Professor Arthur C. Brooks explores the happiness of religious versus nonreligious people. An excerpt:
How do religious Americans compare to the secular when it comes to happiness? In 2004, the General Social Survey asked a sample of Americans, "Would you say that you are very happy, pretty happy, or not too happy?" Religious people were more than twice as likely as the secular to say they were "very happy" (43% to 21%). Meanwhile, secular people were nearly three times as likely as the religious to say they were not too happy (21% to 8%). In the same survey, religious people were more than a third more likely than the secular to say they were optimistic about the future (34% to 24%).
The happiness gap between religious and secular people is not because of money or other personal characteristics. Imagine two people who are identical in every important way--income, education, age, sex, family status, race and political views. The only difference is that the first person is religious; the second is secular. The religious person will still be 21 percentage points more likely than the secular person to say that he or she is very happy.