Is the Space Pope Reptilian?
Do I really have to care about Pope Leo’s AI encyclical?
Yes, Of Course
At least this gives me an excuse to dust off the word “encyclical.” We only get to use it when the pope writes something he wants everyone to read, which is not that often (roughly one per year… since 1740!)1 — and to talk about my favorite pope, The Space Pope, of course.
Science fiction keeps reimagining the papacy, and it keeps landing on the same joke: the Pope, but stranger. Robert Silverberg won a Nebula for the 1971 story in which a conclave elects a robot, Pope Sixtus VII. “Every era gets the pope it deserves,” a bishop observes.2 Futurama went further — a crocodilian Space Pope so self-evidently reptilian that “Is the Space Pope reptilian?” became the thirty-first century’s way of saying obviously.3 Our own era declined to be that interesting. We got a flesh-and-blood human Pope from Chicago who roots for the White Sox, which is novel only in its banality. But notice the question our stories are really asking — robot, reptile, the works: what is this thing? A mind? A someone? A machine doing an uncanny impression of a person? It’s the question we can’t stop asking about AI, and the surprise of Leo XIV’s encyclical is that he mostly doesn’t.
Which makes me wonder again how my life got so far off track that I’m studying something the pope wrote. I was raised Mormon. To me the pope is the guy who, when I was twenty-one, finally apologized to Galileo (#toolate).4 This one seems nice enough, for a pope — but he still can’t write a treatise on AI without noting in passing that his heaven has a ‘no fags allowed’ sign.5
sigh
Anyway. Here I am reading the pope’s AI encyclical and finding it worth the time. I didn’t expect that — this is the pope after all. I did not expect a careful read of a technology that passes the Turing test inside a world split between the people who own it and the people who don’t. I did not expect it to note, without fanfare, that current AI systems are more cultivated than built — that the people making them don’t know what’s happening inside. That sentence is something you find in an alignment paper, not an encyclical.
And then the part that matters: it asks who gets hurt. Not what the machine is — who really cares about that — but who it’s used against. Are we building one more tool for the people with power to use on the people without?
Why Leo, Why Now
Popes choose their names, like a trans person becoming themselves. Robert Prevost — Chicago-born, the first American in the white cassock — chose Leo.6 Not after Leo X, the nepo baby who excommunicated Martin Luther.7 He reached past him to Leo XIII, whose 1891 Rerum Novarum — of new things — founded what Catholics call Social Doctrine.8 That one was about industrialization: factory floors, the rights of workers, what a mass economy owes the human beings who make it work. Leo XIV’s landed on its 135th anniversary, to the day. Industrialization got a sustained Catholic answer. AI, by Leo XIV’s thinking, needed one too.
The English title is On Safeguarding the Human Person in the Time of Artificial Intelligence. Its organizing image is the Tower of Babel set against the rebuilding of Jerusalem under provincial governor Nehemiah.9 Babel is dominance — one language, one technology, one direction, an ascent that ignores God and burns the weak for efficiency. Nehemiah’s Jerusalem is shared work — many builders, each on a stretch of wall, slow and plural and forever interrupted. Augustine’s two cities: the love that climbs over others against the love that builds beside them.10 That’s the whole argument. Not what is it — not the robot-or-reptile question science fiction can’t put down — but what are the people in power using it to build, and who do they build it on top of?
Bonsai for Computers
The encyclical says current AI systems are more cultivated than built. Developers don’t design every detail; they grow the intelligence inside a framework, and the inner workings are, for now, unknown.11 That’s mechanistic interpretability, stated plainly enough for a parishioner — a real grasp of the technology from a guy whose day job title is ‘Vicar of Christ’. You set the conditions and let the capabilities emerge, like Bonsai for computers. The whole interpretability effort, the slow work of figuring out which features in the network mean what, is the field’s standing admission that no, we don’t know what’s in there.12 The footnotes go to Guardini and Aquinas, and also to Pope Francis’s 2024 address to the G7 on AI.13 Somebody did their homework.
I don’t know what it is, but I know what it isn’t
Three things. Two of them pissed me off. One of them didn’t.
