Pope urges world to ‘slow down’ on AI in fervent plea

In his first major document, Pope Leo called on governments to slow the development of artificial intelligence systems, warning that they spread misinformation, prioritize conflict and risk leading the world onto a path of endless war.

Leo, who has adopted a tougher tone in recent months and drew the ire of US President Donald Trump after criticizing the Iran war, made a series of impassioned appeals to world leaders in the long text known as the circular.

The first US Pope called on policymakers to protect workers’ rights and protect children from technology so that ownership of AI data should not be left solely in private hands, and he called for competition between AI companies to cool.

“What is needed is a more active political participation that can slow things down while everything is speeding up,” Leo said in the text titled Magnifica Humanitas.

The pope called for “robust legal frameworks, independent oversight, informed users and a political system that does not abdicate its responsibility.”

Circulars are one of the highest forms of teaching, extending from a priest to the 1.4 billion members of the Church.

Monday’s eagerly anticipated text of nearly 43,000 words has been in the works almost since Leo was elected Pope just over a year ago.

The document, which takes artificial intelligence as its central theme, also condemned the number of wars shaking the world, lamented the weakening of multilateral institutions and warned that arms industry profits were the driving force behind conflicts.

“The past 60 years have been marked by conflicts of astonishing brutality, often affecting civilian populations on a massive scale,” Leo said in the English-language text.

“Humanity is shifting towards a culture of violent power, where peace no longer appears as a responsibility to be assumed but as a delicate interval between conflicts,” he said.

Leo also made one of the clearest statements ever by a Pope rejecting the just war theory that the Church has used to evaluate global conflicts since at least the fifth century.

The doctrine, which generally states that wars should only be fought in defense against aggression, has also been used by Trump administration officials, including Catholic Vice President J.D. Vance, to defend the Iran war.

“The ‘just war’ theory so often used to justify all kinds of war is no longer valid,” Leo wrote.

“The use of force, violence and weapons reflects relational poverty, which invariably leads to disastrous consequences for civilian populations.”

Leo also expressed concern that leaders might start a war to distract citizens from domestic problems.

“We cannot rule out the possibility that some leaders view armed conflict as an effective way to divert attention from domestic problems and as a cynical tool to manage difficulties,” he said.

The Pope said any use of AI in warfare “must be subject to the strictest ethical constraints” and said it was “impermissible” to give AI systems lethal decisions.

Leo, the 14th Pope to choose this name, cited centuries of papal teachings on social justice issues before touching on the ethics of artificial intelligence systems.

In particular, he referred to his predecessor, Leo XIII, who issued a famous encyclical in 1891 calling for better wages and conditions for workers during the Industrial Revolution.

Leo XIV condemned the “new forms of slavery” endured by people interested in artificial intelligence systems and factory workers who produce technological devices such as computers and smartphones that use artificial intelligence.

“In some parts of the world, children and adolescents work in dangerous conditions, crushing materials from which rare earth elements are extracted,” the pope wrote.

“The bodies of these people are injured, bruised and worn out, so that the flow of calculations can continue uninterrupted,” he said.

“This truth profoundly challenges the moral conscience of our age.”

The pope also offered a personal apology, acknowledging that the Catholic Church did not forcefully condemn transatlantic slavery until the 19th century.

“This creates a scar on Christian memory,” he wrote. “For this, I sincerely ask for forgiveness on behalf of the Church.”

Stating that he wanted to address Catholics and all people of good will in the opening of the letter, Leo said that society must face “critical questions” about how artificial intelligence develops and the general direction of global leadership.

Referring to the Biblical story of the Tower of Babel, where a tribe of people tried to build a tower high enough to reach Heaven out of pride and angered God, the Pope said the story showed the risk of any attempt “aiming to reach heaven without the grace of God.”