Field of Science

Did world religions help bring about complex societies?

This is a long post, but hang on in there because it's worth it. There's a wonderful paper just out in Science that sheds new light on a mystery of human behaviour: why do people sometimes do good deeds even when they gain nothing from it.

Some forms of altruism can be easily explained by evolution, but evolution can't explain why people are sometimes generous to completely anonymous strangers. This new study may have found a solution: it isn't something inherent to our nature, but rather something that we learn to do.

You might have seen something of it already - it's featured on several news wires. I'm not going to go into detail on the headline results, because you can find them elsewhere (Wired magazine has a nice write up, for example).

What interests me most about this study is the link they found to religion. But first, here's a quick overview of what they did, and the major finding. The heart of the study was a standard battery of economic games designed to test their subject's understanding of fairness:
  • In the 'Dictator Game' Player 1 is given a fixed pool of money (equal to 1 day's wages), and can share as much (or as little) as she likes with Player 2.
  • In the 'Ultimatum Game', Player 2 is given the chance to reject offers that she feels are insultingly small.
  • In the 'Third Party Punishment Game' a third player is given some money as well, and she can spend some of it to punish Player 1, if she thinks that the offer to Player 2 is too small.
Now, the logical thing to do in all these games is to hold on to all your money. You have nothing to gain by sharing (the games are anonymous), and all that happens is that you go home with less. However, what usually happens is that people do share some money (usually not 50%, however!).

What makes this new study unique is that they've put together data from the world over, including the rather marvellous Hadza (you can see the locations on the map). Then they compared how much people contributed with what kind of society they lived in.

They found that contributions were smallest in societies that did not have a market economy (e.g. hunter gatherers). And they found that punishment was lowest in societies formed of small groups.

This potentially resolves the conundrum! What it suggests is that anonymous altruism is not part of our evolutionary make up, but instead is something that we learn from the society around us. The reason big, complex societies can exist is that we drum it into our kids that they must be fair and kind to strangers (against their natural instincts).

So what's the connection with religion?

Well, they also showed that, in two out of the three games, the anonymous contributions were higher in those groups that had converted from tribal religions (in which gods do not enforce morality) to follow a 'world religion' (in practice, either Christianity or Islam).

On the face of it, this is supports the idea that 'world religion' is a cultural adaptation to allow the formation of complex societies. The invention of and all-seeing, morally concerned god increases the honesty in anonymous transactions, and thus allowing large, integrated communities to develop.

When you look at the history of religions, it's clear that the development of religious ideas has progressed in tandem with the increasing complexity of society. Robert Wright has written a book on the topic, and in the supplementary material the study authors give a nice summary of these ideas.

It all sounds very plausible. However, it's not quite that simple, for a whole host of reasons.

First is the problem that a 'world religion' may be a consequence, not a cause, of a complex society. A world religion is essentially one that's popular over large geographic area. However, the exchange of ideas that always goes together with the exchange of goods will inevitably bring about a convergence of beliefs to create a 'world religion'.

So you would expect a complex, diverse society to develop some kind of syncretic belief system - a 'World Religion'. And that belief system would inevitably encapsulate the social norms of the complex society that created it. People create a god in their image.

Suppose, for example, that countries with more parasites end up with more fractured societies that are naturally less trusting of strangers. After all, strangers could bring with them disease. Surprisingly, studies have found that this is exactly the pattern you see - people living in high parasite regions are less open to strangers and have more fractured religions (Fincher & Thornhill, 2008). These societies, with their tribal rather than world religions, would naturally be less co-operative in anonymous games.

Perhaps moralising gods moralising gods are not required for complex societies. After all, the Romans and Greeks managed created large, complex societies despite having a pantheon of gods who were not exactly paragons of virtue.

And the reality is that, in modern societies at least, non-belief is correlated with less corruption and more trust. Social norms, rather than god beliefs, seem to be of primary importance.

As support for the hypothesis that 'world religions' promote pro-social behaviour, they quote the work of Shariff & Norenzayan. That was a small study which found that, in a similar economic game, subliminal religious primes (i.e. a quick flash of a religious word) were marginally more effective in believers than non-believers.

However, they also showed that non-religious primes were equally effective, and also that without the priming both religious and non-religious were equally pro-social. What's more, other studies (Randolph-Seng & Nielsen, 2007, Ahmed 2009) have shown that pro-social effects of religion are all about the situation, rather than the beliefs.

Put these findings together, and what you get is the strong suggestion that the way to encourage pro-social behaviour is to remind people about their cultural training (religious or otherwise). The more you reinforce a social norm of co-operation, the more people will co-operate.

Now, that doesn't rule out a role of religion in stabilising societies. In fact, I'm inclined to that that there must be a link. But it is fearsomely difficult to prove, and it's clear that whatever the link is, it's much more complicated than it appears at first sight.

I'm going to leave you with one other niggling anomaly from the paper. Remember that 'world religion' was associated with more pro-social behaviour in only two out of the three games? Maybe you were wondering which was the one out?

