Pope Leo XIV published his first encyclical, Magnifica Humanitas, on May 25 (Pentecost Monday). The document runs to about 43,000 words and argues that the development of artificial intelligence (AI) risks undermining the meaning of human existence; it calls for safeguarding and defending human dignity in the face of AI.
Accusations of AI authorship
Shortly after publication, accusations surfaced claiming the encyclical had been written with the help of artificial intelligence, effectively charging Pope Leo XIV with hypocrisy. The Vatican never admitted to such use and sought to discredit the allegations.
Independent detectors and the tools behind the debate
Part of the controversy centered on analyses performed with AI-based detection tools. One widely known tool was developed by Pangram Labs; it gained attention because X users can tag posts to receive an analysis indicating whether a given text was likely generated by AI. Pangram Labs reportedly flagged multiple posts from official accounts linked to Pope Leo XIV as likely AI-generated.
Pangram Labs’ analysis of the full encyclical indicated that most of the document appears to be human-authored, but some paragraphs showed patterns consistent with AI-generated text.
Academic perspective
AI researcher Linch Zhang also analyzed the encyclical and concluded that there may indeed be passages generated by artificial intelligence. Zhang added that Vatican officials appeared to have used such analyses to reinforce the message of the text rather than to discredit Pope Leo XIV personally.
The Vatican’s commissioned check: Proudly Human
Dissatisfied with the partial AI-detection results, the Vatican commissioned its own verification through a company called Proudly Human. Proudly Human issues certificates intended to attest that a given text was written by a human and not produced by artificial intelligence.
To enable the check, the Vatican provided the company with a corpus of the pope’s speeches and other writings to serve as a control group. The encyclical and control texts were examined with several tools and then processed through Proudly Human’s proprietary averaging algorithm to assess stylistic nuances and grammatical patterns.
Based on that analysis, Proudly Human concluded that Magnifica Humanitas was entirely human-written.
Why the dispute matters
The episode highlights challenges in attributing authorship as AI tools and detectors become more widespread. The case pits concerns over public trust and technological limitations against institutional efforts to protect credibility. While independent detectors and some researchers flagged potential AI-like passages, the Vatican’s commissioned analysis returned a full human-authorship certification, leaving the matter subject to ongoing debate.
