Encyclical Magnifica humanitas (2026)

As of 1 October 2026. Information only, not legal advice – see the disclaimer.

Magnifica humanitas is the first encyclical of Pope Leo XIV. It was signed on the 135th anniversary of Leo XIII's encyclical Rerum novarum (1891) and places artificial intelligence in the tradition of the Church's social doctrine. The text has an introduction, five chapters and a conclusion (245 paragraphs). Chapter Three addresses AI, responsibility, transparency and governance; Chapter Four addresses truth, communication and disinformation, work and freedom; Chapter Five, “The culture of power and the civilization of love”, addresses war, weapons and artificial intelligence, cyberspace, the crisis of multilateralism, diplomacy and the United Nations. The entry records the passages relevant to peace and conflict in the cyber and information sphere; it does not summarise the theological content.

• No. 106 – calls for “robust legal frameworks, independent oversight, informed users and a political system that does not abdicate its responsibility” in governing AI.
• No. 110 – “Disarming AI”: freeing it from the mentality of “armed” competition, which “is not limited simply to the military context”; “merely regulating it is insufficient; it must be disarmed, welcoming and accessible”.
• No. 132 – “Disinformation did not begin with AI, yet today it finds a powerful amplifier in AI.”
• No. 183 – describes hybrid forms of conflict “such as cyberattacks, information manipulation, campaigns of influence and the automation of strategic decisions”, with AI as an accelerating factor that can “lower the threshold for the use of force”.
• No. 192 – “without prejudice to the right to self-defense in the strictest sense”, reaffirms that the “just war” theory “is now outdated” (with reference to Fratelli tutti, 258).
• No. 194 – refers to the Treaty on the Prohibition of Nuclear Weapons as “an important step” which “risks remaining largely symbolic since the major nuclear powers have not agreed to it”, and describes the belief that nuclear deterrence is indispensable for security as “erroneous”.
• No. 197 – citing the Holy See, states that the ease of deploying autonomous weapons systems makes war more “feasible” and less subject to human control; the development and use of AI in warfare “must be subject to the most rigorous ethical constraints”.
• No. 198 – “it is not permissible to entrust lethal or otherwise irreversible decisions to artificial systems. No algorithm can make war morally acceptable.”
• No. 199 – three criteria: personal responsibility (an identifiable and verifiable chain of responsibility), the moral timeframe for judgment, and the identification and protection of civilians.
• No. 200 – “non-negotiable requirements”: traceability of decision-making in all systems used in a war setting; the decision to use lethal force “must remain under effective, self-aware and responsible human control”; and “a shared framework — also at the international level — in order to curb the technological arms race and ensure robust protection for civilians and the infrastructures necessary for their survival”.
• Nos. 202–203 – the force of international law being “replaced by the claim that 'might makes right'”; tribunals for disputes between States and for war crimes “weakened or bypassed”; achievements of humanitarian law “being compromised”.
• No. 225 – “Cyberspace too has become a battleground”; uncertain attribution increases “the risk of disproportionate reaction, miscalculation and escalation”; diplomacy should negotiate “shared regulations on the use of digital technologies” to protect civilians.
• No. 226 – international organisations, “particularly the United Nations”, are “essential instruments”; their current weaknesses “reveal the need for profound reforms”.

The encyclical does not create legal obligations. It is relevant to the debate documented on this site as the position of the Holy See, which takes part in the CCW discussions on lethal autonomous weapons systems (laws). Its requirements of effective human control over lethal force and of an international framework correspond to positions in the debate on a treaty on autonomous weapons (laws_treaty); its passages on cyberspace and attribution touch on the UN framework of responsible State behaviour (ict_norms) and on the risk of escalation (nc3). The text refers to earlier documents of the Holy See, including the note Antiqua et nova of the Dicastery for the Doctrine of the Faith and the Dicastery for Culture and Education (published 28 January 2025) on the relationship between artificial intelligence and human intelligence.

• 2025-01-28: Publication of the note Antiqua et nova on the relationship between artificial intelligence and human intelligence (Dicastery for the Doctrine of the Faith; Dicastery for Culture and Education), which states that lethal autonomous weapon systems are a “cause for grave ethical concern” (no. 100); the encyclical cites it in no. 197 (Holy See).
• 2026-05-15: Encyclical signed (Holy See).
• 2026-05-25: Encyclical presented in the Synod Hall in the presence of the Pope; in his address the Pope said that “artificial intelligence now demands to be 'disarmed,' freed from logics that turn it into an instrument of domination, exclusion and death” and referred to “increasingly autonomous weapons systems practically beyond any human reach to govern them effectively” (Holy See).

• laws_treaty
• laws
• military_ai
• reaim
• nc3
• ict_norms
• charter
• icj_nuclear_weapons

• Holy See, Encyclical Letter Magnifica humanitas (15 May 2026), English text, accessed 2026-10-01
• Holy See Press Office, Presentation of Pope Leo XIV's Encyclical Letter "Magnifica Humanitas" (18 May 2026), accessed 2026-10-01
• Pope Leo XIV, address at the presentation of the encyclical (25 May 2026), accessed 2026-10-01
• Dicastery for the Doctrine of the Faith and Dicastery for Culture and Education, Antiqua et nova (28 January 2025), accessed 2026-10-01
• UNODA, CCW High Contracting Parties and signatories, accessed 2026-10-01

• 2026-10-01: Entry created.