Christians gather for prayers during a march organised by The Indian Christian Voice and The Catholic Secular Forum in Mumbai on Sunday. (AFP)

New Delhi, Oct. 5: Religion makes people helpful and honest, but mainly when it bolsters their reputation or when religious thoughts get freshly activated in their minds, new research suggests.

Two psychologists in Canada, who reviewed decades of research from anthropology, experimental economics and psychology, have said the association between religion and altruistic behaviour appears conditional.

“Experimentally induced religious thoughts reduce rates of cheating and increase altruistic behaviour among anonymous strangers,” researchers Ara Norenzayan and Azim Shariff said in a review published on Friday in the US journal Science.

And the association between religion and pro-social behaviour — actions that benefit others in a group at a personal cost — is “most evident” mainly when there is a need to maintain a favourable social reputation, they said. The implication could be that such acts are as much an investment as a sacrifice.

“We’re trying to understand the origins of religion from a scientific perspective,” Norenzayan, associate professor of psychology at the University of British Columbia, told The Telegraph.

“We’re setting aside philosophical and moral issues associated with religion or God, and trying to understand how religion influences human behaviour and human society.”

Research by Norenzayan and Shariff, however, indicates that non-believers, too, can be as generous and helpful as believers. The rise of non-religious social institutions such as courts and police, they believe, may have facilitated non-religious altruism.

One study by the two psychologists last year had shown that reminders of secular authority had as much effect on generous behaviour in an economic experiment as reminders of God.

The findings appear to contradict well-known claims in literature and philosophy linking altruistic behaviour solely to religious belief.

For instance, in The Brothers Karamazov by Russian novelist Fyodor Dostoevsky (1821-81), Ivan Karamazov famously declares: “If God doesn’t exist, everything is permitted.” Eighteenth-century French thinker Voltaire said that “if there were no God, it would be necessary to invent him” to encourage moral behaviour.

Norenzayan, however, said: “Some of the most co-operative modern societies are also the most secular. People have found other ways to be co-operative — without God.”

Western and northern Europe, the psychologists wrote, provide examples of large, co-operative societies that are not very religious but retain intra-group co-operation and trust.

Their analysis also highlights the role of religion in promoting co-operation and allowing the growth of large human societies.

In the past, some anthropologists had suggested that human group sizes beyond about 150 people were likely to spontaneously divide or break up. This was based on research on primates by University of Oxford anthropologist Robin Dunbar who had shown five years ago that brain size can be used to predict the size of viable social groups — the larger the brain size, the bigger the group.

“The number for humans has been disputed, but what is not in dispute is that humans live in very large co-operative groups, far larger than 150. So evolutionary scientists have to explain how humans can live in such large societies,” Norenzayan said.

“It’s puzzling. Religion appears to promote co-operation and growth of large human societies, yet it is also a cause of distrust, prejudice and violence,” he said. “Religion promotes co-operation between groups, but also draws boundaries.”

The two psychologists have urged more research into religion and its impact on human society. Science needs to investigate how individuals determine “who are the beneficiaries of religious pro-sociality and who are its victims”, they said in their paper.