Lost Wallet
© Snap Decision / Getty ImageFrustrating, but research suggests lost wallets often aren’t a lost cause.
An international experiment involving over 17,000 lost wallets has revealed that humans are far more honest and altruistic than anyone, including professional economists, had ever imagined.

The research, published in the journal Science, shows that our sense of self and the desire to help others are sometimes more powerful than self-interest.

The Scottish philosopher Adam Smith placed self-interest at the heart of human behaviour in his 1776 work The Wealth of Nations.

Classical economics still holds that rational self-interest is the key to economic activity and will, as a by-product, generate social benefits; but such assumptions don't always lead to accurate predictions about human behaviour.

Alain Cohn and Christian Lukas Zünd of the University of Michigan, in the US, Michel André Maréchal of the University of Zurich, in Switzerland, and David Tannenbaum, of the University of Utah, Salt Lake City, in the US have carried out a series of studies that show self-interest is only part of the picture.

The team set out to see if "people act more dishonestly when they have a greater economic incentive to do so". This is the prediction from classic economic models based on rational self-interest, which "suggest that, all else equal, honest behaviour will become less common as the material incentives for dishonesty increase".

Our understanding of honesty, up until now, has largely come from laboratory work, but exactly how these results translate to real world activity has been far from clear.

The key question is "whether such settings predict honesty outside the lab, where dishonesty often harms others, suggests Shaul Sharvi, of the University of Amsterdam, Netherlands, in a companion perspective in the same journal.

Cohn and team set out to test how honest people actually are in real life, something they call "civic honesty". To do so, they went to 355 cities across 40 countries and handed in 17,303 "lost" wallets to banks, theatres, museums, post offices, hotels and various public offices, including those of branches of law enforcement.

Each wallet was transparent and contained a collection of variables: a key; a grocery list and three identical business cards with the owner's identity and email address; and either US$13.45 in local currency or no money at all. These wallets were dropped off by research assistants claiming to be in a hurry who left no contact details.

The test then was to see at what rate people tried to contact the owners to return the wallet. Classic economic theory says that the wallets containing money should be returned at a lower rate than those without.

Cohn and colleagues found that the exact opposite was true. In 38 of the 40 countries, "citizens were overwhelmingly more likely to report lost wallets with money than without". This effect was even more pronounced when the amount of money was increased sevenfold.

Confounded by these findings, the researchers controlled for competing interpretations and other variables, such as fear of being identified and getting in trouble. In doing so they found that the presence of a key, something valuable to the wallet's owner but useless to the "finder" of the wallet, also increased the likelihood of the wallet being returned.

"Taken together," Shalvi writes, "these results support the idea that people care about others as well as caring about being honest."

The results are surprising. As part of the research, the team also surveyed the expectations of lay people and economists and found that they both predicted the exact opposite pattern of results in surveys reported by the authors.

Cohn and colleagues use these unexpected results to frame civic honesty in a new way by identifying four key elements: "(i) the economic payoff of keeping the wallet, (ii) the fixed effort cost of contacting the wallet's owner, (iii) an altruistic concern for the owner's welfare, and (iv) the costs associated with negatively updating one's self-image as a thief."

In this framework, these four elements interact to produce behaviour with the novel finding being that the psychological cost of viewing oneself as a thief can often outweigh any economic benefit.

Shalvi sees the work as important for understanding how to design social and organisational environments that promote socially desirable behaviour.

For the rest of us, perhaps we can be slightly less worried next time we lose our loaded wallets.