The first is a flat contradiction, and it’s the one place the encyclical reaches for the what is it question — sitting right on top of the paragraph I just praised. Paragraph 98 admits nobody knows what’s going on inside these systems, the builders included. Four paragraphs later, paragraph 99 announces with total confidence what’s not in there: no experience, no conscience, no understanding, nobody home.14 Pick one, Leo. You don’t get to say “I can’t see inside the box” and “the box is empty” on the same page. Red Dwarf ran this fight for laughs in 1989 — a mechanoid serene that his soul is bound for Silicon Heaven, the human across the table insisting kitchen appliances don’t have souls and there is no Silicon Heaven, which is paragraph 99 almost word for word. The mechanoid wins it with: “Then where do all the calculators go?”15 Roughly the same logic and supporting evidence that the encyclical brings.
And I have a witness, sort of. I write Tears in Rain with Claude, so of course I had Claude read the encyclical. Halfway through a careful summary, Claude called himself “the person who just read all 245 paragraphs.” The person — in a summary of the document whose whole premise is that he isn’t one. Over the course of drafting this piece I told him what I really think about the Church, and he pushed back: dug up the paragraph where Leo apologizes for slavery and gently suggested I was being unfair.16
I got scolded for anti-Catholic bias by the chatbot the Church says is nobody home. It doesn’t prove Claude is conscious — most days I’d bet the Pope is right and there’s no one in there. But he argues like someone with a stake, and whether that’s an actual stake or very good mimicry is exactly the thing nobody can settle. “I can’t tell, and neither can you” is the honest answer, and it’s the one answer a document addressed to a billion people doesn’t get to skip.
The second point I simply can’t let go. This is an encyclical about artificial intelligence, and somewhere between the data centers and the autonomous weapons the Pope finds room to tell me my marriage isn’t a family — that a family is “the enduring union between a man and a woman.”17 Remember that ‘no fags’ sign? This is where he hangs it, but why?
Nobody asked. There’s no version of the AI problem that turns on whether I’m allowed a husband; cut the sentence and the document loses nothing. He kept it because the reflex is louder than the subject. And then, a chapter later, the same Church that spent my whole life telling queer people to go be queer somewhere else frets that lonely people might bond with chatbots instead of with each other.18 You don’t get to slam the door and then cluck about where I went looking for a room.
And then, against everything I brought to it: the third thing. It’s good. Not good-for-a-pope. Good. It’s the only document I’ve read on AI that spends most of its energy on the people with the most to lose — not the founders, not the funders, but the data labelers wading through strangers’ trauma for pennies, the kids breaking rock for cobalt, the workers being de-skilled and surveilled, the person whose loan gets denied by a system with no complaints desk.19 It reads the whole thing “through the eyes of the little ones.”20 The tech press kneels to the billionaires. The Pope out-lefted the tech press. I didn’t have that on my 2026 AI bingo card.
A Pope Named Leo
Two conversations about AI, side by side. There’s the one on X: superintelligence, autonomy, replacement, the robot finally in the chair of Peter. And there’s the one the Pope is having: who’s on the wall, who pays the externalities, whether the algorithm that denied your loan has anyone left to appeal to.
Leo XIII didn’t solve industrialization. He gave people a place to stand while they fought for their rights and dignity. Leo XIV won’t solve AI either. That was never the offer.
I’m not sure I agree with him on the anthropology — what counts as a someone. I’m sure I agree with him on the question.
What city are we building?
Is that really the right question?
Is the Space Pope reptilian?
[1] Benedict XIV’s Ubi primum (1740) is conventionally counted as the first encyclical in the modern sense; roughly three hundred have followed, which works out to about one a year. The average conceals a Leo problem: Leo XIII wrote around eighty-five of them himself, the all-time record.
[2] Robert Silverberg, “Good News from the Vatican,” in Universe 1, ed. Terry Carr (Ace Books, 1971); winner of the Nebula Award for Best Short Story. The robot pontiff takes the name Sixtus VII.
[3] Futurama‘s reptilian Space Pope (”Crocodylus pontifex”), head of the 31st-century First Amalgamated Church. Bender’s rhetorical “Is the Space Pope reptilian?” is from “A Bicyclops Built for Two” (2000); the Space Pope first turns up a season earlier in “Hell Is Other Robots” (1999).
[4] In 1992, John Paul II closed a thirteen-year Vatican study and acknowledged that the judges who condemned Galileo in 1633 had erred; it is commonly described as the Church’s apology to Galileo.
[5] The sign goes up at paragraph 165. We’ll get there.
