When I last visited New Orleans, the ­Robert E. Lee Monument was being used as an altar. Two voodoo priestesses, turbans atop their heads, scattered gunpowder and grave dirt on the granite plinth. With splendid indifference to those who had erected the memorial, they summoned their gods through an offering of rum and cheap cigars.

It was a sign of the times. Worship of strange spirits is on the rise in America, often in ways we do not acknowledge. Tarot readers, ghost hunters, UFO abductees, and shamanic healers may not seem to have much in common with the noble pagans of old. But in a society shaped by comics, sci-fi, and multi-culti kitsch, inchoate polytheism manifests itself as paranormal belief.

According to Pew Research, 65 percent of Americans believe in the paranormal, and their number is increasing. Christianity never denied the reality of what St. Paul calls “principalities and powers,” but its hatred of idols and demons restrained interest in the occult. Now that aversion is declining along with the Christian churches. Paranormal belief and experience is more common among the young than among the old, among the unchurched than among the religious. Before his death in 2016, the Vatican exorcist Fr. Gabriel Amorth warned that witchcraft and devil worship were rapidly spreading.

I want to understand what’s going on at the borders of belief, so I go to Brooklyn. As I stand outside the unassuming storefront in Greenpoint and have a smoke, I can see the sun setting over Manhattan. It is the night of the summer solstice, and the worshippers I am about to join are marking the change of light with a shamanic healing conducted in accordance with “Inca values.” (I have a vague notion that “Inca values,” like “Progressive values,” involve child sacrifice, quinoa, and needless war.)

A woman named Veronica tells me where to put my shoes, then leads me into a high-ceilinged room. Hemp mats are arranged around a low stone altar. It’s a whiter crowd than the one at the botanica where I inquired earlier today about Santería. (The santera referred me to her English-speaking daughter, who turned this gringo away.) The woman on the next mat says hello. I ask how she started coming here.

“This is only my second time. I found these people at the Heart and Mind Festival at St. Paul and St. Andrew Methodist on the Upper West Side.”

“Do you go there?”

“Oh, no. I like their values, but I prefer something more traditional. Like this.”

A rainbow flag is pinned to her bag.

Veronica is joined by Mackenzie, who helps her deal shamanic oracle cards. I get Study and Courage. Matteo, the shaman, strums a guitar as Veronica welcomes us. Her cadence takes me back to Solid Rock, the Evangelical youth group I attended before becoming a Catholic.

“I just want to welcome everyone. We’re so grateful you have joined to receive the sun’s power. Our maestro is at Stonehenge and is sending the force of that place here to us. We just encourage everyone here to pray in their own way. We welcome all spirits. Now, there will be tobacco in today’s ritual, which we of course use only for prayer. Everything used today is free of additives.”

Candles and idols deck the altar. A plaster wolf, the model for a thousand screen-printed T-shirts, howls beside a soaring pewter eagle. A plush little pony in Lisa-Frank purple and pink is stabled beside Ganesha. Mackenzie directs us to rise and face east. So they worship ad orientem, too? Maybe this won’t be so bad.

Palms are lifted, faces expectant. “Welcome the golden eagle, the new day, who brings life.”

We pivot to the right, and my back is to the group. “We turn to the jaguar of the south, to receive its fierceness.”

Why did I come here? “We turn to the west, to the raven’s tidings.”

I am sure they can see my discomfort. “We turn to the wolf of the north, with its power.”

We raise our hands toward the ceiling, where plants and speakers hang. “We reach to the sky.”

We fall down and press our faces to the floor. “We welcome the earth.”

We stand and face versus populum. “With acceptance and self-compassion, we welcome ourselves.”

As gongs ring, we lie on our backs. The women begin an unholy asperges, spritzing the air with scented water. It is dark now. Spirit crystals are placed in my hands, but their light flees. The air is warm and close. I remove my suit jacket.

The women go around the room crouching over the worshippers. Hands sweet with incense run lightly over my forehead. Veronica removes my glasses.

“Relax. Open yourself up to the earth that you feel below, to the warmth of the air. Let go of your tension. Breathe.”

