Are More Intelligent People More Likely to be Atheists?

In this post, I criticized psychologist Satoshi Kanazawa’s widely discussed recent article claiming that more intelligent people are more likely to be politically liberal. Kanazawa also claims that his data shows that more intelligent people are more likely to be atheists. This claim is better supported than the article’s argument about political liberalism. Nonetheless, the evidence isn’t nearly as strong as Kanazawa suggests. My own conjecture is that Kanazawa may be right about countries such as the United States, where atheists are a small minority, but less likely to be correct about the many nations where atheists are a much larger fraction of the population.

On the plus side, Kanazawa’s measure of atheism (survey responses stating a lack of religiousity and lack of belief in God) is better than his extremely dubious definition of liberalism. Even this part of his analysis is not completely airtight, since lack of religiosity doesn’t necessarily equate to lack of belief in God. Still, the two are at least highly correlated, and Kanazawa gets similar results for a General Social Survey question that directly asks respondents whether they believe in God. Controlling for various other variables, including education, gender, and race, more intelligent respondents are more likely to say that they don’t.

Unfortunately, however, Kanazawa improperly generalizes from the US results. Only about 2 to 10 percent of Americans are atheists and agnostics. In an overwhelmingly religious society, it is probable that relatively more intelligent people would be more likely to question conventional wisdom – especially since many of the arguments for atheism are counterintuitive. Kanazawa wrongly assumes that atheism is just as uncommon in the rest of the world as in this country. He cites the fact that The Encyclopedia of World Cultures refers to atheism in its descriptions of only 19 cultures, all of them formerly communist societies where the government coercively imposed atheism on the population. Regardless of what that Encyclopedia might say, however, many nations that have never been communist have large numbers of atheists and agnostics (the distinction between the two is not relevant to Kanazawa’s analysis). According to sociologist Phil Zuckerman’s comprehensive article in the Cambridge University Press’ Cambridge Companion to Atheism, there are at least 500 to 750 million atheists and agnostics worldwide. To put it another way, atheism and agnosticism have more adherents than any religious group aside from Roman Catholicism and Sunni Islam. Survey data compiled by Zuckerman also shows that many never-communist countries have 30% or more of their population who fall into one of these two groups. These nations include Japan (65%), Norway (up to 72%), Denmark (up to 80%), Sweden, South Korea, Belgium, the Netherlands, Great Britain, and others. These figures are far from definitive. But they do suggest that atheism is a lot more common than Kanazawa assumes. In the absence of comparative data covering countries where atheism is widespread, Kanazawa’s US data don’t prove that there is any universal tendency for more intelligent people to become atheists.

The fact that atheism is so common in much of the world also undercuts Kanazawa’s and others’ claims that it runs counter to evolutionary instincts. Any such instinctive theism is likely to be relatively weak if atheism can become so widespread despite centuries of repression by political and religious authorities that ruthlessly suppressed it in most of the world up until at least the nineteenth century, or even later.