Encyclicals

From the Greek enkyklios to the pontifical circular letter

The word encyclical comes from the Greek enkyklios, "circular", through the ecclesiastical Latin epistola encyclica, "circular letter".^[1] The usage was not born in the Roman chancery: from Christian antiquity onward, bishops circulated among themselves common letters intended for several Churches at once, as opposed to a letter addressed to a single recipient. The Catholic Encyclopedia states it plainly: an encyclical is, in its strictest sense, "nothing else than a circular letter" — which from the outset distinguishes it from a finished theological treatise, a dogmatic definition or a disciplinary law.^[2] Historically, the episcopal use of the term preceded its exclusively pontifical use: it was only from the eighteenth century that the word came to designate a genre of act proper to the pope alone, addressed not to one diocese but to the universal episcopate.^[3]

A letter, not a treatise: the literary form of the encyclical

Formally, an encyclical has been distinguished from the other major pontifical acts by three stable traits since Leo XIII: it is written in the first person, in a tone of pastoral address rather than juridical definition; it bears a Latin title taken from its incipit — that is, from the opening words of the text —, not a thematic heading chosen after the fact; and it opens with a hierarchical list of addressees, from the patriarch down to the simple faithful, which evolved considerably in the twentieth century. The title is therefore never chosen to sum up the content: Rerum Novarum literally means "of new things", the opening Latin words of Leo XIII's text, from which no reader of the title alone could guess that it is a founding text on the condition of workers.^[4]

Benedict XIV and the encyclical Ubi Primum (1740)

The first document generally recognized as an encyclical in the modern technical sense was published by Benedict XIV, on 3 December 1740, only weeks after his election to the pontifical throne on 17 August of the same year. The Catholic Encyclopedia notes it in these terms: "Almost the first document published by Benedict XIV after his election was an 'Epistola encyclica et commonitoria' on the duties of the episcopal office."^[5] This text, known by its Latin title Ubi Primum, addresses to the bishops of Italy and the adjacent islands a series of pastoral recommendations — vigilance over doctrine, care of seminaries, struggle against disciplinary laxity — in a style still close to the traditional pastoral letter rather than to the great doctrinal document the encyclical would become a century later.

A genre still rare before Pius IX

Between 1740 and the mid-nineteenth century, the encyclical remained an occasional instrument: the popes of the eighteenth century and the early nineteenth century continued to prefer bulls, briefs and ordinary apostolic letters for most of their acts.^[6] Gregory XVI (pope from 1831 to 1846) published about ten of them, the most resounding of which — Mirari Vos — marked a turning point: it was the first time an encyclical was mobilized to condemn head-on the great political and religious ideas born of the European revolutions.^[7]

Mirari Vos (1832) against religious indifferentism

Published on 15 August 1832, Gregory XVI's encyclical Mirari Vos responds directly to the liberal Catholic movement led in France by Félicité de Lamennais, who demanded freedom of conscience, freedom of the press and the separation of Church and State as conditions for Catholic renewal.^[8] The text condemns what the pope calls indifferentismo — the idea that all religions are equal before God — and the consequence he draws from it:

"From this most corrupt source of indifferentism flows that absurd and erroneous opinion, or rather delirium, that freedom of conscience must be asserted and guaranteed to all." — Gregory XVI, encyclical Mirari Vos, no. 14, 15 August 1832^[9]

This condemnation, set back in its historical context of the throne-and-altar concordat of Restoration Europe, targets doctrinal indifferentism — the idea that no religion holds a monopoly on truth — and not, as has sometimes been read anachronistically, the civil religious freedom that Vatican II would later recognize in the declaration Dignitatis Humanae (1965) on different theological grounds, those of the dignity of the human person rather than those of the relativism of religious truths.^[10]

Quanta Cura and the Syllabus (1864)

Pius IX continued this line thirty-two years later with the encyclical Quanta Cura, published on 8 December 1864 — the anniversary of the proclamation of the dogma of the Immaculate Conception ten years earlier —, to which is annexed the Syllabus errorum, a list of eighty condemned propositions concerning the rationalism, political liberalism and religious indifferentism of the century.^[11] This technical and polemical document, which belongs to a particular literary genre (a list of condemned propositions without developed argumentation, closer to the doctrinal decree than to the narrative encyclical), is the subject of an Ignispedia article of its own.

📖 See the detailed article — The Syllabus of Pius IX (1864), for the complete analysis of the eighty condemned propositions and their historical reception.

