“The line between good and evil is permeable,” said psychologist Philip Zimbardo, “and almost anyone can be induced to cross it when pressured by situational forces.”
As Zimbardo and other social scientists have shown in a range of experiments, actions we deem evil — cheating, lying, stealing, and worse — don’t spring from people’s character, but the situations they find themselves in.
To better understand why, we examined research from the fields of psychology and ethics. Here’s what we found.
Max Nisen and Aimee Groth contributed to this story.
Philip G. Zimbardo, professor emeritus of psychology at Stanford University, argues that people do evil things when they have an ideology -- or system of ideals -- to lean on.
He was an expert witness during the trial of U.S. Army Staff Sgt. Ivan 'Chip' Frederick, who was sentenced to eight years in prison after pleading guilty to five charges of abusing prisoners in Abu Ghraib.
'All evil begins with a big ideology,' Zimbardo said. 'What is the evil ideology about the Iraq war? National security. National security is the ideology that is used to justify torture in Brazil. You always begin with this big, good thing because once you have the big ideology then it's going to justify all the action.'
Zimbardo is best-known for leading a jail simulation in 1971, popularly known as the Stanford Prison Experiment.
In the experiment, college students played the roles of 'prisoners' or 'guards.'
In only six days, the 'guards' were so abusive toward their 'prisoners' that Zimbardo had to end the experiment early.
'The experiment showed that institutional forces and peer pressure led normal student volunteer guards to disregard the potential harm of their actions on the other student prisoners,' the American Psychological Association reports.
If people wear a uniform, hood, or mask, they feel more anonymous -- and more comfortable with being cruel.
People can get more aggressive when they feel anonymous, Zimbardo continued.
When identities are concealed, violence increases. 'You minimize social responsibility,' Zimbardo said. 'Nobody knows who you are, so therefore you are not individually liable. There's also a group effect when all of you are masked. It provides a fear in other people because they can't see you, and you lose your humanity.'
Anonymity also contributes to the viciousness of internet commenters, social scientists suggest.
Setting and achieving goals is important, but single-minded focus on them can blind people to ethical concerns.
When Enron offered large bonuses to employees for bringing in sales, business ethics professor Muel Kaptein argues, they became so focused on that goal that they forgot to make sure they were profitable or moral.
In large organisations, employees can begin to feel more like numbers or cogs in a machine than individuals.
Kaptein says this can lead to unethical behaviour. When people feel detached from the goals and leadership of their workplace, they are more likely to commit fraud, steal, or hurt the company via neglect.
Psychology research shows that when people take a broad posture, they feel more powerful. But there's a dark side to the 'power pose': MIT professor Andy Yap found that the feeling of power you get from taking a broad stance can not only make you behave more assertive but also more likely to cheat.
'If you take an expansive pose, it can actually lead to power,' he tells Business Insider. 'Postures are incidentally related to power, and one of those behaviours is dishonest behaviour.'
In a series of experiments, University of Washington Professor Christopher Barnes found that people have less ability to exercise self-control when they're tired.
Which means that when they haven't slept enough -- typical of 26% per cent of Americans -- they're more likely to cheat.
'Organisations need to give sleep more respect,' Barnes writes. 'Executives and managers should keep in mind that the more they push employees to work late, come to the office early, and answer emails and calls at all hours, the more they invite unethical behaviour to creep in.'
Former New York City Mayor Rudy Giuliani popularised the 'broken window theory' when he led a sweeping effort to lower crime rates. The idea was to crack down on smaller, petty crimes, and clean up the city to create some semblance of order, and discourage larger crimes.
When people see disorder or disorganization, they assume there is no real authority. In that environment, the threshold to overstepping legal and moral boundaries is lower.
When people feel like they have been ethical for a long time, they will want to 'cash in' on that positive behaviour.
Sometimes moral people feel like they have collected 'ethical credit' that they can use to justify immoral behaviour.
This comes from the work of University of Toronto psychologists Nina Mazar and Chen-Bo Zhong, who found that people who have just bought sustainable products may be more likely to lie and steal afterwards than those who bought standard versions.
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