The Gods are watching (Image: David, Jacques Louis (1748-1825)/Agnew's, London, UK/ The Bridgeman Art Library)

Many religions offers plenty of positive incentives to their followers – the promise of life after death, for instance. But why have religions that involve self-sacrifice and punishment survived? The link between support for a religion and a willingness to inflict punishment may point to the answer.

To study this link, Ernst Fehr at the University of Zurich in Switzerland and his team enrolled 304 people, mainly students. They were sorted into pairs and played 20 rounds of a game in which the first player was shown a monetary reward and had to choose one of two ways to split it with their partner: they could either share it equally or take a greater share for themselves.

The second player then had the option of punishing the first one by deducting from their reward. Dishing out punishment came at a cost, however: the punisher lost a reward unit for each three units they deducted from their partner.


Subliminal words

Fehr wanted to find out what motivated people to punish others. Before deciding on the punishment, the second player was subliminally shown a group of words. These either related to religion – like “divine”, “holy”, “pious” and “religious” – to secular punishment, or were neutral words like “tractor”.

After the game, all players were asked if they had donated money to a religious organisation in the previous year. The team found that those who had donated – about 15 per cent of participants – exacted the most severe punishments, but only after they had been shown the subliminal religious cues. When primed in this way, this group deducted roughly three times as many points on average as other players.

“We think that the cues give them a reminder they are being watched,” says psychologist Ryan McKay of Royal Holloway University of London, who co-led the study with Fehr. “To please the supernatural agent they worship, they exact higher punishments. The other possibility is that the cued words awakened the concepts of appropriate punishment in their minds.”

Painful rites

McKay points out that being religious can be costly in various ways: donating money, suffering painful rites and avoiding pleasures, for example. So the team wondered how religion survived, despite these apparent costs. “The answer may be that these sacrifices enable the group to secure more cooperation. The punishing may be unpleasant but it’s in the service of the greater good for that particular group or religion, enabling them to thrive and spread the word,” he says.

Chris Frith of University College London says previous studies have shown that people will impose punishments at a cost to themselves, and that this is a powerful means of maintaining group cooperation and reducing selfish behaviour. Fehr and McKay’s study suggests religion may enhance such behaviour, Frith says, and thus have a survival value.

But other motivations are possible too, Frith adds. “Appropriate secular ideas, such as socialism should, in principle, be equally effective in priming group-oriented behaviour.”

Journal reference: Proceedings of the Royal Society B, DOI: 10.1098/rspb.2010.2125