A prolific pontificate (1878-1903)

It was with Leo XIII, elected on 20 February 1878 at the age of sixty-seven and deceased on 20 July 1903 after a twenty-five-year pontificate, that the encyclical truly became the ordinary vehicle of the great pontifical teachings.^[12] In a quarter of a century, Leo XIII published more than eighty-five encyclicals^[13] — on Christian philosophy, the rosary, Christian marriage, freemasonry, the Christian constitution of States, slavery, the unity of the Church and, of course, the social question — a pace and thematic diversity no pope has equalled since.

Aeterni Patris (1879) and the Thomist renewal

From the first year of his pontificate, Leo XIII published Aeterni Patris (4 August 1879), which officially relaunched the study of the philosophy of Saint Thomas Aquinas in Catholic seminaries and universities, after a century of relative disaffection for scholasticism.^[14]

"We warn all of you that nothing is dearer to Our heart, and that We desire nothing more than to see them furnish abundantly and copiously to studious youth the purest waters of wisdom, such as the Angelic Doctor pours forth in swift and inexhaustible streams." — Leo XIII, encyclical Aeterni Patris, 4 August 1879^[15]

This founding text of neo-Thomism largely explains why twentieth-century Catholic theology, down to Vatican II, remained structured by Thomist vocabulary and categories.^[16]

Rerum Novarum (1891), the charter of social doctrine

Leo XIII's most famous encyclical, and no doubt one of the most famous in all pontifical history, is Rerum Novarum, published on 15 May 1891. Faced with the industrial revolution and the impoverishment of workers, the text denounces both unbridled economic liberalism and the nascent collectivist socialism:

"The ancient workingmen's guilds were destroyed in the last century, and no other protective organization took their place. Public institutions and the laws have set aside the ancient religion. Hence, by degrees it has come to pass that working men have been surrendered, isolated and helpless, to the hardheartedness of employers and the greed of unchecked competition." — Leo XIII, encyclical Rerum Novarum, no. 3, 15 May 1891^[17]

This diagnosis, which lays the foundations of all modern Catholic social doctrine — just wages, workers' right of association, private property limited by its social function, subsidiarity of the State — deserves treatment of its own, so considerable is the text's influence on a century and a half of pontifical social teaching.

📖 See the detailed article — Rerum Novarum and the Social Doctrine of the Church, for the complete analysis of the text, its historical context and its doctrinal posterity down to Leo XIV.

Pascendi Dominici Gregis (1907) and the modernist crisis

Under Saint Pius X, the encyclical once again became the instrument of a major doctrinal condemnation. Pascendi Dominici Gregis, published on 8 September 1907, systematically analyses modernism — the theological current that subordinated Catholic dogmas to the evolution of religious sentiment and collective consciousness — and concludes with a formula that has remained famous:

"Now, embracing the whole system in a single glance, who will be surprised that We define it as the synthesis of all heresies?" — Saint Pius X, encyclical Pascendi Dominici Gregis, no. 39, 8 September 1907^[18]

This condemnation, prepared on 3 July 1907 by the Holy Office decree Lamentabili Sane and then completed, in 1910, by the anti-modernist oath imposed on the clergy, illustrates a use of the encyclical close to that of the Syllabus forty years earlier: identifying and refuting a system of errors deemed threatening to the integrity of the faith, rather than positively expounding a social or spiritual doctrine.

Quadragesimo Anno (1931) and the principle of subsidiarity

Forty years to the day after Rerum Novarum, Pius XI published on 15 May 1931 the encyclical Quadragesimo Anno, which updated Leonine social doctrine in the face of the 1929 economic crisis and formulated for the first time explicitly the principle of subsidiarity:

"Just as it is gravely wrong to take from individuals what they can accomplish by their own initiative and industry and give it to the community, so also it is an injustice and at the same time a grave evil and disturbance of right order to assign to a greater and higher association what lesser and subordinate organizations can do." — Pius XI, encyclical Quadragesimo Anno, no. 79, 15 May 1931^[19]

This principle of subsidiarity — not entrusting to a higher level what a lower level can accomplish by itself — would then irrigate all of Catholic social doctrine, down to being taken up into the law of the European Union half a century later, albeit in a narrower juridical sense than its original theological and anthropological scope.

Humani Generis (1950): what authority for an ordinary encyclical?

