I place many of my articles on academia.edu so anyone can read them. One of them, “The Growing Evidence for ‘Demonic Possession’: What Should Psychiatry’s Response Be?” stands out. It has had more views (over 12,000) in four years than all the other forty put together. Clearly there is an immense interest in the subject, but do “demons” really exist, and do they target their victims?

In the few hundred words I’m allowed here, I’ll describe some of the physical displays that the demonically possessed are capable of. All are vouched for by credible witnesses. All suggest something decidedly superhuman. Conventional materialist theories can’t account for them.

Before looking at these feats, let me clarify what I mean and don’t mean by demonic spirits. I don’t mean anything like devils with tails and pitchforks who fell from heaven with Lucifer and have been cursed by God to an eternal life in some cosmic ghetto. I mean intelligent beings, insensible to us, with a will of their own, who oppress us and, in advanced cases, possess our bodies outright. Most of them, and possibly all of them, once lived on earth.

We should not confuse them with the far more numerous beings we now call earthbound spirits, and whom Buddhists call “hungry ghosts” and Orthodox Jews “dybbuks.” These are beings, all with a history of life on earth, who flee conditions on the Other Side and navigate earth without the advantage of a physical body. They gravitate toward people with the same weaknesses they had before their own death. Like parasites, the spirits of men and women who die as drunks, to take but one example, attach themselves to living alcoholics and “drink through them,” thus making it doubly difficult for drinkers to reform themselves.

Earthbound spirits do serious harm, but they are seldom motivated by hatred for the persons whose lives they help ruin. They just want relief from their own pain. But others, the subject of this essay, are clearly malevolent. These delight in destroying lives. They are the serial killers of the afterworld. Often they target specific individuals. They especially delight in bringing about a suicide. Many schizophrenics who hear voices in their heads urging them to destroy themselves will tell you, if you permit them to speak, that these voices are alien. They don’t come from within, as most psychiatrists think. These “voices” are the ones we should reserve the word “demonic” for.

So what is the evidence for these dark entities? There are many indicators. Francis MacNutt, a leading Catholic figure in the spiritual healing ministry, has seen them all: “A woman may start to speak in a husky voice like a man, or a mild-mannered person may begin speaking in a snide, insulting tone of voice.” Often the voice uses the plural we and on rare occasions speaks a foreign language unknown to the victim. MacNutt continues:

Perhaps the most common external indication of demonization comes when the person’s facial expression changes. It is as if you are no longer looking at the same person you started talking to. The old saying “The eyes are the windows of the soul” becomes especially meaningful. It is as if the evil spirit is peering out at you. The eyes become filled with hate, mockery, pride or whatever the nature of that particular spirit is. Now that the evil spirit has surfaced, you are no longer directly in touch with the person you have been praying for.

This kind of evidence leaves no doubt in experienced exorcists (or healers) that they are dealing with an alien spirit. Skeptics, of course, are not convinced. They are likely to scoff at all talk of spirits, especially demons. They require evidence that leaves little doubt. There is evidence aplenty. Here are four examples.

A recent case in Gary, Indiana, featured a boy who “walked backward up a wall and onto the ceiling” of a hospital room when his grandmother took his hand and started to pray for him. A horrified registered nurse who was in the room at the time told the Indianapolis Star, “There’s was no way he could’ve done that.”

An earlier case from China was witnessed by a roomful of persons, including two Daoist monks, one of whom had been called in to exorcize the demon. The other monk recorded what everyone saw: “With unutterable horror, we saw that [the man’s body] began to swell visibly. On and on the dreadful process continued until he became a grotesque balloon of a man.” Then, as the exorcist concentrated and commanded the demons to leave the victim, “streams of malodorous excreta and effluvia flowed on to the ground in incredible profusion.” This process, accompanied by an appalling stench, continued for an hour until the man finally resumed normal size.

The anthropologist Felicitas Goodman did field work on a case of possession in a Yucatan village of Mayan peasants in 1985. According to Goodman’s report,

She tore unripe, bitter bananas from the trees and ate them skins and all, and pulled hot chili peppers from the bushes and stuffed them whole into her mouth. She had enormous strength; she would uproot banana trees nine feet tall or more, or pick up large chunks of limestone, the building material of the area, and set them into the middle of the street.

But the true horror of possession is the suffering and degradation of its victims. In a famous 1975-76 German case, a pious young Catholic, Anneliese Michel, “seethed with heat.” To relieve herself, Goodman reports,

She rolled in the coal dust in the basement, filled an old iron kettle with icy water and jumped into that, or stuck her head into the commode in the bathroom. She tore her clothes off and ran around in the house naked…. She stuffed flies and spiders into her mouth and chewed on coal, or on her urine soaked panties.

What do we do with all this evidence of apparent spirit oppression? In particular, can it be squared with the materialist worldview of Western psychiatry? Is “demonic possession” always to be placed within quotation marks, or can we leave them off? Are “spirits” the hallucinations of a sick brain, or do they have an independent existence? I think every reader must grant, however grudgingly, that on the surface the accounts above—out of thousands of similar reports reaching us from all over the world—point to a dualist metaphysics: We are one kind of being, and spirits are another. We are visible, and they are not. We are subject to the laws of physics, and they are not. We have physical bodies, and they do not. Yet they are as conscious as we are, as individual as we are. And many of them claim to have lived on earth before.

How medical doctors and social scientists should adjust their view of possession will be the subject of a follow-up essay.