The Science of Evil

Click here to read an original op-ed from the TED speaker who inspired this post and watch the TEDTalk below.

Phil Zimbardo's TEDTalk on evil is a terrific example of how to give a good TEDTalk, and a terrific example of the situationist explanation for how ordinary people do 'evil' things under the wrong conditions. These conditions, according to Zimbardo, include anonymity (e.g., when soldiers wear uniforms), obedience to an authority figure who says they will take responsibility, being given power to use and abuse, and the absence of any moral spotlight to supervise what people are up to. Zimbardo is no doubt right that such situational factors can turn "good apples" into "bad apples" and -- in his metaphor -- how one needs to look at the "bad barrel" to explain how people cross the line from being a good person to a bad person.

Zimbardo uses the term 'evil' but I prefer a different term, the 'erosion of empathy', because whilst the word 'evil' is used as if it is an explanation ("He did X because he is evil"), in fact evil is just a word meaning "the absence of good", getting us into a dangerous circularity ("He did X because he is not good"). The term 'evil' doesn't take us any further forward. In contrast, the concept of empathy (or its erosion, by degrees) has explanatory power, because empathy can be measured and analysed scientifically in terms of the factors that influence how much empathy each of us has. Even more usefully, empathy is normative, meaning we don't just have to focus on the extreme negative end of human behavior. We can consider the whole spectrum, from cruelty through to kindness, and every shade in between.

I enjoyed Zimbardo's TEDTalk not just because it was packed full of interesting photography and footage, but also because of the personal anecdotes: How Zimbardo was in the same high school class as Stanley Milgram, who ran the other world-famous social psychology experiment to explain cruelty. And how the young female whistle-blower in the Stanford Prison Experiment, who persuaded Zimbardo to stop the experiment because it was damaging the young volunteer-prisoners, later became his wife!

Equally uplifting was how Zimbardo now uses his same situationist approach to explain what he neatly calls "the banality of heroism," adapting Hannah Arendt's chilling phrase "the banality of evil," to argue that ordinary people can choose the path of helping someone or can simply be passive and let bad things happen. He picks out Wesley Autrey as an example of an ordinary hero. This was the black construction worker who saw a young white student having an epileptic fit, causing him to fall onto the train tracks as a New York subway train was approaching. Wesley gave his two young daughters to a stranger to look after, and made a split-second decision to dive onto the train track, cover the epileptic student with his body, holding him against the ground, allowing the train carriages to pass over them both, and missing his head by just half an inch.

Missing from Zimbardo's account is any reference to the individual factors that interact with such situational ones that make one person conform to socially sanctioned group violence, and make another person resist the conformity bias and stand up for what he or she thinks is right. - Simon Baron-Cohen

But whilst I applaud Zimbardo for keeping alive the situationist theory of cruelty for over four decades, I think the theory is a product of its time. When the Stanford Prison Experiment was conducted, in 1971, it was fashionable to 'blame' the ills of the world on 'the system' (our social institutions).

Missing from Zimbardo's account is any reference to the individual factors that interact with such situational ones that make one person conform to socially sanctioned group violence, and make another person -- in the very same situation -- resist the conformity bias and stand up for what he or she thinks is right. Zimbardo hints at individual factors when he says we each have a "choice" to do the right thing or not, but that does not take us very deep and again is even a little circular. We cannot explain cruelty or kindness simply as the result of making choices, since what we are trying to explain is why people make the choices they do.

Research over these last four decades has isolated a number of factors that bias individuals in one direction or another. The first is the quality of attachment in early experience. Research into adults with personality disorders reveal high rates of abuse and emotional neglect in their early childhoods, suggesting that it is the experience of being cared for as an infant and toddler that influences one's capacity to care about others in later life.

Early experience can't be the whole story, since not everyone who has a bad childhood ends up showing cruelty to others, and some psychopaths had perfectly loving parents and still ended up capable of hurting others. This means we have to turn to biology. Research again points to our genes influencing our risk for developing antisocial personality traits. For example, Avshalom Caspi and colleagues found that which version of the MAO-A gene you carry affects your risk of ending up with a diagnosis of "conduct disorder" or delinquency in adolescence. Most interesting, this genetic variant interacts with whether a person experienced abuse or neglect in their childhood, demonstrating that genes interact with environment.

And a second biological factor that influences later empathy is the prenatal sex steroid hormone testosterone. How much of this hormone the fetus is exposed to shapes the development and function of the 'empathy' circuit in each of our brains. My own TEDx talk acknowledges the major contribution of Zimbardo's and Milgram's social psychological theories of cruelty, but reminds us that we need to understand its neurobiological and developmental psychological roots too.

Simon Baron-Cohen is author of The Science of Evil (Basic Books) and is Professor and Director of the Autism Research Centre, Cambridge University.

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