Many Americans doubt the morality of atheists. According to a 2007 Gallup poll, a majority of Americans say that they would not vote for an otherwise qualified atheist as president, meaning a nonbeliever would have a harder time getting elected than a Muslim, a homosexual, or a Jew.
Many would go further and agree with conservative commentator Laura Schlessinger that morality requires a belief in God - otherwise, all we have is our selfish desires.
In The Ten Commandments, she approvingly quotes Dostoyevsky: "Where there is no God, all is permitted." The opposing view, held by a small minority of secularists, such as Richard Dawkins, Daniel Dennett, Sam Harris and Christopher Hitchens, is that belief in God makes us worse. As Hitchens puts it, "Religion poisons everything."
Arguments about the merits of religions are often battled out with reference to history, by comparing the sins of theists and atheists. (I see your Crusades and raise you Stalin!) But a more promising approach is to look at empirical research that directly addresses the effects of religion on how people behave.
In a review published in Science, psychologists Ara Norenzayan and Azim Shariff discuss several experiments that lean pro-Schlessinger. In one of their own studies, they primed half the participants with a spirituality-themed word jumble (including the words divine and God) and gave the other half the same task with nonspiritual words. Then, they gave all the participants $10 each and told them that they could either keep it or share their cash reward with another (anonymous) subject.
Ultimately, the spiritual-jumble group parted with more than twice as much money as the control. Norenzayan and Shariff suggest that this lopsided outcome is the result of an evolutionary imperative to care about one's reputation. If you think about God, you believe someone is watching.
Since the United States is more religious than other Western countries, this research suggests that Fox talk-show host Sean Hannity was on to something when he asserted that the United States is "the greatest, best country God has ever given man on the face of the Earth."
It is at this point that the "We need God to be good" case falls apart.
In his new book, Society Without God, Phil Zuckerman looks at the Danes and the Swedes - probably the most godless people on Earth. They don't go to church or pray in the privacy of their own homes; they don't believe in God or heaven or hell.
But, by any reasonable standard, they're nice to one another. They have a famously expansive welfare and health care service. They have a strong commitment to social equality. And - even without belief in a God looming over them - they murder and rape one another significantly less frequently than Americans do.
Denmark and Sweden aren't exceptions. A 2005 study by Gregory Paul looking at 18 democracies found that the more atheist societies tended to have relatively low murder and suicide rates and relatively low incidence of abortion and teen pregnancy.
So, this is a puzzle. If you look within the United States, religion seems to make you a better person. Yet atheist societies do very well - better, in many ways, than devout ones.
The first step to solving this conundrum is to unpack the different components of religion. In my own work, I have argued that all humans, even young children, tacitly hold some supernatural beliefs, most notably the dualistic view that bodies and minds are distinct.
Other aspects of religion vary across cultures and across individuals within cultures. There are factual beliefs, such as the idea that there exists a single god that performs miracles, and moral beliefs, like the conviction that abortion is murder. There are religious practices, such as the sacrament or the lighting of Sabbath candles. And there is the community that a religion brings with it - the people who are part of your church, synagogue, or mosque.
The positive effect of religion in the real world, to my mind, is tied to this last, community component - rather than a belief in constant surveillance by a higher power. Humans are social beings, and we are happier, and better, when connected to others. This is the moral of sociologist Robert Putnam's work on American life. In Bowling Alone, he argues that voluntary association with other people is integral to a fulfilled and productive existence.
The Danes and the Swedes, despite being godless, have strong communities. In fact, Zuckerman points out that most Danes and Swedes identify themselves as Christian. They get married in church, have their babies baptized, give some of their income to the church, and feel attached to their religious community - they just don't believe in God. Zuckerman suggests that Scandinavian Christians are a lot like American Jews, who are also highly secularized in belief and practice and have strong communal feelings.
American atheists, by contrast, are often left out of community life. Studies cited by Arthur Brooks in Gross National Happiness, which find that the religious are happier and more generous than the secular, do not define religious and secular in terms of belief. They define it in terms of religious attendance. It is not hard to see how being left out of one of the dominant modes of American togetherness can have a corrosive effect on morality.
The sorry state of American atheists, then, may have nothing to do with their lack of religious belief. It may instead be the result of their outsider status within a highly religious country where many of their fellow citizens, including very vocal ones like Schlessinger, find them immoral and unpatriotic. Religion may not poison everything, but it deserves part of the blame for this one.
Paul Bloom is a professor of psychology at Yale University and author of Descartes' Baby: How the Science of Child Development Explains What Makes Us Human.