YOUR INNER SADIST: THE NEUROSCIENCE OF EVIL

On pain, pleasure and psychopathy

When We Talk about evil we tend to turn our attention to Hitler. This is perhaps unsurprising, as Hitler perpetrated many of the acts that we associate with evil, including mass murder, destruction, war, torture, hate speech, propaganda and unethical science. History, and the world, will forever be stained with his memory.

A nod to the pervasiveness of our automatic connection between general badness and Hitler is even reflected in everyday human interactions. In disparaging discussions, people who say or write things that others disagree with are often described as 'Nazis' or 'like Hitler'. Godwin's Law suggests that every online comment thread will eventually lead to a Hitler comparison. These in-passing comparisons trivialise the atrocities committed, escalate discussion to a point of no return, and often effectively shut down conversation. But, I digress.

Because of the variety and depth of the devastation Hitler was both directly and indirectly responsible for, entire books have been written about his motivations, his personality and his actions. People have long wanted to know why, and how, he became the man we know from the dark pages of our history books. In this chapter, instead of dissecting the particulars of his actions, I want us to focus our attention on just one question: if you could go back in time, would you kill baby Hitler?

The answer to this one question tells me a lot about you. If you answer 'yes', then you probably believe that we are born with the predispositions to do terrible things. That evil can be in our DNA. If you answer 'no', then you probably have a less deterministic view of human behaviour, perhaps believing that environment and upbringing play a critical role in how we end up as adults. Or, perhaps, you said 'no' because killing babies is generally frowned upon.

Either way, I think that the answer is fascinating. I also think that it is almost certainly based on incomplete evidence. Because do you really know whether terrible little babies become terrible adults? And is your brain actually that different from Hitler's?

Let's do a thought experiment. If Hitler was alive today, and we put him into a neuroimaging scanner, what would we find? Would there be damaged structures, overactive sections, swastika-shaped ventricles?

Before we can reconstruct his brain, we need to first consider whether Hitler was mad, bad or both. One of the first psychological profiles of Hitler was written during World War II. It is considered to be one of the first offender profiles ever, and was written by psychoanalyst Walter Langer in 1944 for the Office of Strategic Services, a US intelligence agency and early version of what would later become the Central Intelligence Agency.

The report described Hitler as 'neurotic', that he was 'bordering on schizophrenia', and made the correct predictions that he was striving for ideological immortality and would commit suicide in the face of defeat. However, the report also makes a number of pseudo-scientific assertions that are unverifiable, including that he enjoyed masochistic sex (being hurt or humiliated) and had 'coprophagic tendencies' (the desire to eat faeces).

Another attempt at a psychological profile was published in 1998, this time by psychiatrist Fritz Redlich. Redlich conducts what he refers to as a pathography – a study of the life and personality of a person as influenced by disease. In studying Hitler's medical history and the medical history of his family, along with speeches and other documents, he argues that Hitler showed many psychiatric symptoms, including paranoia, narcissism, anxiety, depression and hypochondria. However, although he finds evidence for so many psychiatric symptoms that he 'could fill a psychiatry textbook', he argues that 'most of the personality functioned more than adequately' and that Hitler 'knew what he was doing and he chose to do it with pride and enthusiasm'.

Would he have wanted to kill baby Hitler? Or would he have placed more importance on Hitler's upbringing? Redlich argues that there was little to suggest during childhood that Hitler would become a notorious, genocidal politician. He argues that, medically speaking, Hitler was a fairly normal child, who was sexually shy and did not like torturing animals or humans.

Redlich also argues against the idea that little Hitler had a particularly troublesome upbringing, and criticises psycho-historians for assuming that he did. It seems that we cannot assume this to be the cause of his later behaviour, and the unsatisfying answer to whether Hitler was mad seems to be 'no'. It turns out that this is often the case. Just because someone has committed heinous crimes does not mean that they are mentally ill. To assume that everyone who commits such crimes is mentally ill removes personal responsibility from the perpetrators of such acts, and stigmatises mental illness. So, how are people like Hitler capable of such horrors?

Working towards a 'neuroscience of human evil', psychological scientists Martin Reimann and Philip Zimbardo came up with a different idea as to why we are capable of horrible acts. In their 2011 paper, 'The Dark Side of Social Encounters', the authors try to establish what parts of the brain are responsible for evil. They state that two processes are most important – deindividuation and dehumanisation. Deindividuation happens when we perceive ourselves as anonymous. Dehumanisation is when we stop seeing others as human beings, and see them as less than human. The authors also explain dehumanisation as a 'cortical cataract', a blurring of our perception. We stop being able to really see people.

This is apparent when we talk about 'the bad guys'. The statement dehumanises. It assumes that there is some homogenous group of individuals who are 'bad', and who are different from us. In this dichotomy, we, of course, are the 'good guys' – a diverse group of human beings who make ethically sound decisions. This dividing of the world into good guys and bad guys was one of Hitler's preferred approaches. Even more distressing was the development of the argument that those targeted were not even made up of 'bad people', that they were not even human. A dramatic example of dehumanising was seen in Hitler's genocidal propaganda, where he described Jewish people as...