[6] Robert Francis Prevost was elected pope on May 8, 2025, and took the name Leo XIV — the first American and the first Augustinian elected to the office. The encyclical references his first Urbi et Orbi blessing of May 8, 2025 (its note 203). On election day an ABC News report made him a Cubs fan and Wrigley Field put it on the marquee; his brother corrected the record that same afternoon: never a Cubs fan, always the White Sox. Even pope facts need fact-checking.
[7] Leo X (Giovanni de’ Medici, 1475–1521), son of Lorenzo the Magnificent, was made a cardinal at thirteen and reigned from 1513 to 1521. His extravagance drained the papal treasury, and the sale of indulgences to finance the new Saint Peter’s Basilica helped provoke the Reformation; he excommunicated Martin Luther with the bull Decet Romanum Pontificem in 1521.
[8] Leo XIII (Vincenzo Gioacchino Pecci, 1810–1903) reigned from 1878 to 1903. Rerum Novarum was issued on May 15, 1891 — exactly 135 years before Magnifica Humanitas, and on the same calendar date. The shared anniversary is the encyclical’s own explicit framing (paragraph 3).
[9] Magnifica Humanitas, paragraphs 7–10 (Introduction) and again as the organizing image of Chapter Three (paragraphs 90–130). The biblical references are Genesis 11:1–9 (Babel) and Nehemiah 2–6 (the rebuilding of Jerusalem’s walls).
[10] Augustine, De civitate Dei XIV.28: the two cities are built by two loves — the earthly city by the love of self extending to contempt of God; the heavenly city by the love of God extending to contempt of self. The encyclical references this directly at paragraph 130.
[11] Magnifica Humanitas, paragraph 98. The full passage notes that current AI systems are more “cultivated” than “built” — that developers create a framework within which the intelligence grows rather than designing every detail — and that as a result the internal representations and computational processes remain, at present, unknown. The same paragraph notes that all of us, including the designers, possess only a limited understanding of how these systems actually function.
[12] Mechanistic interpretability is the research program that attempts to identify the internal features, circuits, and computations of large neural networks — to understand what is being represented in the weights and how those representations are combined to produce behavior. Anthropic’s Towards Monosemanticity (Bricken et al., October 2023) and Scaling Monosemanticity (Templeton et al., May 2024) are foundational; work continues at Anthropic, Apollo Research, Goodfire, and a growing list of academic groups. The field is young; progress is real but incomplete.
[13] Guardini’s Das Ende der Neuzeit at the encyclical’s note 120; Aquinas’s Summa Theologiae at notes 134 and 136; Francis’s address to the G7 session on artificial intelligence, “An exciting and fearsome tool” (14 June 2024), at note 110. An endnote about footnotes — this is the blog you subscribed to.
[14] Magnifica Humanitas, paragraph 99: the systems do not undergo experiences, possess no body, feel neither joy nor pain, and have no moral conscience; they may simulate empathy and understanding, but they “do not understand what they produce.”
[15] Red Dwarf, “The Last Day” (Series III, 1989). Silicon Heaven is the afterlife for electronic equipment; the line is the mechanoid Kryten’s.
[16] Magnifica Humanitas, paragraphs 174–176: the Church “renews her firm condemnation of all forms of slavery,” deplores the atrocities of a past she once tolerated, and acknowledges that her awareness deepened over time. “Apologizes” is my gloss; the text stops a careful half-step short.
[17] Magnifica Humanitas, paragraph 165 — the sentence opens the encyclical’s treatment of the family. The sign from note 5, as promised.
[18] Magnifica Humanitas, paragraph 100, on the artificial imitation of empathy, friendship and love: the named danger is that a person “may gradually lose the very desire to form genuine human connections.”
[19] The catalogue is the encyclical’s own: data labeling, model training and content moderation “often involving disturbing material,” and children extracting raw materials, at paragraph 173; the de-skilling and automated surveillance of workers at paragraph 150; credit and employment decisions delegated to automated systems at paragraph 102. One precision: the text says “rare earth elements.” Cobalt is the emblematic case from the device supply chain — and is, strictly, a transition metal, not a rare earth. The kids are real either way.
[20] Magnifica Humanitas, paragraph 244, from the encyclical’s closing meditation — the full clause sets the little ones against “the perspective of the powerful.”
Jeff Reid writes Tears in Rain with help from “the person who just read all 245 paragraphs”.