Religion vs. IQ - Are Religious People Stupid?
by Rich Deem


Correlation Between Faith and Intelligence?

Atheists have noted a negative correlation between the practice of religion and the intelligence quotient (IQ). Does this mean that religious people are stupid? Are atheists more intelligent?

Rich Deem

It is commonly assumed that religious people are less intelligent than those who who aren't religious. Many skeptics think that Christianity and other religions are for people who do not want to think - but will blindly follow what they are told by their church. While it is true that those who have advanced degrees tend to be more atheistic than those who don't, does this correlate with intelligence or just self-sufficiency? Let's look at the data that is purported to show a negative correlation between IQ and religiosity.

Importance of religion vs. IQ

Religious importance vs IQA few years ago, some bored researchers decided to plot the importance of religion in people's lives vs. IQ from several countries throughout the world.1 The results are quite impressive (See figure to right), with a correlation coefficient of nearly 0.9 (1.0 is perfect). So, this proves that dumb people are attracted to religions, right?

What about GDP vs. IQ?

GDP per capita vs. IQHowever, if you look at the raw data, some of the countries are quite wealthy, while others are quite poor. Obviously, in those countries that are poor, there is little chance for higher education, and IQ scores are bound to suffer as a result. So, I looked up the gross domestic product per capita (GDP) on the CIA's World Factbook website,2 and plotted those values compared to IQ. These results are likewise quite impressive (r = 0.7). So, the results show that people from poor countries don't score well on IQ tests. So, the question is whether being stupid causes people to be religious or whether just being poor causes people to be religious? Maybe even other factors might influence the prevalence of religion in different countries throughout the world.

Conclusion Top of page

Religion vs. IQ vs. GDPThe animated figure to the right shows the correlation of religion vs. IQ along side the correlation of GDP per capita vs. IQ.3 Since the slopes of the two curves are virtually identical, one would be hard pressed to claim that one factor or another was actually responsible for the prevalence of religion around the world. By the way, there is an outlier country in all this - the United States. People from the U.S. rate religion as being very important, although they have one of the highest IQ's. However, they also have the highest GDP per capita, which seems to be a more significant factor influencing IQ than religious involvement. In general, one could speculate that those who have a full belly would be less likely to consider their need for God. Why does the United States buck that trend, even though it was founded with a secular form of government? That's another story...

La Religión vs. C.I - ¿Son Estúpidas las Personas Religiosas?

References Top of page

  1. IQ Religiosity Redux and Religion vs IQ and IQ vs. Religiosity
  2. CIA - The World Factbook -- Field Listing - GDP - per capita (PPP) - last updated 2006.
  3. The original data can be found here (Excel File - Religion vs. IQ vs GDP 27 kb MS Excel file).
Last Modified March 20, 2007


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