Magnifica Humanitas — a Pope named Leo, again.

Every industrial revolution forces the same question on the Church: when the machines change the nature of work, what does the dignity of the human person still require?

In 1891, the steam engine and the factory had remade labor faster than any moral framework could follow. Men worked sixteen-hour days. Children worked beside them. Wages were whatever the market would bear, and the market would bear cruelty. Into that, Pope Leo XIII issued an encyclical that named the worker not as a unit of production but as a person with rights that no contract could erase. He called it Rerum Novarum — "of new things."

One hundred thirty-five years later, a new kind of machine is remaking work again. And a Pope has taken the name Leo.

Rerum Novarum — The Charter of 1891

Issued on 15 May 1891, Rerum Novarum is the foundational document of modern Catholic social teaching. Leo XIII refused both errors of his age: the unrestrained capitalism that treated the worker as a commodity, and the socialism that would abolish private property and dissolve the family into the state. Against both, he set the dignity of the human person.

His most enduring principle is the just wage — and he grounds it not in market sentiment but in natural justice:

"Let it be granted, then, that, as a rule, workman and employer should make free agreements, and in particular should freely agree as to wages; nevertheless, there underlies a dictate of natural justice more imperious and ancient than any bargain between man and man, namely, that the remuneration ought to be enough to support the wage-earner in reasonable and frugal comfort." Pope Leo XIII — Rerum Novarum (1891), §45

The encyclical defended the right to private property, the right of workers to form associations, the duty of the state to protect the vulnerable, and the priority of the family over the market. It is the seed from which a century of papal social teaching grew — Quadragesimo Anno (Pius XI, 1931), Laborem Exercens (John Paul II, 1981), Centesimus Annus (John Paul II, 1991, written for the centenary of Rerum Novarum itself), and now, in its own anniversary year, the first encyclical of Leo XIV.

What the Church Already Teaches on Artificial Intelligence

The encyclical does not arrive on empty ground. The Church's most developed magisterial statement on artificial intelligence is already in force: Antiqua et Nova, the "Note on the Relationship Between Artificial Intelligence and Human Intelligence," issued jointly by the Dicastery for the Doctrine of the Faith and the Dicastery for Culture and Education on 28 January 2025.

Its core distinction is simple and load-bearing: artificial intelligence is a tool, not a person. Machine intelligence can process and predict; it cannot understand, love, suffer, or seek the truth. Intelligence in the full human sense is bound up with the soul, with conscience, with relationship and the longing for God. To call a machine "intelligent" in the same sense as a man is a category error with moral consequences.

From that distinction, Antiqua et Nova warns against reducing the human person to data points, against displacing workers without regard for their dignity, and against the temptation to treat machine outputs as if they carried moral authority. The human person remains the subject of work — never merely its instrument. This is the bridge between 1891 and 2026: the same insistence on the worker as a person, applied to a machine Leo XIII could not have imagined.

Why This Lands on a Catholic Man Who Works for a Living

This is not an abstraction for theologians. The man who frames houses, drives the truck, writes the code, fills the prescription, or balances the books is the man whose trade is being repriced by a machine in real time. Catholic social teaching does not tell him whether to fear the machine or welcome it. It tells him something more durable: that his worth is not set by his productivity, that his wage is a question of justice and not only of markets, and that his first vocation — as a man, a husband, a father — is never reducible to his economic output.

St. John Paul II named the principle that holds all of this together, in Laborem Exercens §6: the priority of labor over capital — the worker is always the subject, never the instrument, of economic life. That is the lens through which a Catholic man reads any encyclical on AI and work. Not "will the machine take my job," but "what does my dignity require of me, and of those who employ me, no matter what the machine does."

Magnifica Humanitas — What Pope Leo XIV Wrote

Magnifica Humanitas ("magnificent humanity") — subtitle On Safeguarding the Human Person in the Time of Artificial Intelligence — was signed on 15 May 2026 and published by the Holy See on 25 May 2026. It opens not with the machine but with the human person before God, and the oldest of choices:

"Humanity, created by God in all its grandeur, is today facing a pivotal choice: either to construct a new Tower of Babel or to build the city in which God and humanity dwell together." Magnifica Humanitas — opening words

The encyclical unfolds in five chapters, framed by an introduction and a conclusion:

• I — A Dynamic Approach Faithful to the Gospel.
• II — Foundations and Principles of the Social Doctrine of the Church.
• III — Technology and Dominance: the grandeur of humanity in light of the promises of AI.
• IV — Safeguarding Humanity at a Time of Transformation: truth, work, freedom.
• V — The Culture of Power and the Civilization of Love.

A line that carries the whole argument — that no technology is morally weightless, because it always bears the imprint of the people and powers behind it:

"Technology is never neutral, because it takes on the characteristics of those who devise, finance, regulate and use it." Magnifica Humanitas

And on what the machine can never do — the encyclical's insistence that the human person is categorically more than any system that imitates intelligence:

"So-called artificial intelligences do not undergo experiences, do not possess a body, do not feel joy or pain, do not mature through relationships, and do not know from within what love, work, friendship or responsibility mean." Magnifica Humanitas — Chapter III

From there it grounds human dignity not in usefulness or output but in the person's very being. In the language of the Church's social doctrine, every human being holds an equal ontological dignity that no machine can confer, measure, or revoke — the same conviction Rerum Novarum defended for the worker and Dignitas Infinita (2024) restated for every person. The teaching is continuous with Rerum Novarum and Antiqua et Nova: the human person — never the machine, never the market — is the subject of work and the measure of every technology. Read the full encyclical, in the Pope's own paragraphs, at vatican.va.