Atheists score higher on IQ tests than religious people according to some research. Does this mean that people accept religious beliefs because they are dimwitted? Not necessarily.
Atheists are probably more intelligent than religious people because they benefit from many social conditions that happen to be correlated with loss of religious belief. When one looks at this phenomenon from the point of view of comparisons between countries, it is not hard to figure out possible reasons that more intelligent countries have more atheists and that more intelligent states in the U.S. also have more nonbelievers. Here are some. Highly religious countries:
Given that each of these factors are recognized causes of low IQ scores, there is little mystery about why religious countries score lower on IQ tests. Of course, the same phenomena are relevant to comparisons within a country, although within-country differences in these factors are generally smaller. Even so, the wealthier individuals in a country experience life differently than the poorer ones, developing higher IQ scores and greater religious skepticism.
Recent research concluded that part of the reason that people in less religious U.S. states have higher IQs is that they are better educated. According to the authors: "Education enhances rational thinking and provides people with rational, non-mystical mechanisms for understanding the world. In short, education provides people with the opportunity to seek a rational alternative to religious dogma."
This argument is reasonable but it is seriously incomplete. There are a lot more atheists in Europe than in the U.S. and this is not because Europeans are smarter or better educated.
As to the more inflammatory explanations, I doubt that religion causes stupidity if only because some of the most brilliant people of history, such as Isaac Newton, were highly religious like most of their contemporaries.
Whether intelligence causes people to reject religious belief is more complex. It is certainly plausible that highly intelligent people would have a problem accepting some of the more improbable beliefs required by their church. Moreover, modern science offers explanations for phenomena that were previously explained exclusively in terms of religion and intelligent people may prefer the scientific account.
In short, discussing correlations between IQ and religiosity without a grasp of the relevant underlying factors is something of a parlor game. It recalls the long and tiresome debate about the correlation between IQ scores and skin color that got a lot of people very excited but proved a scientific dead end.
The really interesting question buried in all of this is why atheism is sparked uniquely by contemporary conditions in developed countries. I addressed this issue in an earlier post that hurtled around the Internet. The gist of it is that religion helps people confront the terror of uncertainty in their lives. In modern states people get more complacent so that there is less of a market for religion. The inevitable consequence of all this is that religion will decline as human prosperity improves.
David Lose: Has Atheism Become a Religion?
I am the fortunate beneficiary of most of those things: I was taken to Catholic church by my mother, but I was doing much more reading on my own, and the religion just didn't take root. I didn't get to go to university until my late 30s, but I've been an atheist for as long as I've been a "grown-up". I'm not going to be made to feel bad about the advantages I've had, or the luxury of time to read and think about these issues: the challenge is to extend the advantages of health and education to the rest of the world.
And of course this analysis doesn't delve into the reasons why, in this country, young people are increasingly rejecting religion. A phenomenon that one might think had to do with being better informed (or educated) about religion and its roots, as well as increased exposure to arguments against belief.
Lack of understanding is comparable to lack of intelligence.
IQ can best be thought of measuring whether people get access to good of bad education. Access to good education tends to results in higher IQ numbers. It also tends to result in lower religiosity. Again, this is not a measure of intellect or capability, but of exposure and access.
I don't think atheist are more intelligent. I think we are simple exposed to wider ranges of knowledge and have been lucky enough to have the freedom and tools to critically question assumptions about the world we live in.
The fact that exposure tends to lead one away from religion (at least the one of their parents) may be why many fundamentalist ideologies are also anti-science and education.
"IQ tests measure motivation - not just intelligence"