The study also gets high marks from University of California, Irvine, evolutionary biologist Francisco Ayala, the only former president of the American Association for the Advancement of Science to have once been ordained as a Catholic priest, and who continues to assert that science and religion are compatible. Ayala calls the studies ingenious, and is surprised only that the effects are not even stronger. "You would expect that the people who challenge the general assumptions of their culture—in this case, their culture's religious beliefs—are obviously the people who are more analytical," he says.
The researchers, for their part, point out that both reason and intuition have their place. "Our intuitions can be phenomenally useful," Gervais says, "and analytic thinking isn't some oracle of the truth."
Greene concurs, while also raising a provocative question implicit in the findings: "Obviously, there are millions of very smart and generally rational people who believe in God," he says. "Obviously, this study doesn't prove the nonexistence of God. But it poses a challenge to believers: If God exists, and if believing in God is perfectly rational, then why does increasing rational thinking tend to decrease belief in God?"