Anthroc co-founder Chris Olah was in the audience when Leo published his first letter on Catholic doctrine.
WASHINGTON — In the halls of the Vatican’s 400-year-old St. Peter’s Basilica, the focus Monday was on a technology that is still in its infancy.
Pope Leo XIV proposed more than 42,000-word letter In his first encyclical as pope he talked about artificial intelligence.
The letter is subtitled “On protecting humanity in the age of artificial intelligence.” Its title is the Latin “Magnifica humanitus” – Great Humanity.
In its statement, the letter directly calls on AI developers to focus on “protecting humanity.”
“I would like to make a special appeal to those developing artificial intelligence,” Leo wrote. “Technological innovations can, in a sense, participate on behalf of humanity in the divine act of creation. As such, developers bear a special moral and spiritual responsibility because every design choice embodies humanity’s vision.”
This was not a verbal appeal from the Pope. Anthropic co-founder Chris Olah, whose San Francisco-based multibillion-dollar artificial intelligence company develops the large-scale language model Claude, joined Leo at the Vatican.
Theologians and clergy also sent greetings to the pope, who presented them with the Magnifica humanitas at around 11:30 a.m. local time on Monday.
What is an encyclical?
A papal encyclical is a letter from the Pope to all church leaders that contains the Pope’s interpretation of Catholic teaching. Leo XIV becomes pope in May 2025, and Monday marked his first encyclical as pope. Leo’s predecessor, Pope Francis, published four articles in October 2024, culminating in one titled “Dilexit nos,” which means “He loves us.”
Monday, however, was not the first time Leo has spoken about artificial intelligence during his papacy. The pope asked priests at a closed-door meeting in February to “resist the temptation” to use artificial intelligence to prepare sermons, Vatican News reported, adding that AI “can never share the faith.”
Leo is reported to have said: “Like all muscles in the body, if we don’t use them, if we don’t move them, they die. The brain needs to be used, so our intellect has to get a little exercise as well so we don’t lose that ability.”
On Friday, Leo spoke publicly at a Vatican conference on artificial intelligence, denouncing chatbots for exploiting the need for human connection.
“We are really experiencing a decline in what it means to be human,” Leo said on Friday.
