Are terrorists ‘evil’? Philip Zimbardo and the darkness within us all

On November 13th 2015, Omar Ismael Mostefai detonated an explosive belt at the Bataclan Theater in Paris, killing 89 people. The French national had returned to his home city to carry out the attack after a brief stint as a jihadist in Syria the year before. Yet police investigations suggested he was an ‘ordinary person’ – a married father who had never spent time in jail. One of his neighbors even described him as “a really great guy; friendly; open.”

During World War II, Adolf Eichmann helped organize the murder of more than six million Jews. When Israeli secret service finally captured the once widely-feared Nazi leader in Argentina in 1960, six psychologists concluded that, despite overseeing the largest genocide in history, Eichmann was perfectly sane (or “terrifyingly normal,” as political theorist Hannah Arendt puts it).

Examples of supposedly good people doing bad things appear time and time again in history. But how can healthy people commit such violence? Eichmann’s own response to this question is chillingly straightforward: “I merely obeyed orders, and surely obeying orders could only be a good thing.”

But this explanation will never answer the questions that psychologists really want to resolve: What makes people do evil things? Is evil an innate condition, or do environments and group pressures combine to condition evil acts like violence?

Understanding evil isn’t easy, even with the help of great thinkers like Eric Hoffer and Friedrich Nietzsche. Butin 1971, American psychologist Philip Zimbardo set out to crack the problem for good.


From college students to college sadists

Zimbardo set up a mock jail in a Stanford University basement, dividing 24 clinically-sane students with no prior criminal history into two groups: guards – wearing police uniforms and carrying clubs, whistles, and handcuffs – and prisoners – who police ‘arrested’ at their homes and brought into custody.

The psychologist’s intention was to observe the groups’ behavior over a fourteen-day period. But he was forced to suspend the experiment after six: guards became so violent that half of the prisoners suffered emotional breakdowns. The fact that guards became so aggressive and prisoners so submissive didn’t really surprise Zimbardo (in fact, this is what he’d hypothesized). But the increasingly dangerous tactics some guards used, such as stripping the prisoners naked and not allowing them to use the toilet, shocked him. These episodes occurred mostly at night when guards thought the prison’s security cameras had been turned off.

The guards’ behavior corresponded to Zimbardo’s own definition of evil; the use of power to “intentionally harm (psychologically), hurt (physically) and/or destroy (mortally) and commit crimes against humanity.” He identifies a series of elements that condition such behavior. They bear a striking resemblance to the cases of the Nazi Adolf Eichmann and terrorist Omar Ismael Mostefai, as well as the guards at Stanford.


Zimbardo's path to evil

The experiment was an important breakthrough. Whereas other psychologists, such as Freud, had focused on the complexities of the human mind, Zimbardo showed that situational and systemic forces could quickly transform good, educated people into evildoers.


Abu Ghraib: the Stanford Experiment becomes reality

In 2003, images on TV revealed the Stanford Experiment was no longer merely an experiment; strikingly similar actions were taking place at Abu Ghraib, an Iraqi jail holding suspects seized during the American ‘War on Terror.’ This provoked Zimbardo to write The Lucifer Effect: How Good People Turn Evil (2007).

The title of the text refers to the Bible verse in which Lucifer, God’s favorite angel, is cast from heaven to hell for his disobedience and transformed into the Devil. It shows there is no simple distinction between good and evil: normal soldiers can commit horrible acts when the combination of elements Zimbardo identifies fall into place.

While some government and military officials attributed the humiliation and violence at Abu Ghraib to a few “bad apples” or “rogue soldiers,” and promised swift legal action against them, Zimbardo knew from experience that the problem would run much deeper.

Through his writings, and testimony in one of the court hearings, he argued that, in addition to holding the soldiers in question accountable for their actions, the higher authorities who encouraged and allowed these acts to occur should also be prosecuted. Indicting only the soldiers, Zimbardo said, is “like putting on trial the hit man for the Mafia and not the Mafia bosses.”


The Stanford Experiment today

The Stanford Experiment remains a staple in the field of psychology and its findings can be applied to a wide range of issues, from bullying in schools to terrorist attacks by Islamic State.

In interviews, Zimbardo has addressed terrorism explicitly, criticizing politicians such as former American president George W. Bush who draw clear lines between “good” and “evil.” Instead, Zimbardo encourages us to consider how situational and systemic forces can turn a normal person into a sadistic perpetrator of evil. In particular, he has tried to understand why seemingly ordinary people, like Mostefai, join terrorist groups, and how propaganda peer group pressure can condition their subsequent behavior.

Zimbardo believes alienated young men join terrorist groups out of a need to experience a sense of belonging, acceptance, and respect. Due to the groups’ recruiting and propaganda power, some individuals’ empathy erodes. They become radicalized and commit atrocities that conform to social pressures and bring approval from peers.

In interviews, Zimbardo also insists we need to openly acknowledge “the dark side of religion” – that is, “how religiously based value systems can be perverted to justify and reward the most horrendous of human deeds” – as when ISIS claimed responsibility for the Paris attacks.


What lessons can we learn from Zimbardo?

Philip Zimbardo quote

Zimbardo encourages us to look beyond individual responsibility and examine the situational and systemic conditions that shape individual shifts from good to evil. By doing so – he argues – we can better understand the actions of people like Eichmann and Mostefai. Some psychologists criticize his work, arguing he should pay closer attention to human nature and individual differences. Zimbardo counters by insisting: “If you put good apples into a bad situation, you’ll get bad apples.”

Despite this criticism and others, psychologists generally agree external factors and social pressures play a critical role in shaping evil behavior. Zimbardo’s work on Abu Ghraib and terrorism is important because it encourages us to refrain from drawing simple conclusions. In the case of the Iraqi prison, he argues both soldiers and higher authorities should be held accountable. In the case of terrorism, he encourages us to examine the root causes and group pressures that cause it.

Finally, as Zimbardo suggests, the evidence indicates that there really is a fine line between good and evil. Under certain conditions, we are all capable of committing sinful acts – we are all vulnerable to the dark side.


Get a deeper understanding of Zimbardo’s ideas:

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