Casting light on cheating and greed

Louis Brandeis was already one of America’s most famous lawyers when Woodrow Wilson appointed him to the Supreme Court in 1916. He was a tireless and prescient critic of big investment banks—including bankers’ excessive bonuses—an argument he spelled out in his influential book of essays, Other People’s Money and How Bankers Use It. His solution for the problem of concentrated financial power was unfettered public scrutiny, a belief he summarized in his famous statement: “Sunlight is said to be the best of disinfectants; electric light the most efficient policeman.”

Justice Brandeis was an intuitive psychologist. When he said that the “broad light of day” would purify men’s actions, he was anticipating a field of research that is just now beginning to illuminate the intricate interplay of the mind, the body, and morality. Light, it appears, does much more than distinguish day from night; it takes away our illusion of anonymity and, in doing so, literally keeps us honest.

This seems obvious on one level. Streetlights were most likely invented to deter crime, and big power outages are almost inevitably followed by looting. But darkness in that sense is actual cover for criminals, like a mask. The new research suggests that even non-criminals may be influenced by the metaphorical meaning of light and darkness, becoming more dishonest and self-centered as light diminishes.

Here’s the science. Three psychologists—Chen-Bo Zhong and Vanessa Bohns of the University of Toronto and Francesca Gino of the University of North Carolina—wanted to explore the idea that metaphorical darkness leads to illusory anonymity, and in turn to moral transgression. In one experiment, they had a group of volunteers perform a complicated mathematical task—so complicated that it was impossible to complete in the time allotted. When they ran out of time, the volunteers were told to pay themselves only for the work they were able to finish. This was all done anonymously, although secretly the scientists were monitoring the volunteers’ actions.

Half the volunteers did this sham exercise is a brightly lit room, with twelve overhead light bulbs, while the others did it in a room dimly lit by just four bulbs. The idea was to see if those in the darker room were more likely to cheat than those working in bright light. And they were, indisputably. They not only lied about their performance on the difficult task, they also paid themselves more cash for work they had failed to do. In short, they lied, cheated and stole money.

It’s important to note that, while one room was darker than the other, neither room was actually dark. That is, the lack of illumination was not enabling the cheating; and indeed, the task was (ostensibly) anonymous anyway, so there was nothing really to hide. It’s not like they were tip-toeing out of the room with cash. Yet the dim lighting gave volunteers the psychological license to behave unethically.

These findings were bizarre enough that the scientists wanted to double-check them. So in a second experiment, instead of dimming the room, they had only some of the volunteers wear sunglasses to dim their view. Then all the volunteers participated in a laboratory exercise called the dictator’s game. The dictator’s game is a test of fairness and greed; one volunteer (the initiator) has a given pot of cash, and is allowed to give away all, some or none of it to another, who can accept or reject it. In this experiment, all the volunteers were initiators; the scientists simply wanted to see how generous or stingy they were, depending on whether they were wearing sunglasses or not.

Shades corrupt. As reported on-line in the journal Psychological Science, those with a slightly darkened view of the world gave away considerably less money—less than what’s fair and less than the volunteers not wearing shades. Darkness gave them the sensation that they were more concealed, and that in turn made them greedier people.

Think about this for a minute. The researchers were not manipulating light and darkness so that some actually had more cover. They were the ones perceiving a darker world, and that perception was enough to license their transgressions. What’s going on here? Well, the researchers believe that dimming the lights or wearing sunglasses is a kind of egocentric mental “anchor”; because they see the world as somewhat darkened, they assume that others have an obscured view of them as well. They act not as if they have sunglasses on, but as if there has been a widespread power outage that has darkened everyone’s world.

Kids are notoriously egocentric in this way. They’ll close their eyes when they play hide-and-seek, thinking that they can’t be seen if they themselves can’t see. Apparently, adults don’t outgrow this egocentrism entirely. But what’s cute in a childhood game of hide-and-seek isn’t nearly so cute in grownup games with other people’s money.

For more insights into the quirks of human nature, visit the “Full Frontal Psychology” blog at True/Slant. Excerpts from “We’re Only Human” appear regularly in the magazine Scientific American Mind. Wray Herbert’s book, On Second Thought: Outsmarting Your Mind’s Hard-Wired Habits, will be published by Crown in September.


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