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Most cultures have a religion. However, most of those religions don’t actually involve a belief in a God (or Gods).

But then farming arose and populations began to grow bigger. In these large populations, belief in a law-giving “King” God became much more common. Since you’re likely living in a large population as you read it, these are the sorts of deities your probably most familiar with.

What  was it that prompted their appearance? Why did larger populations begin to believe in a moral-giving God?

All (in)equal in the eyes of God

A few years ago researchers identified a very interesting trend in the religious beliefs of different groups. Social size and group complexity was strongly correlated with a belief in a “King” God.

Only ~5% of societies with less than 1,000 people in believed in a law-giving God. A further 20% or so believed in an inactive God. But by far the majority didn’t even have a concept of a “deity”. Meanwhile more than 40% of groups with >10,000 members believed in such a deity; with an additional 40% also believing in an inactive God.

This same trend was seen with social complexity. Groups with no social stratification were much less likely to have an active deity (or even a deity at all) than groups with wealth distinctions and social classes.

Based on all this many researchers concluded that there was something about larger, more complex groups that necessitated a law-giving deity. One key hypothesis was that such a belief helps foster co-operation and avoid free-riders. Doing so becomes more and more important as a society becomes more and more complex.

The number of societies with a belief in a high-God, broken down by population size

The number of societies with a belief in a high-God, broken down by population size

More resources need to be produced to sustain it; which requires people working together. But that surplus of resources makes it possible for people to take from the pool without giving back. What better way to encourage people to do the former and avoid the latter than the commandments of a deity?

Additionally, inequality might also be necessary for these societies. They need a ruling class to govern. Nowadays they get their power from the “will of the people”, but might the “divine right of kings” be how they first got their authority? Certainly many religious texts preach loyalty to leadership.

Proof its not WEIRD

This hypothesis seems to make sense. However, it is ultimately just a lot of speculation based on general trends seen in society.

So researchers set out to see if belief in a law-giving God actually does encourage co-operation. Multiple studies seem to have proven that this is the case. “Priming” individuals with religious beliefs encourages them to be more generous and work with others in psychological games. In some studies, it almost doubled the amount of money individuals were willing to donate to an anonymous person.

The amount of money offered to a stranger after being primed by different concepts

The amount of money offered to a stranger after being primed by different concepts

However, most of this research is WEIRD. That is, conducted on Western, Educated, Industrialised, Rich, Democracies. These sorts of societies are an anomaly in human history, so there’s debate over whether or not these results can be applied to non-WEIRD societies. 

So researchers went out to test just how widespread these trends were. They examined thousands of individuals from dozens of societies spread across every continent (except that one inhabited only by penguins). And sure enough, they confirmed that the results seen in WEIRD societies were actually seen around the world. A belief in a law-giving God was correlated with increased levels of empathy, altruism, compliance, and honesty.

All of the key traits needed to foster co-operation.

Of course correlation is not the same as causation. It could work the other way around, with religion attracting people naturally more co-operative. However, the fact that these trends were so widespread amongst so many different cultures and religions makes this unlikely, in my opinion (although further research to confirm this is always welcome). Breaking down the data further to examine if it was religions with a “law-giving” God could certainly help with this.

Weird outcomes of religion

As well as showing that there was a correlation between religiosity and religion, these researchers also found religion was linked with a few other personality traits.

In particular, higher levels of religiosity were correlated with lower levels of sexual permissiveness. One of the big ways this manifested was less interest in short term mating; with religious people wanting to “settle down”. This trend was much more apparent in women than men; except for in people who had never had sex. Religious virgins of both genders were equally less interested in short term mating.

Curiously, this reduced sexual permissiveness was also seen in groups engaging in seemingly “unpermissable” sexual activities. Religious homosexuals and bisexuals also scored low on the scale, similar to their heterosexual counterparts. However, there was less difference between the genders.

Additionally, a negative correlation between religion and openness to new experiences was also found. However, it wasn’t as widespread as the other characteristics, being almost absent from Asian populations. In the West though, religion definitely made you less open to new experiences. And slightly less neurotic.

Are these characteristics an evolved part of religion? Do they enable the fostering co-operation? Is it coincidence? The prevalence of these attitudes suggests the latter is untrue, but beyond that there’s no clue about why these aspect of religious belief developed.


Belief in a law-giving god is hypothesised to foster co-operation. Cross cultural data confirms this is the case. Also, it shows religious people rank lower on the scale of sexual permissiveness.


Peoples HC, & Marlowe FW (2012). Subsistence and the Evolution of Religion. Human nature (Hawthorne, N.Y.) PMID: 22837060

Schmitt, D.P. and Fuller, R.C., 2015. On the varieties of sexual experience: Cross-cultural links between religiosity and human mating strategies.Psychology of Religion and Spirituality, 7(4), p.314.

Shariff AF, & Norenzayan A (2007). God is watching you: priming God concepts increases prosocial behavior in an anonymous economic game. Psychological science, 18 (9), 803-9 PMID: 17760777

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Wyrd Smythe · 14th January 2016 at 6:15 pm

Atheists often point to how religious people don’t always follow their own code… My reply has been to ponder how people would behave in the *absence* of any moral code. I’ve long believed that, whether based on reality or not, religion definitely has some social value.

    Adam Benton · 14th January 2016 at 6:31 pm

    Well the donation study kind of measures that. It turns out with no rule priming people were about half as generous.

      Wyrd Smythe · 15th January 2016 at 3:30 pm

      Yep, exactly. Just as a persistent social meme, religion seems to have social value. One problem is that the meme is mired in ancient perceptions. Perhaps, as we did with medicine, the trick isn’t turning our backs on it, but *updating* it to make it consistent with modern understandings of science.

        Adam Benton · 15th January 2016 at 10:49 pm

        It’s certainly interesting that secular primes – like “justice” and “law” – can have a similar effect. Are they the “updates” to the religious software; or are they appealing to another part of our brain. Its an interesting question.

        Wyrd Smythe · 16th January 2016 at 5:40 pm

        Very interesting, indeed. As your post says, “King” gods didn’t show up until society most needed them, which is suggestive.

        As society evolved and spiritual views clashed with scientific ones, we did get “updates” like Spinoza’s God of physical law, and there are flavors of religion where God is more absent than present and active daily.

        So who knows. For me, Occam’s Razor cuts such that I find it hard to believe all this stuff — the whole universe — “just happened” but beyond that I don’t have a clue. (I have enjoyed the recent speculations that we all live in a virtual reality. The idea explains so much, and it’s surprisingly hard to refute! 🙂 )

Neanderthalphile · 14th January 2016 at 10:25 pm

Hey Adam, I’m sure at some point you realized, just like me, that the evolved nature of religion is independent from the factual existence of any kind of deity.

Of course I will be charged with a cognitive bias, but in my life I’ve experienced such absurdly improbable coincidences, mathematically speaking, in exactly the very moments they had to show up (when they were most needed) that well, it makes you think in you know what.

Nothing special, nothing very interesting here. Just this strange feeling of a structure imposed on my life, which of course would be just an artifact of the structured nature of reality. But still…

How is it possible to reconcile this not only with my evolutionary mindset, but also with those tons of facts and arguments contrarian to the existence of something else?

I got no answers. For now, I don’t try to reconcile anything because I simply cannot. This is just a personal confession, so to speak.

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