Getty Images Simply viewing an image of Rodin's sculpture "The Thinker" promotes religious disbelief.

Most of the world’s population believes in God, or gods, but alongside them there are also hundreds of millions of nonbelievers. What makes one a believer or not?

Religious faith is likely a complex phenomenon, shaped by multiple aspects of psychology and culture, say the authors of a new study. But the researchers, Ara Norenzayan and Will Gervais of the University of British Columbia in Canada, showed in a series of clever studies that at least one factor consistently appears to decrease the strength of people’s religious belief: analytic thinking.

“Religion is such a big force in the world,” says Norenzayan, an associate professor of psychology. “Hardly a day goes by without allegiances made to God, but we know very little about it. We are trying to fill this gap in our knowledge.”

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In one study, the researchers correlated participants’ performance on a test of analytic thinking with measures of their religious belief. The thinking task included three problems requiring participants to analytically override their initial intuition. For example, one question asked: “A bat and a ball cost $1.10 in total. The bat costs $1 more than the ball. How much does the ball cost?” The immediate, intuitive response is 10 cents. Those who take the time to figure out the right answer (5 cents) are judged to be more analytical, and these people tended to score lower on the measures of religious belief.

The team then conducted four other studies showing that when people are primed to think analytically, it weakens the strength of their religious belief. In one experiment, researchers asked participants to look at images of sculpture: either Rodin’s The Thinker, a well-known portrayal of deep thought, or another artwork of a discus thrower that was matched to The Thinker for color and posture. (In a previous trial, the researchers confirmed that simply viewing Rodin’s work improved people’s performance on a syllogistic reasoning task.) Those who viewed The Thinker were also significantly less likely than the control group to say they believed in God.

In other trials, researchers primed analytic thought in subtler ways — for instance, by asking people to make simple sentences out of words, which included either thinking-related words like ponder or rational or control words like hammer and brown. Another task asked people to rate their religious beliefs on a questionnaire presented in one of two fonts: a clear, easy-to-process font or an italicized type that made the text difficult to read (previous research has found that presenting information in hard-to-read type boosts people’s ability to reason). Across the board, participants who were primed for rational thought were less likely to express religious belief. What’s more, researchers had measured religious belief in many of the participants several weeks prior to the analytic thinking experiments and found no difference between the groups.

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The impact of the thinking tasks was significant, but relatively small. Reported Science Now:

“We’re not turning people into atheists,” says Gervais. Rather, when the questionnaire responses of all subjects in an experiment are taken together, they indicate a small shift away from religious belief.

There are surely many factors at play here, but the researchers say their results suggest that one’s style of thought may be a crucial contributor to religious belief. Intuitive thinkers are more likely to be religious; analytical types, less so. “One explanation for belief is that it is based on a number of intuitions we have about the world around us. People don’t necessarily come to belief because they reason into it. Intuition helps us,” says Norenzayan.

For instance, the commonly held belief that the mind and soul are distinct from the body stems from intuition. “It is not based in logic or reason. That’s not why people find this compelling,” says Norenzayan.

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That’s not to say that one way of thinking is more valuable than the other, only that the friction between intuitive and analytical thinking may help explain the origins of religious belief — or disbelief. “We know that in human psychology there are two systems of thinking. System one is intuitive; it is rapid and effortless. System two is analytical, and is more reasoned and thoughtful. Our study supports the idea that analytic thinking can push people away from intuitive thinking,” says Norenzayan.

The authors stress that their findings only scratch the surface of how religious belief develops. Faith is a complicated thing, influenced by culture and experience, Norenzayan says, such as those who find religion during situations of fear or morality. “We are not saying that analytical thinking turns people against religion. … There are lots of things going on,” says Norenzayan. “Our findings do not suggest one form of thinking is better than the other either. We don’t believe that. Both are important and both have costs and benefits.”

The study was published Thursday in the journal Science.

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