Anybody and everybody can turn into a perpetrator of evil.

Look back on your life. Have you ever taken something that wasn’t yours when no one was watching? Most people have. Though not the greatest of evils, this kind of petty theft nonetheless says something about our willingness to do things we wouldn't normally do if the context or situation allows for it.

And yet, we still cling to the notion that some people are just born evil, while others are born saints. The truth, however, is that the line separating good from evil is exceedingly permeable.

Take, for example, the case of Ivan “Chip” Frederick, a former staff sergeant in the US Army. He was one of the guards at Abu Ghraib prison, which gained worldwide attention in 2003 for the abuse and torture of Iraqi prisoners held there.

Was Frederick a bad person before his tenure at Abu Ghraib? No – quite the contrary. He was a surprisingly normal, patriotic, baseball-loving young man from Virginia, whose psychological assessments yielded an average IQ and no signs of psychopathological traits whatsoever. But in the Abu Ghraib prison, he transformed into a cruel sadist.

What could cause this drastic change in behavior?

When people commit evil deeds, we often assume that those people are evil-natured. So when something like Abu Ghraib happens, we tend to point the finger at individuals. Traditional psychiatry takes the same view.

Psychiatrists and psychologists like to focus on what's called dispositional causes, i.e., inborn traits that cause our behavior. Genetics, character, pathologies – it’s believed that we carry these attributes with us.

In Frederick’s case, people cited dispositional causes – he was born a sadistic monster – to explain his actions. But there were indeed situational causes that were more responsible for his behavior than whatever character traits he was born with.

As you’ll discover in our next blink, Frederick wasn’t born good or evil. The real causes of evil behavior lie somewhere else entirely.