The Frontal Cortex

Religion and Tribal Cooperation

A commenter asked an astute question in response to my post on religion and dietary laws:

What are your thoughts on kashrut primarily as a means of group indentity reinforcement, ritual, and control? In pre-literate times or in unstable social settings, wouldn’t dietary habits be a useful means of tracking who is and is not a member of one’s tribe? (Dietary laws also have the effect of confering monopoly power to those preparing and selling the food.)

I think the function of these religious laws – and the Old Testament is stuffed full of such laws – goes well beyond mere identification. While it’s nice to know who is a member of the tribe, these dictates from above also help grease social interactions within the tribe. Via Razib, the Economist recently had an interesting article on the phenomenon:

To test whether religion might have emerged as a way of improving group co-operation while reducing the need to keep an eye out for free-riders, Dr Sosis drew on a catalogue of 19th-century American communes published in 1988 by Yaacov Oved of Tel Aviv University. Dr Sosis picked 200 of these for his analysis; 88 were religious and 112 were secular. Dr Oved’s data include the span of each commune’s existence and Dr Sosis found that communes whose ideology was secular were up to four times as likely as religious ones to dissolve in any given year.

A follow-up study that Dr Sosis conducted in collaboration with Eric Bressler of McMaster University in Canada focused on 83 of these communes (30 religious, 53 secular) to see if the amount of time they survived correlated with the strictures and expectations they imposed on the behaviour of their members. The two researchers examined things like food consumption, attitudes to material possessions, rules about communication, rituals and taboos, and rules about marriage and sexual relationships.

As they expected, they found that the more constraints a religious commune placed on its members, the longer it lasted (one is still going, at the grand old age of 149). But the same did not hold true of secular communes, where the oldest was 40. Dr Sosis therefore concludes that ritual constraints are not by themselves enough to sustain co-operation in a community-what is needed in addition is a belief that those constraints are sanctified.

Dr Sosis has also studied modern secular and religious kibbutzim in Israel. Because a kibbutz, by its nature, depends on group co-operation, the principal difference between the two is the use of religious ritual. Within religious communities, men are expected to pray three times daily in groups of at least ten, while women are not. It should, therefore, be possible to observe whether group rituals do improve co-operation, based on the behaviour of men and women.

To do so, Dr Sosis teamed up with Bradley Ruffle, an economist at Ben-Gurion University, in Israel. They devised a game to be played by two members of a kibbutz. This was a variant of what is known to economists as the common-pool-resource dilemma, which involves two people trying to divide a pot of money without knowing how much the other is asking for. In the version of the game devised by Dr Sosis and Dr Ruffle, each participant was told that there was an envelope with 100 shekels in it (between 1/6th and 1/8th of normal monthly income). Both players could request money from the envelope, but if the sum of their requests exceeded its contents, neither got any cash. If, however, their request equalled, or was less than, the 100 shekels, not only did they keep the money, but the amount left was increased by 50% and split between them.

Dr Sosis and Dr Ruffle picked the common-pool-resource dilemma because the communal lives of kibbutz members mean they often face similar dilemmas over things such as communal food, power and cars. The researchers’ hypothesis was that in religious kibbutzim men would be better collaborators (and thus would take less) than women, while in secular kibbutzim men and women would take about the same. And that was exactly what happened.

Of course, the social benefits of religion come with a high price-tag. God-based tribalisms might foster intra-group cooperation, but they also encourage inter-group frictions.


  1. #1 yogi-one
    March 27, 2008

    A lot could done with these types of studies.
    It would be interesting to see who is more likely to start a war with neighboring communities – secular or religious?
    Which type of commune will have more vicious punishments for members who violate the codes of the commune?
    Which type of commune embraces technological or social innovation more easily?
    Which type of commune is more authoritarian or more egalitarian? Why?

  2. #2 HP
    March 27, 2008

    There’s a more prosaic explanation for kashrut (and halal) that’s historical rather than sociological: At the time most dietary restrictions were formulated, sacrificial cults were the primary mode of expressing religious community and the primary means of distributing protein among a population.

    As it turns out, foods like pork or “kid seethed in goat’s milk” are sacrificial meals linked to competing religious cults (IIRC, suckling pigs with Demeter, and kid/goat’s milk with Astarte). So, it’s partly magical thinking (“If I eat pork, that means I’m worshiping Demeter! And I don’t even know it!”) and partly with ensuring that competing religious cults don’t gain a toehold in the community (Persian: “Care for some seethed kid? It’s delicious!” Jew: “No, thanks. I worship the Lord!”).

    These kinds of considerations would be particularly important to a monotheistic community surrounded by pagans. For a polytheist to eat meat associated with some cult other than his family or city deity is just good manners. Interestingly, the biggest threat to social order in pagan society was vegetarianism. Christianity got in well in ancient Greece, because Christians would eat whatever meat was offered. But groups like Orphists and Pythagoreans were roundly condemned, because they were vegetarian, which was tantamount to rejecting the whole social structure of pagan religion.

    I think the connection between dietary restrictions and sacrificial practice would’ve been blindingly obvious to a Late Bronze Age audience, but with the Cult of the Sacrifice some 1500 years in the past, we tend to look for more esoteric explanations.