What is an encyclical? From workers’ rights to artificial intelligence, five papal letters that have impacted the world
Pope Leo XIV on Monday released his first encyclical, “Magnifica Humanitas,” or “Magnificent Humanity,” expressing his vision for human dignity in the age of artificial intelligence.“The document, presented at the Vatican with Anthropic founder Christopher Olah, highlights how the Catholic Church continues to use one of its oldest forms of communication to address modern social and ethical challenges.An encyclical is a formal letter written by the pope, usually addressed to bishops around the world. These documents are used to provide authoritative teaching on important moral, social, or political issues. Although they do not have the legal status of papal bulls, Catholics are encouraged to use them as guidance in their daily lives.Although popes have been writing to the faithful since the church’s earliest days, Pope Benedict XIV, who led the church from 1740 to 1758, is credited with shaping the encyclical into the form recognized today.“According to its etymology, an encyclical (from the Greek egkyklios, kyklos meaning round) is nothing more than a circular letter. In modern times, the use of the term is almost entirely restricted to certain papal documents that differ in technical form from the ordinary style of bulls or communiqués and that are expressly addressed in their titles to the Patriarchs, Primates, Archbishops and Bishops of the Universal Church in communion with the Apostles. Voila. According to the Catholic Encyclopedia, encyclicals are sometimes addressed, with exception, to the archbishops and bishops of a particular country.Leo XIV’s Magnifica Humanitas now joins a series of influential encyclicals that have sparked debate within and outside the Catholic Church.
Five Important Encyclicals
1. “Rerum Novarum” (1891) – On workers’ rights During the Industrial Revolution, Pope Leo XIII promulgated “Rerum Novarum,” meaning “the new,” which became the basis of modern Catholic social teaching.The document defended workers’ rights, including the right to form unions and earn a living wage, while rejecting socialism and laissez-faire capitalism. It also inspired a broader social justice movement within the church, The New York Times reported.It was this encyclical that inspired the current pope to choose the name Leo XIV. The Pope officially signed the Magnifica Humanitas on May 15, 2026, the anniversary of Rerum Novarum, although it was not publicly released until 10 days later.2. “Peace on Earth” (1963) – On World Peace “Pacem in Terris” or “Peace on Earth” was written by Pope John XXIII during the Cold War and is addressed not only to Catholics but to all humanity.The encyclical called for a ban on nuclear weapons and set out the idea of a global public institution dedicated to the “universal common good”, with the United Nations seen as a first step.It also urged people to participate in public life “and work together for the benefit of all mankind.”When it was published, the New York Times published the full text.3. “Human Life” (1968) – On Birth Control Pope Paul VI’s “Humanae Vitae,” meaning “human life,” reiterated the Catholic Church’s opposition to artificial birth control.The core teaching of the document states that every act of sexual intercourse must avoid intentional prevention of conception.The encyclical immediately sparked a debate among Catholics that has raged for decades. A majority of Catholics in the United States and Latin America believe the church should allow artificial birth control, according to a 2024 Pew Research Center poll.To help stop the spread of AIDS, many bishops later provided qualified support for condom teaching.4. “Charity in Truth” (2009) – On Economics In “Caritas in Veritate,” or “Charity in Truth,” Pope Benedict XVI calls for a major rethinking of the global economy amid growing economic inequality.The encyclical criticized the growing gap between rich and poor, urged ethical behavior in the financial industry, and called on businesses to take greater social responsibility.Like “Pacem in Terris,” it advocates for a global political authority to help regulate the economy, according to the New York Times.Many scholars praised the document for its reflections on love, truth, and justice, but critics said the document was difficult to read due to its dense language and broad subject matter.5. “Laudato Si” (2015) — About the environment Pope Francis’ “Laudato Si,” which means “Laudato Si,” means “Laudato Si,” is the first encyclical to focus entirely on the environment.The document sees caring for the planet as a moral and spiritual obligation, not just a political, scientific or economic matter. Francis also highlighted the links between climate change, poverty and social instability.The encyclical had an impact on the global environmental movement, although Francis later lamented in a 2023 document that little progress had been made on ecological issues.With Magnifica Humanitas, Leo XIV now ranks artificial intelligence alongside workers’ rights, peace, the economy, birth control and climate change as issues addressed by the papal encyclical, continuing a tradition that has shaped Catholic teaching for centuries.
