassing many shadings of feel- ing and emotion. No single definition can do full justice to all that it embraces. The dean of American happiness scholars, Ed Diener of the University of Illinois, does his best to respond by offering the following comprehensive definition: “a person is said to have high [well-being or happiness] if she or he experiences life satisfaction and frequent joy, and only infrequently experiences unpleasant emotions such as sadness or anger. Contrariwise, a person is said to have low [well-being or happiness] if she or he is dissatisfied
Some authors who write on the subject speak of happiness, others of well-being or
subjective well-being, still others of satisfaction with life. These terms have slightly different
meanings. Happiness seems to refer to one's immediate feelings and impressions while satis-
faction connotes a more cognitive appraisal of one's life as a whole. However, investigators
find that groups of people respond quite similarly whether they are asked how happy or
how satisfied they feel about their lives.1 As a result, researchers tend to use the terms inter-
changeably. I do likewise throughout this book, while noting the occasional cases in which
the precise words used make a meaningful difference in people's responses.