As they hovered over their victims, knives at the ready, Carney Landis issued his instructions. The beheading was ready to commence.
It was 1924 and this particularly sadistic grad student had lured an assortment of fellow pupils, teachers and psychology patients – including a 13-year-old boy – into a room at the University of Minnesota.
To put his subjects at ease he had redecorated, concealing laboratory equipment, draping cloth over the windows and hanging paintings on the walls.
Landis wanted to know if certain experiences, such as pain or shock, always elicited the same facial expressions. And he was prepared to inflict them in order to find out. He sat his subjects down in comfortable chairs, then painted lines on their faces so that he could better see their grimaces.
Over the course of three hours, they were repeatedly photographed while being subjected to a series of bizarre and unpleasant pranks, including placing fireworks under their seats and electrocuting their hands while they felt around in a bucket of slimy frogs. The climax came when he fetched a live white rat on a tray and asked them to cut off its head with a butcher’s knife.
Landis’ methods were certainly unethical, but perhaps the most uneasy revelation was what he discovered. Even during the most violent tasks, the most common reaction wasn’t to cry or rage – it was to smile. He wrote: “So far as this experiment goes I have found no expression other than a smile, which was present in enough photographs to be considered as typical of any situation.”
What was going on?
Fast-forward to 2017 and we’re head-over-heels for this simple reflex. Today reminders to ‘smile’ are ubiquitous, printed on fridge magnets, adverts, self-help books and occasionally hurled at us by well-meaning strangers. Those who smile often are thought of as more likeable, competent, approachable, friendly and attractive.
But the truth is far more sinister. Of 19 different types of smile, only six occur when we’re having a good time. The rest happen when we’re in pain, embarrassed, uncomfortable, horrified or even miserable. A smile may mean contempt, anger or incredulity, that we’re lying or that we’ve lost.
While genuine, happy smiles exist as a reward for when we’ve done something helpful to our survival, the ‘non-enjoyment’ smiles are less about what you’re feeling inside and more about what you want to signal to others. “Some evolved to signal that we’re cooperative and non-threatening; others have evolved to let people know, without aggression, that we are superior to them in this present interaction,” says Paula Niedenthal, a psychologist at the University of Wisconsin-Madison.
Many are polite gestures which demonstrate that we’re following the rules. But they can also be an effective way of manipulating others or distracting them from our true feelings. More often than not, the universal symbol of happiness is used as a mask.
The first steps to decoding this multi-purpose expression came from the 19th Century neurologist Duchenne de Boulogne. He was the son of a French pirate and had a penchant for electrocuting his patients – among other things, he was a founding father of electrotherapy. Duchenne was interested in the mechanics of facial expressions, including how the muscles of the face contract to produce a smile. The best way to study this, he decided, was to attach electrodes to a person’s face and jolt their muscles into action.