Well, the game that was the 'Third Party Punishment' game. This is the game in which Player 1 should give more money if they fear that Player 3 might spend some cash to punish offers that were too low. It's a particularly relevant test because third party intervention to enforce the rules is a crucial feature of complex society.

Unlike the other two games, being Christian or Muslim had no effect on Player 1's offers. What makes this doubly fascinating is that this is the only game in which wealth and income affected Player 1's decisions.

The authors suspect it might be that the introduction of a 'judge' reduces the intrinsic motivation. In other words, the offers players make depends on what they think the judge will approve of, rather than what they themselves think is fair.

However, I couldn't help but be reminded of another study that looked at punishment behaviour in a similar game. They examined a cross-section of relatively high income countries, and found high levels of co-operative punishment, and low-levels of anti-social punishment, in the least religious societies (Copenhagen and Melbourne).

Conceivably, if you don't believe that there is a god on hand to enforce the rules, you might just be motivated to do it yourself!

ResearchBlogging.orgHenrich, J., Ensminger, J., McElreath, R., Barr, A., Barrett, C., Bolyanatz, A., Cardenas, J., Gurven, M., Gwako, E., Henrich, N., Lesorogol, C., Marlowe, F., Tracer, D., & Ziker, J. (2010). Markets, Religion, Community Size, and the Evolution of Fairness and Punishment Science, 327 (5972), 1480-1484 DOI: 10.1126/science.1182238

Creative Commons License This article by Tom Rees was first published on Epiphenom. It is licensed under Creative Commons.


  1. "evolution can't explain why people are sometimes generous to completely anonymous strangers"

    Not true. You can be generous to anonymous strangers by accident and this could have a benefit. We see this everywhere in nature. A flower is generous to a bee. Generosity to anonymous strangers can also be a side effect of consciousness, feeling empathy.

    And even IF generosity to completely anonymous strangers only developed when religions were formed this would still be evolution.

  2. Some forms of altruism are readily explained in terms of natural selection - the flower/bee transaction, for example (which isn't anonymous). However, the form of altruism revealed in the economic games used in in this study has so far eluded any evolutionary explanation.

    The key conclusion from this study is that it can be explained in terms of cultural, rather than genetic, evolution. Competition between social groups favoured those that adopted the most effective forms of co-operation (i.e. cultural group selection).

  3. Altruism also makes you feel good, it feels nice to help someone.

  4. But why does it make you feel nice? After all, eating feels good because it's helping us achieve our evolutionarily-driven goals. Emotions are subject to natural selection too!

  5. [I write this comment before having read but the first paragraph of the post.]

    why do people sometimes do good deeds even when they gain nothing from it.

    That's like asking why people play the lottery when they didn't win. Obviously, because time-travel (backwards) isn't possible. You cannot know the future (until you get there).

  6. Who did the Hadza and other groups play with? Only other members of their group, or someone else, too?

    What the difference between co-operative punishment, and anti-social punishment?

  7. Lastly, as I've said before in comments to other posts, anonymity is an illusion. While humans may rationally believe it, emotionally we never get it.

  8. The more you reinforce a social norm of co-operation, the more people will co-operate.
    -- Tom

    I use to live in China where loud speakers would daily remind us of cooperating with the Communist dream. China was a disaster until free markets were introduced. The reinforce cooperation had instead turned their world full of ugly backbiting and much worse. I guess "HOW" one reinforces must be part of your solution to possibly succeed.

  9. This is consistent with my gut feeling, that organized religion had some utility in our distant past, and may have even been crucial in catalyzing highly complex societies (Guns, Germs, and Steel provides a very intriguing account of this, though granted it is somewhat of a "just so" story) -- but that the utility is long past. And in fact I think the utility ended before many people with similar views might estimate, e.g. I give no credit to the cults surrounding Moses or Jesus for advancing moral philosophy one iota.

    But it seems plausible -- and it is my gut feeling -- that religion "greased the wheels" in transitioning to a collective society, by giving people a (false) incentive to put the needs of the state above their own. In a happy accident, it turned out that, when properly organized and kept sufficiently in check, the state can legitimately provide benefits to the people, as opposed to just promising rewards in a mythical afterlife that never comes. Early states could do no such thing, and so relied on the lies of religion in order to flourish.

    Or that could all just be made-up speculation :) But that's the story I like.


    [I]f you don't believe that there is a god on hand to enforce the rules, you might just be motivated to do it yourself!

    Preach it, brother!!

    Altruism also makes you feel good, it feels nice to help someone.

    Heh, this comment reminds me of a semantic problem I often experience in conversations with other people.

    Me: How does Technology X work?

    Other person: Oh, it's simple! You just press this button, and then enter this information, and then out comes the widget.

    Me: No no, I see how you use it, I mean how does it work?

    Other person: (becoming increasingly exasperated) Well, see, after you press the button, then you enter the information. Then you get the widget. It's really very simple.

    Me: Okay, I got that, but how does -- agh, nevermind.