If my Evangelical upbringing had not imparted to me a primal horror of witches, I would laugh. As it is, I find I am no longer a reporter, but a terrified boy. She speaks strange words, and I try to bat them away. St. Michael the Archangel, defend us in battle. Be our defense against the wickedness and snares of the Devil . . . She brushes a damp broom over my temples, and I sink between reeds. She blows smoke at my forehead, and I choke with dust. Snakes swallow rats as my muscles spasm and knot. I need to loosen my tie.

She puts one hand on my diaphragm and one on my chest to slow my breathing, but they do not calm me. A didgeridoo plays, and unearthly groans come from the ceiling. Her fingers are on the nape of my neck, and I no longer feel the ground so firmly beneath me. Smoke hangs in the air around us—and then she is gone. I search for my glasses and jacket as the darkness lifts.

“Leave here in softness and gentleness. Go out more accepting of others and yourselves.” We all hug. “And remember that we have a variety of programs, both here and at our vegetarian restaurant.”

Everyone else seems lighter and happier, but I feel uneasy. Back in Manhattan, I find an open confessional. After my act of contrition, the priest laughs. “That’s the best thing I’ve heard all day.” Wanting to return the compliment, I look at his feet, which are sticking out from behind the partition.

“I like your Duck Dynasty Crocs.”

What I saw in Brooklyn is happening all across the West. Christianity’s decline is leading not to austere secularism, but to a wild flowering of shamanic healers, spirit crystals, and transcendental maharishis. No one better exemplifies the spiritual trajectory of our time than Arthur Conan Doyle, an advocate of scientific rigor who started life as a devout Catholic and ended it as the world’s most prominent spiritualist.

While studying with the Jesuits at Stonyhurst, Doyle made his first communion. He wrote to his mother: “Oh mama, I cannot express the joy that I felt on the happy day to receive my creator into my breast. I shall never though I live a hundred years, I shall never forget that day.” He was enrolled in the sodality of the Blessed Virgin Mary as Arthurus Doyle, servus perpetuus BVM.

His promises were soon forgotten. In adulthood, Doyle championed broad-minded inquiry and rejected the Catholic faith. “I regard hard-and-fast dogma of every kind as an unjustifiable and essentially irreligious thing,” he wrote. He admired Oliver Wendell Holmes, whose skeptical, scientific outlook would be immortally embodied in Sherlock Holmes of Baker Street.

Rigorous skepticism may work for storybook characters, but it cannot satisfy man. When spiritualist mediums brought automatic writing and table-rapping into Victorian parlors, Doyle was taken in. He became the most outspoken defender of spiritualism, accusing Harry Houdini of being a pawn of Rome when the magician exposed Doyle’s heroes as frauds. Like the people I joined in Brooklyn, Doyle wanted a nonjudgmental faith that welcomed all spirits. But in rejecting dogma, he opened himself to impostors, not excluding the greatest impostor of all.

We may be tempted simply to have an urbane laugh at the follies of the superstitious, but that would be a mistake. They see something the great and good cannot: We live in a world full of spirits. Agnostic indifference to this fact may be possible for a time, but very few men are capable of sustained and thoroughgoing unbelief. This is why no superstition is more ridiculous than the pretense of secularism, and anyone who thinks Christianity will give way to atheism is a far greater fool than the most credulous ghost hunter.

This winter, I hiked across the lava fields on the south slope of Kilauea. Shortly after we began, the guide bent down over the rock. In hopes that the volcanic goddess Pele would forgive us our trespassing, she made an offering of cocoa beans (organic—she grows them herself and sells them at the farmer’s market), laceleaf, and M&Ms, along with a libation of IPA. Her brand of bourgie superstition has a bright future in post-Christian America.

Of course, other options remain to us. After college, I moved into the attic of an old house where a ghost would sometimes appear in the window, an empty silhouette against the sky. I bore the spirit no ill will, but when I found a marble bust of St. Pius X that the Catholic chaplaincy had tossed out as rubbish, I carried it up to my room. From then on, I no longer saw the shadow of a ghost, but the solid outline of Giuseppe Sarto, servant of God.

Matthew Schmitz is literary editor of First Things and a Robert Novak Journalism Fellow.

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