That feeling of revulsion, even fear, that assaulted Freud at the moment of seeing his own reflection in that split-second before his mind processed it and understood it for what it was, is called by Freud the uncanny, a sense of existential wrongness that arises when a thing that should be familiar, safe and banal is suddenly taken out of context.
In 1970, Japanese roboticist Masahiro Mori came upon the uncanny without having familiarized himself with Freud at all. He observed that something about lifelike animatronic machines and robots made people feel ill at ease, and came up with a model to explain this feeling: endowing objects with human features makes them feel more familiar and safer to us - up to a certain point. At some point, when a thing is too similar to a human, those things that seem inhuman about it scream out to us in contrast.
It is why, when looking at a walking and talking robot that was designed to look like a human, we get the profound sense that something is off about it, and it scares us.
Mori’s model was, however, just a hypothesis until a team of neuroscientists decided to put it to the test: they asked test subjects to rate certain images of people and robots in terms of likeability and trustworthiness, and found that the most humanlike robots were deemed the least likable and trustworthy, a feeling that was rooted in the VMPFC, the region in our brain tied to processing fear and risk-calculation. In other words, Mori was right.
But robots are not the only thing that triggers this uncanny feeling in us. Think about seeing a human corpse: it looks like a human, it used to be a human, but it does not function as a human should. Now, take that corpse through a second metamorphosis, put it on its feet and make it shuffle and lumber about, and you’ve got the stuff of nightmares.
And it’s not just apparitions, zombies and androids that make us tremble with unease; humans can make us feel this way, too. Silent-era horror actor Lon Chaney is quoted as having said, “there’s nothing funny about a clown in the moonlight”, and if you doubt the potential of buffoons to terrify, just look at the recent craze of people dressing up as machete-wielding clowns.
But why do clowns scare us so much? Disregarding costumes that are meant to be frightful, modern-day clowns are dressed in garish clothes, move in exaggerated motions, speak in a childish way while inhabiting the body of an adult (or even worse- don’t speak at all), are constantly smiling (imagine a normally-dressed person with a perpetual grin and tell me that isn’t an unsettling thought) and have a face that is painted white like a corpse. All of these distinctly unnatural attributes come together in what is sometimes called coulrophobia (fear of clowns), and it is very clearly rooted in that same uncanny feeling that makes us cringe at robots.
That uncanny feeling can, for the most part, be contained within a proper context. Seeing a clown performing in a circus may not trigger this fear while seeing him standing in an alley at night will. Going to an open-casket funeral where you expect to see a dead body may not rattle you so much, but, just like in the case of Freud seeing a familiar image and not being able to immediately place it is precisely when the thing appears to us without context, “in the moonlight” as it were, that it scares us.