The military testing area at White Sands, N.M., is a forlorn and silent place. It was here that the boundaries of technological possibility, the boundaries of fear, were redrawn by men of science in the last days of World War II; it was here, in July 1945, that the first atomic bomb was detonated, the prototype of the Fat Man plutonium device that was delivered three weeks later from the heavens to the mortals of Nagasaki. Here at White Sands, science made its nearest approach to divine likeness, divine knowledge. Here, with these experiments in celestial violence, humanity came closest to transcending itself, fulfilling itself.

Just past the security checkpoint at the entrance to the facility, there was a kind of open-air munitions exhibit that featured a squat replica of the Fat Man, along with dozens of other decommissioned rockets and bombs. In the undulating heat of the desert, these slender tilted obelisks loomed like the inscrutable monuments of an ancient thanatopia, a henge of metal phalluses thrusting skyward in ecstatic communion with the cosmic powers. Istvan removed from his backpack a banner he had printed for the occasion and, positioning himself in front of one of the larger rockets, instructed Horn to take a series of photographs of him bearing the rolled-out message: TRANSHUMANIST PARTY PREVENTS EXISTENTIAL RISK. The intention of the protest, if you could really call it that, was to create a series of images and short videos to be uploaded to Istvan’s various social-media accounts and shared among his many thousands of followers. Leaning self-consciously against the Fat Man replica, I scribbled in my notepad. Horn took out his phone and filmed a six-second Vine video of Istvan saying: “Stop nuclear war! It’s a devastating existential risk!” Then he filmed Istvan giving another brief speech on the central theme of his campaign: the need to divert government spending away from war and into research on life extension.

Later that evening, we pulled off the Interstate and checked into a motel. As I stood in the doorway, waiting for Istvan and Horn to get their stuff from the Wanderlodge, I browsed through a stand of leaflets by the entrance. Most of these advertised sites of general touristic interest — for instance, PistachioLand, “home of the world’s largest pistachio” — but there was also a small assortment of Christian pamphlets, and of these I selected one that was simply titled “Eternity.” It was a prospectus of the apocalypse, published by an outfit called the Gospel Tract and Bible Society. Standing in the empty lobby of the motel, I read of God’s decree that all things shall cease to exist — that “the heavens shall pass away with a great noise, and the elements shall melt with fervent heat, the earth also and the works that are therein shall be burned up” — and I thought again of the unearthly monument I had walked around that day, the ceremonial circle with its ranged machineries of death.

Reading on, I learned how I, or my soul, might survive the death of my body and all other worldly things by surrendering myself to the Lord. I remembered asking Horn, earlier that day, about how his religious upbringing might have informed his belief that he would live forever through science. He said there was no longer any need for gods.

“Science is the new God,” he said. “Science is the new hope.”

Horn, with his Calvinist background, seemed to me now a walking illustration of the way in which scientific progress had displaced divine providence as our culture’s locus of faith. He embodied, in fact, the religious dimension of transhumanism: a movement that, in its grand mythos of the coming Singularity, maintains a Christian distaste for the flesh and its frailties. Its delirious eschatology foretells a final unity with the technological divine, through which the elect will make the transition from time into eternity.

Istvan, by contrast, had come to transhumanism from a more secular, hedonic background. In his 20s, having graduated from Columbia University with a degree in philosophy and religion, he fixed up an old yacht and set out to circumnavigate the globe. He funded his trip partly by making short documentaries for the National Geographic Channel about the remote places he was visiting. Somewhere along the way, he invented an extreme sport called volcano boarding (basically snowboarding, except you do it on the slopes of an active volcano). While reporting on the large number of buried land mines still remaining in Vietnam’s former DMZ, Istvan himself came very close to stepping on one; his guide tackled him from behind as he was walking and brought him to the ground just inches from where an unexploded mine was jutting from the earth.