Can evolutionary psychology explain why we love to hate evil villains?

By guest blogger David Robson

Darth Vader. Hannibal Lecter. Lord Voldemort. In literature and in film, it's often the villains who steal the show. In John Milton's Paradise Lost, the beautiful, charming Satan even manages to upstage God. No matter how diabolical their schemes are, we seem to have an unnerving fascination with the wicked.

Why are our stories filled with these vile characters, people so evil that we love to hate them? While the question has long been debated by literary scholars, a new paper published in Evolutionary Behavioural Sciences by Jens Kjeldgaard-Christiansen at Aarhus University in Denmark is the first to cast light on these shadowy figures through the prism of evolutionary psychology.

To understand the appeal of evil, Kjeldgaard-Christiansen argues that you first need to examine its opposite – altruism. In our evolutionary past, individuals living in tight-knit groups needed ways of working out who was pulling their weight and punishing those who didn't. Today, we continue to make these value judgments using gut reactions rather than deliberate, rational thinking, normally based on a calculation of how much a person is willing to sacrifice for the overall good of the group (the so-called "welfare trade-off ratio"). Someone with a low welfare trade-off ratio, who gives little (or nothing) but takes a lot, immediately rings our brains' alarm bells, telling us that they are not to be trusted.

Clearly, keeping these people in our groups would have put us all in danger so they provoke the most potent emotional responses, such as disgust, fear and anger. Our reactions may be so strong that we may even feel justified in killing them to remove the threat from society. It is these people we consider "evil". Importantly, these intuitions are hunches and can be easily swayed by a number of factors. For example, there is research showing that physical disgust (fear of illness, say) can spill over and influence our moral decisions. Crucially, Kjeldgaard-Christiansen says authors can and do make the most of these kinds of features to build the most spine-chilling villains.

Kjeldgaard-Christiansen predicts a handful of qualities that his evolutionary approach says should characterize the most iconic villains. It goes without saying that they should have a particularly low "welfare trade-off ratio", for instance – but it also makes evolutionary sense if there is a threat that their immoral behaviour could spread like a disease in society more generally. Supporting this idea, he quotes Father Merrin from The Exorcist, who said: "I think the demon's target is not the possessed; it is us . . . the observers . . . every person in this house. And I think—I think the point is to make us despair; to reject our own humanity." This perfectly fits a very real threat in our ancestral past – that one unpunished act could sow the seeds for wider anarchy.

To heighten the instinctive fear response in readers, Kjeldgaard-Christiansen says the author may also choose to maintain a cloak of mystery around the villain; after all, if we know too much about their motives, we may stop feeling that intuitive, impulsive revulsion and instead see their point of view. The trick with someone like Hannibal Lecter, then, is to make them just psychologically deep enough to be believable, without bursting the disconcerting aura of evil. What's more, the most evil villains will also be marked as outsiders, since strangers from competing groups were the biggest threat in our past – the reason, perhaps, that so many Hollywood villains (including Hannibal) have a foreign, often English, accent.

Pointing to the aforementioned research on disgust, Kjeldgaard-Christiansen also believes it is no coincidence that fictional villains are often deformed – like Leatherface in The Texas Chainsaw Massacres – somehow, our revulsion at their appearance primes us to feel repelled not just physically but morally too. "His brutish roars and apish gait warn the viewer that something is very wrong with this iconic recluse. Leatherface's foul exterior becomes the manifestation of a foul essence," writes Kjeldgaard-Christiansen. The same could equally be said about Lord Voldemort's mutated, foetal appearance in Harry Potter, or the scars on Javier Bardem's Raoul Silva in Skyfall.

Far from being escapist titillation, Kjeldgaard-Christiansen thinks that creating these tales may in fact have an evolutionary purpose. Taking these short trips into the dark sides of our natures, and seeing good triumph over evil, helps us to reaffirm our altruistic tendencies, leading to better cooperation overall.

It's an intriguing idea – and it would be interesting to see if Kjeldgaard-Christiansen can test his theory. You can imagine that he could show participants an extract from Hannibal, say, and then ask them to play games (such as the Prisoner's Dilemma) that involve cooperation in the lab, to see if they are more likely to play fairly.

If so, it will add to a growing body of work exploring the ways that fiction can shape our behaviour: for example, some fascinating work by Travis Proulx at Tilburg University has shown that absurdist authors such as Franz Kafka or Lewis Carroll, whose stories violate the laws of the real world, can have an unsettling effect, leading us to look for confirmation of our existing beliefs. We also know that urban legends that break taboos (such as incest) appear to be more widely shared than those that are simply disgusting or frightening – which some researchers believe may reflect the evolutionary role of story-telling as a means of teaching social norms.

Censors sometimes worry that depictions of evil will lead us all the way of the devil. In fact, If Kjeldgaard-Christiansen is right, the opposite may be true: by making us peer into the darkness, these villains may just make us better people.

Further reading

Kjeldgaard-Christiansen, J. (2015). Evil Origins: A Darwinian Genealogy of the Popcultural Villain. Evolutionary Behavioral Sciences DOI: 10.1037/ebs0000057

About the author

Post written by David Robson (@d_a_robson) for the BPS Research Digest. David is BBC Future's feature writer.