I FIRST READ KURZWEIL’S 1999 book, The Age of Spiritual Machines, in 2006, a few years after I dropped out of Bible school and stopped believing in God. I was living alone in Chicago’s southern industrial sector and working nights as a cocktail waitress. I was not well. Beyond the people I worked with, I spoke to almost no one. I clocked out at three each morning, went to after-hours bars, and came home on the first train of the morning, my head pressed against the window so as to avoid the specter of my reflection appearing and disappearing in the blackened glass. When I was not working, or drinking, time slipped away from me. The hours before my shifts were a wash of benzo breakfasts and listless afternoons spent at the kitchen window, watching seagulls circle the landfill and men hustling dollys up and down the docks of an electrical plant.

LOSING FAITH IN GOD in the 21st century is an anachronistic experience. You end up contending with the kinds of things the West dealt with more than a hundred years ago: materialism, the end of history, the death of the soul. During the early years of my faithlessness, I read a lot of existentialist novels, filling their margins with empathetic exclamation points. “It seems to me sometimes that I do not really exist, but I merely imagine I exist,” muses the protagonist of André Gide’s The Counterfeiters. “The thing that I have the greatest difficulty in believing in, is my own reality.” When I think back on that period of my life, what I recall most viscerally is an unnamable sense of dread — an anxiety that would appear without warning and expressed itself most frequently on the landscape of my body. There were days I woke in a panic, certain that I’d lost some essential part of myself in the fume of a blackout, and would work my fingers across my nose, my lips, my eyebrows, and my ears until I assured myself that everything was intact. My body had become strange to me; it seemed insubstantial. I went out of my way to avoid subway grates because I believed I could slip through them. One morning, on the train home from work, I became convinced that my flesh was melting into the seat.

At the time, I would have insisted that my rituals of self-abuse — drinking, pills, the impulse to put my body in danger in ways I now know were deliberate — were merely efforts to escape; that I was contending, however clumsily, with the overwhelming despair at the absence of God. But at least one piece of that despair came from the knowledge that my body was no longer a sacred vessel; that it was not a temple of the holy spirit, formed in the image of God and intended to carry me into eternity; that my body was matter, and any harm I did to it was only aiding the unstoppable process of entropy for which it was destined. To confront this reality after believing otherwise is to experience perhaps the deepest sense of loss we are capable of as humans. It’s not just about coming to terms with the fact that you will die. It has something to do with suspecting there is no difference between your human flesh and the plastic seat of the train. It has to do with the inability to watch your reflection appear and vanish in a window without coming to believe you are identical with it.

Transhumanism offered a vision of redemption without the thorny problems of divine justice. It was an evolutionary approach to eschatology, one in which humanity took it upon itself to bring about the final glorification of the body and could not be blamed if the path to redemption was messy or inefficient. Within months of encountering Kurzweil, I became totally immersed in transhumanist philosophy. By this point, it was early December and the days had grown dark. The city was besieged by a series of early winter storms, and snow piled up on the windowsills, silencing the noise outside. I increasingly spent my afternoons at the public library, researching things like nanotechnology and brain-computer interfaces.

I’VE SINCE HAD TO DISTANCE MYSELF from prolonged meditation on these topics. People who once believed, I’ve been told, are prone to recidivism. Over the past decade, as transhumanism has become the premise of Hollywood blockbusters and a passable topic of small talk among people under 40, I’ve had to excuse myself from conversations, knowing that any mention of simulation theory or the noosphere can send me spiraling down the gullet of that techno-theological rabbit hole.

This is not to say that I have outgrown those elemental desires that drew me to transhumanism — just that they express themselves in more conventional ways. Over the intervening years, I have given up alcohol, drugs, sugar, and bread. On any given week, my Google search history is a compendium of cleanse recipes, HIIT workouts, and the glycemic index of various exotic fruits. I spend my evenings in the concrete and cavernous halls of a university athletic center, rowing across virtual rivers and cycling up virtual hills, guided by the voice of my virtual trainer, Jessica, who came with an app that I bought. It’s easy enough to justify these rituals of health optimization as more than mere vanity, especially when we’re so frequently told that physical health determines our mental and emotional well-being. But if I’m honest with myself, these pursuits have less to do with achieving a static state of well-being than with the thrill of possibility that lies at the root of all self-improvement: the delusion that you are climbing an endless ladder of upgrades and solutions. The fact that I am aware of this delusion has not weakened its power over me. Even as I understand the futility of the pursuit, I persist in an almost mystical belief that I can, through concerted effort, feel better each year than the last, as though the trajectory of my life led toward not the abyss but some pinnacle of total achievement and solution, at which point I will dissolve into pure energy. Still, maintaining this delusion requires a kind of willful vigilance that can be exhausting.

a friend of mine from Bible school, a fellow apostate, sent me an email with the title “robot evangelism.”

I suppose I’d been hoping that Benek would hand me some final hermeneutic, or even offer a portal back to the faith, one paved by the certitude of modern science.

There were old bodies and young bodies, men and women, their limbs tanned and lambent with perspiration.