Pius XII's encyclical Humani Generis, published on 12 August 1950, is doctrinally important for two distinct reasons. On the one hand, it warns against certain tendencies in contemporary theology — the "new theology", an imprudent use of evolutionism applied to the origin of the human body, polygenism incompatible with original sin as taught by the Church. On the other hand, and this is the point directly concerning the status of encyclicals themselves, the text clarifies for the first time so sharply the doctrinal weight carried by an ordinary encyclical when the pope knowingly settles a question hitherto disputed:

"If the Supreme Pontiffs in their official documents purposely pass judgment on a matter up to that time under dispute, it is obvious that that matter, according to the mind and will of the Pontiffs, cannot be any longer considered a question open to discussion among theologians." — Pius XII, encyclical Humani Generis, no. 20, 12 August 1950^[20]

This principle, often summed up by theologians in the formula "a deliberate judgment closes the discussion", does not turn every sentence of an encyclical into an infallible definition: it only means that, when a pope deliberately chooses to settle a disputed point rather than mention it in passing, theologians can no longer treat it as an open question — without this amounting to an ex cathedra definition in the sense of Pastor Aeternus (1870). That is precisely the nuance distinguishing the second and third degrees of doctrinal assent, detailed in the article devoted to the documents of the Magisterium.

📖 See the detailed article — The Documents of the Magisterium, for the complete presentation of the three degrees of doctrinal assent (divine and Catholic faith, firm and definitive assent, religious submission) by which an encyclical can, according to its precise content, bind the faithful.

John XXIII: toward all men of good will

With John XXIII, the circle of an encyclical's addressees widened spectacularly. Mater et Magistra (15 May 1961) updated social doctrine for the era of decolonization and post-war economic growth. Above all, Pacem in Terris, published on 11 April 1963 a few weeks before the pope's death, innovated in its very opening address:

"To our venerable brothers, patriarchs, primates, archbishops, bishops and other ordinaries, in peace and communion with the Apostolic See, to the clergy and the faithful of the whole world, and to all men of good will." — John XXIII, encyclical Pacem in Terris, opening address, 11 April 1963^[21]

This was the first time an encyclical explicitly addressed, in its very heading, non-Catholic and even non-Christian recipients — a sign of a Church which, on the eve of Vatican II, opened itself to dialogue with the whole world on the great questions common to humanity, here international peace in the midst of the Cuban missile crisis.

Paul VI: Populorum Progressio and Humanae Vitae

Paul VI published seven encyclicals, two of which left a lasting mark on Catholic memory. Populorum Progressio, on 26 March 1967, extended social doctrine to the scale of the development of the peoples of the South, in the context of completed decolonization. Humanae Vitae, on 25 July 1968, reaffirmed on the contrary, against the expectations raised by the work of the pontifical commission on birth regulation, the traditional teaching on the illicitness of artificial contraception:

"This doctrine, expounded on numerous occasions by the Magisterium, is based on the inseparable connection, established by God, which man on his own initiative may not break, between the unitive significance and the procreative significance which are both inherent to the marriage act." — Paul VI, encyclical Humanae Vitae, no. 12, 25 July 1968^[22]

The text concludes, in the preceding paragraph, that "the Church, calling men back to the observance of the norms of the natural law, as interpreted by her constant doctrine, teaches that each and every marriage act must remain open to the transmission of life" (no. 11)^[23] — a principle which, from its publication onward, sparked significant theological contestation in several Western episcopal conferences, without the Holy See ever going back on the substance of this teaching, regularly reaffirmed since by John Paul II, notably in the apostolic exhortation Familiaris Consortio (1981) and the encyclical Veritatis Splendor (1993).

John Paul II, four major doctrinal encyclicals

John Paul II published fourteen encyclicals in twenty-seven years of pontificate, among which four major doctrinal texts stand out. Redemptor Hominis (4 March 1979), his first encyclical, presents Christ as the centre of Christian anthropology from the opening of his pontificate. Veritatis Splendor (6 August 1993) treats the foundations of moral theology and the existence of absolute moral truths, valid in every circumstance:

"The dialogue between Jesus and the rich young man goes on, in a certain sense, in every period of history, even in our own day." — John Paul II, encyclical Veritatis Splendor, no. 25, 6 August 1993^[24]

Evangelium Vitae (25 March 1995) develops the theology of human life, from conception to natural death, against what the text calls the "culture of death". Fides et Ratio (14 September 1998), finally, opens with one of the most quoted formulas of the contemporary encyclical corpus:

"Faith and reason are like the two wings on which the human spirit rises to the contemplation of truth." — John Paul II, encyclical Fides et Ratio, incipit, 14 September 1998^[25]

Benedict XVI, the trilogy on love, hope and truth

Benedict XVI structured his three encyclicals around the theological virtues and their social scope. Deus Caritas Est (25 December 2005), his first encyclical, opens with the founding Johannine quotation:

"God is love, and he who abides in love abides in God, and God in him." (1 Jn 4:16) — Benedict XVI, encyclical Deus Caritas Est, no. 1, citing 1 Jn 4:16, 25 December 2005^[26]

Spe Salvi (30 November 2007) develops a theology of Christian hope in the face of the ideologies of secularized progress. Caritas in Veritate (29 June 2009), finally, applies charity to the globalized economic and social order, in direct continuity with Populorum Progressio, more than forty years later.

