>Of course correlations are not causation, and the negative correlation that I expect between religiosity and happiness does not mean that atheism makes people happier, or religion unhappier. What it means—and this is supported by several sociological studies (see here for one)—is likely that people either turn to religion or maintain their religion when their social situation is so dire that they’re unhappy. When conditions are good, and there’s lots of social support, including help for sick people, old people, free medical care, and so on, then there’s no need to be religious, no need to supplicate a god for what your society can’t provide. When you’re well off, your country gradually loses religion, the thesis of Norris and Inglehart in the preceding link.

>In short, what makes people happy is not religion, but material well being and the assurance of material aid. That’s supported by the study’s finding that immigrants, including Muslims from the Middle East, quickly gain the happiness of their new country, while (I suspect), still keeping their religion, though perhaps in an attenuated form.

This does not contradict my point- if you live in rural Appalachia, there's a good chance you have a pretty hardscrabble life. Religion is adaptive in this circumstance, and you can become happier by becoming religious. The author of the article you linked also goes on to quote Marx, saying that abolishing religion is curing the masses of their opium addiction, and curing them of their delusions. I would argue that irreligious people are just as delusional, but with different failure modes. Apathy, nihilism, and lack of a sense of self dominate the irreligious; moral absolutism dominates the religious.