In a 42,300-word document signed on the 135th anniversary of the Church's landmark labor encyclical, Pope Leo XIV declared that technology is never neutral and called on governments and corporations alike to disarm AI from logics of domination, exclusion, and war — with an Anthropic co-founder seated in the front row.
When Pope Leo XIV stepped to the podium at the Vatican on May 25, 2026, he did something no pope before him had ever done: he delivered, in person, the first papal encyclical dedicated entirely to artificial intelligence. Standing alongside him — in a row typically reserved for cardinals and theologians — was Christopher Olah, 33-year-old co-founder of Anthropic, the AI safety company behind the Claude family of models. The image alone made headlines worldwide. The document they had gathered to discuss may prove more consequential still.
Magnifica Humanitas: On Safeguarding the Human Person in the Time of Artificial Intelligence runs to 42,300 words across five chapters. Pope Leo XIV signed it on May 15, 2026 — a date chosen deliberately: the 135th anniversary of Rerum Novarum, the 1891 encyclical by Leo XIII that first staked the Church's claim on the ethics of industrial labor. The parallel is unmistakable. Just as Rerum Novarum responded to the exploitation unleashed by the Industrial Revolution, Magnifica Humanitas plants the Church squarely in the center of the argument over who controls, and who benefits from, the AI revolution now reshaping nearly every domain of human life.
What the Document Says
The encyclical opens with a statement that sets the tone for everything that follows: "Technology is never neutral." In Leo's framing, every algorithmic system encodes the values of those who built it and the incentives of those who deploy it — and both sets of actors must be held accountable.
The five chapters work through the terrain systematically. The first grounds the analysis in Catholic social teaching, drawing a line from Rerum Novarum through Centesimus Annus and Laudato Si' to the present. The second and third turn to labor and human dignity, arguing that automation that displaces workers without redistributing its gains is a moral failure, not merely an economic one. The fourth takes up truth, warning that algorithmic amplification of misinformation represents a structural threat to democratic deliberation. The fifth — the most immediately topical — addresses AI in warfare, data privacy, and algorithmic bias.
On autonomous weapons, Leo's language is among the sharpest in any official document from any institution. He identifies "increasingly autonomous weapons systems practically beyond any human reach to govern them effectively" as a categorical threat, and sets three requirements: traceability of decisions, meaningful human control over lethal action, and binding international agreements capable of slowing the technological arms race in lethality. In a passage that drew immediate commentary, he declared the traditional just war framework effectively obsolete: "The 'just war' theory which has all too often been used to justify any kind of war, is now outdated."
On algorithmic bias, the encyclical warns explicitly of "algorithms that can block access to healthcare, employment, and security on the basis of data tainted by prejudice and injustice." On data privacy, it condemns the "concentration of power in the digital world" that flows from the asymmetric harvesting of personal information at scale. Together, those passages amount to a comprehensive indictment of how AI has been deployed in consequential decisions affecting billions of people — and a demand for accountability structures that do not yet exist in most jurisdictions.
An Unlikely Partnership
The choice to present the encyclical personally — most popes delegate that task to cardinals — underscored how central the document is to Leo's papacy. The choice of co-presenter was equally deliberate.
Olah, who has spent most of his career doing foundational research on neural network interpretability, spoke to a packed Vatican auditorium about why the Church's voice matters to people inside the technology industry. "This is the beginning of a long collaboration between those of us who are building this and those who can see what we, from inside, cannot," he said. He echoed the encyclical's concern about concentration, noting that AI development is "concentrated in a handful of wealthy nations" and urging that "the gains of AI are shared globally."
The presence of an Anthropic co-founder alongside the pope did not go unnoticed in Washington. The Washington Post, in a detailed analysis published the same day, described Anthropic as having effectively "aligned with the Vatican over the White House" — a reference to the current administration's largely deregulatory posture toward AI. The framing may oversimplify a complicated relationship, but it captures something real: Anthropic has consistently positioned itself as an AI safety company willing to accept constraints that competitors resist, and the Vatican event reinforced that brand identity in front of a global audience.
Historical Weight, Immediate Stakes
The invocation of Rerum Novarum is not rhetorical decoration. That 1891 document helped catalyze the labor movement, gave intellectual legitimacy to workers' rights, and influenced social policy across dozens of countries for generations. Scholars of Catholic social teaching argue that encyclicals operate on a long timeline — they establish moral frameworks that shape legislation and culture over decades, not news cycles.
Sally Scholz, writing in the National Catholic Reporter, described Magnifica Humanitas as a document that "beautifully synthesizes the tradition," praising its focus on solidarity as a counterweight to the individualist logic that has dominated tech industry discourse. The Wall Street Journal called it "a text that is poised to define Leo's papacy" — a striking assessment for a document that most of its readers will encounter through summaries rather than the full 42,300 words.
The document arrives at a moment when international AI governance is fragmented and contested. The EU AI Act has been in force but faces pressure from member states seeking competitive carve-outs. The United States has retreated from the Biden-era executive order framework. China's AI regulation prioritizes content control over safety. Into that vacuum, Magnifica Humanitas advances a coherent moral framework — one that will now circulate through 1.4 billion Catholics, thousands of dioceses, and the vast network of Catholic universities, hospitals, and social service organizations worldwide.
None of that translates automatically into law. But it creates something arguably more durable: a shared vocabulary for the argument. When a bishop in Lagos, a hospital ethicist in Manila, or a labor negotiator in São Paulo invokes the principles of Magnifica Humanitas in a dispute over AI deployment, they will be drawing on the same document. That is how Catholic social teaching has always worked — and it is why this encyclical, whatever its immediate policy impact, represents a significant moment in the long arc of AI governance.
What to Watch
The encyclical does not name specific companies or governments. That restraint is deliberate — Catholic social teaching typically operates at the level of principle, leaving application to local actors. But the principles established in Magnifica Humanitas are specific enough to generate concrete policy demands: mandatory human oversight of lethal autonomous systems, algorithmic transparency requirements, data privacy protections framed as human rights, and redistribution mechanisms for the economic gains of automation.
Whether those demands find legislative expression will depend on actors far from the Vatican. What Leo XIV has done is ensure they cannot be dismissed as purely technical questions, or treated as matters for engineers and economists alone. The Church has entered the room — and it brought 135 years of social teaching with it.
"This is the beginning of a long collaboration between those of us who are building this and those who can see what we, from inside, cannot."— Christopher Olah, Co-founder, Anthropic