Francis: faith, our common home, fraternity and the Heart of Christ

Pope Francis published four encyclicals that broaden the genre to global questions. Lumen Fidei (29 June 2013), his first encyclical, largely prepared by Benedict XVI before his renunciation and then completed by his successor, concerns faith as the light of existence, in the wake of the Year of Faith.^[27] Laudato Si' (24 May 2015), subtitled On Care for Our Common Home, joins a theology of creation to a critique of the technocratic development model:

"This sister now cries out to us because of the harm we have inflicted on her by our irresponsible use and abuse of the goods with which God has endowed her." — Francis, encyclical Laudato Si', no. 2, 24 May 2015^[28]

Fratelli Tutti, signed on 3 October 2020 on the tomb of Saint Francis of Assisi and published the next day, develops a reflection on universal human fraternity and social friendship, in direct continuation of the Document on Human Fraternity signed with the Grand Imam of Al-Azhar, Ahmad Al-Tayyeb, in Abu Dhabi in February 2019:

"This Saint of fraternal love, simplicity and joy, who inspired me to write the Encyclical Laudato Si', prompts me once more to devote this new Encyclical to fraternity and social friendship." — Francis, encyclical Fratelli Tutti, no. 2, 3 October 2020^[29]

Dilexit Nos (24 October 2024), finally, meditates on the human and divine love of the Heart of Jesus, reconnecting with the spirituality of the Sacred Heart carried by the twentieth-century popes before him.^[30]

The pope's ordinary magisterium, not a definitional act

Except in the rarest cases, an encyclical belongs to the ordinary magisterium exercised by the pope alone — not to the extraordinary magisterium exercised through a solemn ex cathedra definition or an ecumenical council.^[31] Canon 749 § 3 of the 1983 Code of Canon Law recalls that "no doctrine is understood as defined infallibly unless this is manifestly established"^[32] — a principle of prudence which forbids presuming a text to be infallible from the mere fact of its importance or apparent solemnity. In practice, an ordinary encyclical belongs to the third degree of assent described by the instruction Donum Veritatis (1990), no. 23 — a triptych resting on canons 750 and 752 of the 1983 Code of Canon Law and on the Professio fidei (1989 formula, completed by the motu proprio Ad tuendam fidem of 1998): the faithful owe it a religious submission of intellect and will, not an assent of theological faith.

📖 See the detailed article — The Documents of the Magisterium, for the complete exposition of the three degrees of doctrinal assent and their canonical basis (canons 750 to 754).

Doctrinal encyclical, social encyclical: two uses of the same genre

The literary form of the encyclical has historically served two fairly different uses, which do not exclude each other but colour the reception of the text differently. The doctrinal encyclical (Pascendi, Humani Generis, Veritatis Splendor, Fides et Ratio) clarifies, defends or deepens a point of theological or moral doctrine, often in reaction to an identified error. The social encyclical (Rerum Novarum, Quadragesimo Anno, Populorum Progressio, Laudato Si') applies the principles of Christian anthropology and morals to the concrete organization of society — labour, property, development, ecology. Some encyclicals, such as Caritas in Veritate or Laudato Si', deliberately hold both registers together, joining a theology of creation or of charity with concrete prescriptions for the world economic order.

The following table locates some major encyclicals according to their dominant register:

Can an encyclical define a dogma?

In practice, no encyclical has ever served to define a dogma in the strict sense fixed by the dogmatic constitution Pastor Aeternus of Vatican I (18 July 1870), which requires the pope to speak as supreme pastor and teacher, to engage his full apostolic authority, to pronounce on faith or morals, and to define — that is, to close the question by engaging the irrevocable adherence of the whole Church.^[33] The two Marian dogmas proclaimed since the nineteenth century — the Immaculate Conception (Pius IX, 1854) and the Assumption (Pius XII, 1950) — were thus promulgated not by encyclical but respectively by a bull (Ineffabilis Deus) and an apostolic constitution (Munificentissimus Deus), the most solemn forms of the pontifical documentary hierarchy.^[34][35] This distinction is no rhetorical accident: the very form of the encyclical — an explanatory pastoral letter, addressed to the episcopate to instruct and guide it — ill suits the solemn and brief act by which a pope defines ex cathedra a truth as henceforth belonging to the deposit of faith.^[36] Nothing would prevent in law an encyclical from containing, within itself, a passage fulfilling the conditions of an ex cathedra definition — but in fact, no pope has so far chosen this path for a definitional act.

