Researchers at the University of Pennsylvania found that views on sexual conduct reveal more about a person’s religious beliefs than their ideas about lying or cheating. This may not come as too big of a shock considering we recently learned that, when it comes to financial gain, people with stronger religious affiliations may be more willing to deceive than others.

But it does mean that religion may have less to do with morality and more to do with sex. The more conservative a person’s views on casual sex, abortion and contraceptives are, the easier it is to predict how strongly they hold to their religious beliefs, according to research by Jason Weeden and Robert Kurzban. Tracy Clark-Flory reports at Salon:

This study raises the possibility that religion’s rise is more accurately attributed to its support of certain reproductive strategies. For those pursuing “committed partnerships, higher fertility, and cooperative parenting, both sexes’ interests are threatened by promiscuous sexual activity — for men, arising primarily from the risk of cuckoldry and, for women, arising primarily from the risk of mate abandonment.” (Is it just me or is evolutionary psychology super-depressing?) Thus, beliefs that reduce these threats also “advance the reproductive interests of” commitment- and baby-minded folks. On the other hand, those “pursuing a more promiscuous reproductive strategy” benefit when sleeping around carries little stigma or social costs. The report puts it this way:

If you live a lifestyle where a stable marriage and lots of children is important to you, belonging to a church mitigates some of the risks that go along with that lifestyle, making religion an attractive tool. But if you’re, say, a college student who likes to party and isn’t planning to get married or have kids for a long time, all you’re getting from a religion is a bunch of hassles.

This study doesn’t definitively prove a causal relationship, let alone a causal direction. But Weeden tells me that, based on his research and analysis, the more plausible explanation is that reproductive strategies influence religious beliefs, rather than that religious beliefs influence reproductive strategies. “This doesn’t settle the matter once and for all, but it’s a strong sign that at least some of the causality goes from lifestyles to religion,” he says.

Clark-Flory acknowledges that these speculations are “highly heretical,” and it could be offensive to both believers and nonbelievers to suggest sex is the root of religious motivation rather than spiritual or intellectual convictions. And yet, she points out, “it certainly isn’t the first time our motivations have been boiled down to sex.”

—Posted by Natasha Hakimi

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