October 31st is the day when we revel in all things creepy. Children roam the streets, seeking treats, undeterred by leering, demonic-looking Jack-o’-lanterns, plastic skeletons, and other pieces of Halloween paraphernalia. And later on, when the stream of trick-or-treaters has dried up, and the kids are tucked away in bed, the adults might celebrate by sitting down to watch a horror movie.

Horror movies aren’t the same as scary movies. The plots of scary movies are riddled with physical danger. Silence of the Lambs is unquestionably a scary movie, but it’s not a horror movie. Fear morphs into horror only when it’s supplemented by an element that I call metaphysical threat. Metaphysically threatening things leave us with a deep, nightmarish sense of disorientation, driving home the unsettling idea that we can’t rely on the ordinary framework of assumptions that give us a sense of security.

The British horror writer Arthur Machen captured the essence of metaphysical threat perfectly in his novel The House of Souls. “What would your feelings be,” a character asks, “… if your cat or your dog began to talk to you, and to dispute with you in human accents?” He continues, “You would be overwhelmed with horror. I am sure of it. And if the roses in your garden sang a weird song, you would go mad. And suppose the stones in the road began to swell and grow before your eyes, and if the pebble that you noticed at night had shot out stony blossoms in the morning?”

The philosopher Noël Carroll points out in his book The Philosophy of Horror that when metaphysical threat (or, as he calls it, “cognitive threat”) is combined with physical threat, something monstrous emerges. Monsters have got to be physically menacing—a monster that can’t or won’t hurt anyone isn’t a monster at all. But simply being dangerous in that way doesn’t distinguish monsters from other threatening entities, like grizzly bears and serial killers. Horrific monsters have got to be metaphysically threatening too.

What gives monsters their metaphysically ominous aura is that they are fusions of incompatible kinds of things, and therefore do violence to our conceptions of the natural order. Like Machen’s singing roses—which are an unsettling combination of the human (singing) and the botanical—monsters transgress the boundaries of what philosophers call natural kinds. For example, some of them (zombies) are alive and dead at the same time. Others, for example werewolves, are human/animal fusions. Chucky, from Child’s Play, is an animate doll. All of these entities, and others from horror fiction, are both dangerous (in fact, deadly) and also unnatural.

We enjoy horror flicks because we know the horror isn’t real. The monsters are all make-believe monsters. But the idea that there are real monsters was and is regarded by many people with deadly seriousness, and not just by those who are shrouded in superstition. These aren’t monsters like Freddie Kruger, Count Dracula, and their ilk, but they’re monsters nonetheless.

I’m talking here about dehumanized people—members of oppressed and marginalized groups who are regarded by their tormentors as subhuman creatures. And when dehumanized people are seen as physically threatening, the stage is set for morphing them into monsters. In Nazi discourse, Jews were described not only as Untermenschen (subhumans), they were also portrayed as irredeemably destructive. Consequently, anti-Semitic propaganda from the Third Reich often reads like a horror narrative. For example, a widely circulated 1942 booklet published by Hitler’s SS entitled The Subhuman states:

This subhuman hates all that is created by man. This subhuman has always hated man, and always secretly sought to bring about his downfall…. The subhuman thrives in chaos and darkness, he is frightened by the light. These subhuman creatures dwell in the cesspools, and swamps, preferring a hell on earth, to the light of the sun…. The subhuman hordes would stop at nothing in their bid to overthrow the world of light and knowledge, to bring an apocalypse to all human progress and achievement. Their only goal is to make a desert wasteland of any nation or race that shines with creativity, goodness and beauty.

Similarly, during the Jim Crow era many racist Whites imagined Black men to be predatory beasts that were hell-bent on rape and murder, and routinely described them as fiends and monsters. In Thomas Dixon’s novel The Clansman (on which the notoriously racist 1915 film The Birth of a Nation was adapted) Gus, a former slave who rapes a white woman, is described as a monstrous creature. He has “gleaming apelike” eyes and his “thin spindle-shanks supported an oblong, protruding stomach, resembling an elderly monkey’s, which seemed so heavy it swayed his back to carry it. The animal vivacity of his small eyes and the flexibility of his eyebrows, which he worked up and down rapidly with every change of countenance, expressed his eager desires.” When he approached his victim, his “thick lips were drawn upward in an ugly leer and his sinister bead eyes gleamed like a gorilla’s. A single fierce leap and the black claws clutched the air slowly as if sinking into the soft white throat.” More recently, the characterization of Latinx migrants not only as rapists and murderers, but also as blood-thirsty animals, is headed in the same disturbing direction.

We all know where these images lead. They lead to the living hell of Auschwitz, to the unimaginably cruel and gruesome spectacle of lynching, and now to the detention centers that deface the American landscape.

This isn’t cinematic horror or the play-horror of Halloween. This is real horror.