    This happens far too often :/

  10. Oh, and BTW, in regards to the first Anonymous comment, I have to partially agree, that I don't think it's completely implausible that the result of these games are explicable by a misfiring of impulses associated with kin selection. To put it as an analogy, stranger altruism is to family altruism as sex with birth control is to reproductive sex.

    Of course, this study contradicts that account, or at least demonstrates that it is not the whole story. It still seems likely to me that a misfiring of kin selection-caused impulses is involved, but that highly complex societies exploit and refine these instinctual impulses to generate something else altogether (analogous to the way in which the speech centers in our brain can be harnessed for written language and mathematics). It just seems implausible to me that any type of societal indoctrination, no matter how strong, could summon a new mode of behavior sui generis that manifests itself almost universally among the entire population. In order for the imperative towards anonymous altruism to have been so successful, it must be harnessing an instinctual impulse. Or so it seems to me.

  11. Bjørn, each group only played with other members of the same group. So it's a measure of in-group altruism.

    Re: the anonymity. They deal with it at some length in the supplementary material. I'm travelling and don't have it to hand, but they did make some strong arguments that it wasn't a relevant factor. If anything, you might expect westerners to be more comfortable with the idea of anonymity, given that we are used to dealing with anonymous situations.

    Anyway, the key point is that traditionalists are not altruisitc in this game. Therefore the mechanism for altruism (whatever it is) is learned, not innate.

  12. James, the interesting thing about religion is that it leverages kinship relations - all your co-religionists are your spiritual brother/sister/father/mother.

    So it way well work by hijacking the instinctive kinship altruism and 'fooling' the brain into acting towards non-kin in a similar way.

    Of course, that opens the door to clever parasites - since they are not really your kin, they will gain by exploiting your misconceptions...

  13. Control for IQ? Apparently not.

    "The more you reinforce a social norm of co-operation, the more people will co-operate."

    This has been tried throughout history with limited success.

    Smarter people cooperate more than less smart people. If smart people are atheist, then you can't necessarily claim they are trusting because they are godless, it might be because they have low time preference.

  14. "Of course, that opens the door to clever parasites - since they are not really your kin, they will gain by exploiting your misconceptions..."

    There are plenty of ways to con people. Simple betrayal after stringing their logical thinking along works a treat - if you give me $10,000 I'll invest it wisely and give you $15,000 very soon. Check out my portfolio of satisfied clients. Oops, I've run off with your $10,000. I don't think religion was needed, evolved to exploit people.

  15. I don't know of any evidence linking IQ to pro-social behaviour. It is clear, however, that people can assimilate social behaviour (pro or otherwise) from the culture in which they are raised.

  16. Tom, I disagree with much of your analysis on this issue. First, the discussion opens in the middle of a highly co-evolved system: Complex society (cities and states) formed beginning about 10,000 years ago, in the Neolithic, always with organized religion. ‘World’ religions appeared well into the common era and have been developing for ~1500 years when your modern snapshot is taken. Any suggestion that Christianity or Islam ‘caused’ complex society does not seem defensible. A corollary suggestion that organized religion caused complex society is, I think, very reasonable and strongly supported by 10,000 years of data. I would further suggest that world religion - any currently surviving modern state variety – or something very similar, is required to maintain a modern complex society at this time. This is a much more speculative claim, requires 50 to 100 years of testing, and subject to a social innovation rendering religion obsolete. My contention is that such an innovation has not yet been developed and that the current spat of atheism is temporary and has an environmental explanation.

  17. Well, the author's argument is that a religion that involves a god that enforces honest transactions is essential for the development of complex societies in which dealing with strangers are relatively frequent.

    I suspect that the opposite is the case. The large-scale societies developed social norms of trust, and that these social norms were incorporated into their religion (since we create religion as a mirror of our society).

  18. The data says that the first complex societies built temples and buried priests. My belief is that the primary function of both was, to borrow your word on it: ‘priming’ the population. Fill their minds with pomp and ceremony; build very visible monuments that are never far from their center of attention. One very necessary behavior change for these new ‘surplus economies’ was getting out to the fields every day to tend to crops or flocks. Hunting the animals or collecting the nuts that nature raised was much more time efficient than doing much of the work yourself, plus kings and priests do not produce but still had to be fed. My suspicion is that getting people to work on time was at least if not more important than ‘play nice’, but I’m not sure how to test for that. Our oldest ‘oral traditions’ Homer, Gilgamesh, Torah etc. reach back 3 to 4 millennia, not the 10 we need to ‘see’ the early days.

  19. This comment has been removed by the author.

  20. Thought up a few ‘tests’ driving home – all point to ‘keep the peace’ as the prime requirement for complex society. One obvious measure is the first function to warrant its own dedicated specialists. As the first urban professionals, priests were required to be generalists: Judges and written laws first appeared in the late Bronze, early Iron Age with domestic ‘police’ in Iron Age Greece and Rome. Publicly funded schooling, which does a fair job of teaching punctuality is quite recent – post industrial revolution. Suggesting that getting farmers to their fields was handled acceptably without dedicated specialists.


Markup Key:
- <b>bold</b> = bold
- <i>italic</i> = italic
- <a href="">FoS</a> = FoS