From the article:

“The evidence that there is a negative relation between intelligence and religiosity is very strong. But the effect size of the relation is small. This means that there are factors besides intelligence that explain why people are or are not religious. It also means that although more intelligent people tend to be less religious on the average, predicting religiosity from intelligence for individuals is fallible,” Zuckerman told PsyPost.”

That of course probably means measuring intelligence mainly in terms of IQ, scores. But real working intelligence, of the sort which matters in the complex human world, depends much more upon many qualities of character, besides just paper problem solving ability. Such as honesty, setting high standards, being prepared to put effort in, being willing to change even when it hurts, and patience, I would like to bet that if you could find a way to measure those too, the results would be even stronger.

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