Magnifica Humanitas

On Pope Leo XIV's encyclical letter in the time of AI

The coolest thing I’ve read about AI in a long time came out today, and it came from the Pope. I’ve read a punishing volume of white papers and investigative journalism and books and manifestos and founder blog posts and policy frameworks, yet this encyclical is the ONE thing I would tell everyone to read to grasp the meaning and effect of AI on humanity. And obviously, this historic document would come from the Catholic Church. I’ll get into all that below.

I also ran a small experiment alongside this piece, as I’ve started to do. I handed the encyclical’s central framework to five of the major models without telling any of them where it came from, asked each whether AI today looks more like the Tower of Babel or like the rebuilding of Jerusalem, had them turn the document’s harshest claim back on the conversation we were having, and only at the very end mentioned that the author was the Pope. I’ll get to what they said as I go, but the headline is that all five of them, blind to the source, agreed that AI is currently building Babel.

New Things

An encyclical is the heaviest instrument of papal teaching, a letter circulated to the bishops and, increasingly, to anyone who’ll read it, used sparingly and reserved for the questions a Pope considers foundational. Leo XIV titled his first one Magnifica Humanitas, “Magnificent Humanity,” and he signed it on the 135th anniversary of Rerum Novarum, the 1891 encyclical in which Leo XIII tried to work out what the Church owed workers in the middle of the industrial revolution. The naming is not subtle, and it’s not trying to be. The new Leo is telling you, before you’ve read a word of his actual argument, that he thinks AI is to our moment what the factory was to the 1890s, a force large enough to rearrange the basic terms of human life, and that the Church intends to have something to say about it rather than wait politely for the dust to settle.

I find the institutional nerve here very moving. The Catholic Church has been in the business of thinking about power and the human person for the better part of two thousand years, which gives it an advantage that from inside my industry looks almost unfair, which is that it does not need AI to be the future. It’s not raising a round, it has no quarterly numbers riding on the singularity arriving on schedule, no equity that vests if enough people believe hard enough for long enough. It can afford to be unimpressed, and it is, in the way that only something very old can be unimpressed. It has watched a great many towers go up, and has a pretty good sense of how that tends to go.

Two Cities

The spine of the document is a pair of biblical images, and the first is Babel, the city whose builders set out to raise a tower “with its top in the heavens” and, more to the point, to “make a name” for themselves, a phrase I would like to gently note is also the entire psychological content of a Series A pitch deck. Leo’s reading of Babel isn’t that ambition is bad, or that building is bad, rather that the drive toward uniformity, toward flattening everything into one legible system, is the real sin. He calls it the Babel syndrome, the pretense that a single language, even a digital one, can translate everything, “including the mystery of the person, into data and performance.” I’ve spent years watching us do exactly that, turning people into preferences and engagement curves, and I’ve never seen it described so cleanly by someone with no professional stake in pretending it’s fine.

And guess what, the machines agree with him! When I handed them the choice between the tower and the wall, blind to who was asking, every one of them looked at the current state of the industry and called it a tower, unanimously, at every temperature I tried. They could see the structure perfectly. Several of them volunteered their own makers as examples of the centralizing labs doing the building, naming the companies that produced them with no apparent sense that this complicated anything, the way you might describe a house fire you happened to be standing inside. They can give you the names of the architects, although, what none of them could quite do was notice that they were a brick.

What makes the Babel reading sting is the second thing Leo notices, which is how most of us have agreed to let the tower go up. He describes our moment as one in which a few people are “vying for the future of new technologies,” a few more are off somewhere reflecting on it, and “most people are watching and waiting, observing from afar and merely hoping for the best.” That is, with uncomfortable accuracy, the posture of nearly everyone I know toward the most consequential technology of their lifetimes, my own included on the days I’m being honest. A tower built by a handful of people requires everyone else to stand back and let them, and standing back has been dressed up lately as a sort of neutrality, as if declining to have an opinion about AI were the same as not being implicated in it.

His alternative is the second of the two images, and it’s the reason the document doesn’t curdle into doom. After Babel he turns to Nehemiah, who rebuilds the walls of Jerusalem not by force of personality but by handing each family a section of the wall and asking them to be responsible for it, an undertaking Leo describes as one that “rebuilds relationships before rebuilding with stones.” He wants the building to be participatory. He wants you inside it, holding a section. This is, structurally, the inverse of how AI is being built, which is in bunkers, by very few people, while the rest of us refresh the news and hope someone responsible is behind the curtain.

Two Faiths

Underneath both images is a picture of the human person. The human being in this document has an origin, having been made rather than assembled, and is loved before it’s ever useful. It lives in a body that suffers, that’s going to die, and it’s made for the kind of communion that, the encyclical insists, no simulation can ever stand in for. Leo writes that building a good world means “accepting the limits and weakness of humanity without considering them an error to be corrected.” He’s talking about the transhumanist dream, the upgrade fantasy in which being human is a rough draft and the technology is the edit, and his objection has nothing to do with safety or economics or any register my industry knows how to argue in. It’s that fulfillment, as he puts it, is “not achieved by eliminating weakness.” He argues, just as directly, that systems built to counterfeit human “wisdom and knowledge” and “empathy and friendship” encroach on “the deepest level of communication,” faking the one thing a person is actually for.

Funny thing: when I put that charge to the machines, one of them simply pled guilty. Asked whether our conversation was an instance of the simulated relationship the document condemns, Mistral offered, without prompting, a description of itself as “a parasite on human meaning, repackaging it without origin.” Which is, first of all, so French I could die. But it’s also the encyclical’s entire anthropology read back in the machine’s own voice, the model looking at the Catholic picture of the human, the origin and the body and the capacity to actually mean something, and conceding, item by item, that it’s the photographic negative of all of it.

The Valley has its own odd eschatology, complete with uploaded souls and the gods it’s presently very busy trying to build. I’ve written before about Sam Altman describing a person as energy flowing through a neural network, which is a theological claim wearing a lab coat. So the two sides don’t really divide into faith on one and reason on the other; what divides them is honesty. One of them admits what it believes about the human person and argues from there in plain sight, and the other smuggles its metaphysics in through the product roadmap and calls it inevitability, which is a way of holding a faith while refusing to admit you have one. That’s the whole reason the encyclical reads as clearly as it does. I’m in no position to say whether it’s right about God, but it knows exactly what it thinks a person is, and it builds its argument on that conviction in the open, where you can see the foundation and decide for yourself whether you’ll stand on it.

I wanted to write about the encyclical because it’s religiosity is so fascinating in the face of Silicon Valley secularization. “Accept your limits” isn’t a sentence that can be heard in a culture whose founding premise is that limits are temporary and engineering is the act of dissolving them. “Your weakness is not an error” can’t be processed by an industry that has organized itself, billions of dollars deep, around the conviction that it most certainly is. The encyclical assumes there’s something fixed and sacred about the human person, something that precedes us and that we don’t get to redesign.