Pope Leo has denounced the 'culture of power' driving the rapid rise of artificial intelligence, warning that the technology must be subject to the most rigorous ethical constraints as it infiltrates work, war and everyday life. In his encyclical Magnifica Humanitas, the first major text on safeguarding humanity of his papacy, he also apologised for the Catholic church's long delay in condemning slavery, describing it as 'a wound in Christian memory'.
The pope, who was born in Chicago and is the first US-born pontiff, presented the document himself at the Vatican on Monday. Among those in attendance was Christopher Olah, co-founder of the US-based AI firm Anthropic, which is embroiled in a lawsuit with the Trump administration over AI ethics. The encyclical, one of the highest forms of papal teaching, outlines Leo's priorities and highlights major societal issues.
In the document, Leo referred to 'a troubling revival of war as an instrument of international politics' and said AI was helping to facilitate the 'normalisation of war'. He urged the 'disarming' of AI, stating that some autonomous weapons systems are 'practically beyond any human reach' to control. 'Disarming AI means freeing it from the mentality of armed competition,' he wrote, adding that the technology should be 'human-friendly' and accessible to all.
The pope also warned that power over digital systems, infrastructure and data 'does not rest with states but with major economic and technological actors', and that when concentrated 'in the hands of the few' it tends to 'become opaque and evade public oversight, increasing the risk of distorted forms of development'. Olah echoed these concerns, saying AI development cannot be left solely to technology companies and urging greater oversight from religious leaders, governments and civil society.
On slavery, Leo wrote: 'It is impossible not to feel deep sorrow when contemplating the immense suffering and humiliation endured by so many... For this, in the name of the church, I sincerely ask for pardon.' His family history includes both enslaved people and enslavers. The Vatican has been seriously engaged on AI for several years, including regular consultations with tech leaders.