The Latin title taken from the incipit

A constant rule, observed from Benedict XIV down to Francis, holds that the official title of an encyclical consists of its opening Latin words — the incipit —, whatever the language in which the preparatory draft was effectively written.^[37] Rerum Novarum means "of new things"; Pacem in Terris, "peace on earth"; Laudato Si', in Italian this time rather than Latin (a rare fact, explained by the quotation from Saint Francis of Assisi's Canticle of the Creatures), "praised be you". This convention immediately distinguishes the encyclical from other genres of pontifical documents whose title may be thematic (like certain instructions of dicasteries) rather than taken from the incipit.^[38]

Addressees: from the episcopal circle to all men of good will

The opening address of an encyclical — the list of its formal addressees, placed just after the title — has evolved considerably. Until the mid-twentieth century, it was typically limited to "patriarchs, primates, archbishops, bishops and other ordinaries in peace and communion with the Apostolic See", then to the "clergy and the faithful".^[39] John XXIII, with Pacem in Terris in 1963, added for the first time "all men of good will"^[40] — a formula taken up since by most social encyclicals, notably Laudato Si', which addresses itself explicitly, beyond Catholics, to "every person living on this planet", no. 3.^[41]

Language, translation and official publication

The reference text of an encyclical remains, by tradition, written or translated in Latin, the official language of the Holy See, then published in the Acta Apostolicae Sedis (AAS), the official gazette instituted by Saint Pius X through the decree Promulgandi Pontificias Constitutiones of 29 September 1908 and appearing without interruption since January 1909.^[42] It is this publication in the AAS which counts as the official text of the encyclical.^[43] In contemporary practice, the working text is most often written directly in the reigning pope's own language — Italian for John Paul II, Benedict XVI and Francis —, then translated into Latin for the official AAS version and simultaneously into the major international languages for immediate distribution, including on vatican.va.

The encyclical is only one genre among the dozen or so acts the Holy See can produce, and its doctrinal weight can never be deduced from its name alone. Three neighbouring genres, each treated in its own Ignispedia article, deserve brief distinction:

The apostolic constitution occupies a higher rank in the documentary hierarchy: it, and not the encyclical, serves the most solemn acts of government — dogmatic definitions, promulgation of codes of law, major institutional reorganizations.

📖 See the detailed article — Apostolic Constitutions, for the summit of the pontifical documentary hierarchy.

The motu proprio designates, for its part, an act the pope takes "on his own initiative", unsolicited, which today serves chiefly legislative and institutional reforms.

📖 See the detailed article — Motu Proprio, for the history of the genre and the inventory of the great contemporary motu proprio.

The apostolic exhortation, finally, encourages the faithful in a practice or extends the work of a Synod of Bishops, without engaging the same claim to systematic doctrinal exposition as an encyclical.

📖 See the detailed article — Apostolic Exhortations, for the post-synodal genre inaugurated by Paul VI in 1975.

For the complete mapping of all pontifical and curial acts — bulls, briefs, decrees, instructions, declarations, notifications — the hub article of the family remains the most complete entry point.

📖 See the detailed article — The Documents of the Magisterium, for the complete typology of all pontifical and curial acts and their respective degrees of authority.

An encyclical is neither a press release nor a mere dated pastoral opinion: it is an act of the pope's ordinary magisterium, whose reception engages, according to its exact content, a genuine religious submission of intellect and will — not an assent of theological faith, but no more a mere optional opinion among others.^[60] Reading an encyclical in its full text, rather than in the journalistic summaries that often retain a single sentence torn from its argumentative context, makes it possible to measure the overall coherence of a teaching often built, as in Rerum Novarum or Laudato Si', on several dozen structured paragraphs. The fact that nearly three centuries separate Benedict XIV's first modern encyclical from Francis's latest encyclicals, on subjects as diverse as religious indifferentism, the labour question, theological modernism, contraception, the relations between faith and reason, or integral ecology, testifies to a doctrinal continuity which the Catholic hermeneutic of continuity invites us to read as an organic development — not as a series of ruptures — of one and the same deposit received from the apostles.

• The Documents of the Magisterium — the complete typology of pontifical and curial acts and their three degrees of doctrinal assent.
• Rerum Novarum and the Social Doctrine of the Church — Leo XIII's founding encyclical (1891) and its posterity.
• The Syllabus of Pius IX (1864) — the eighty condemned propositions annexed to the encyclical Quanta Cura.
• The 1983 Code of Canon Law (Codex Iuris Canonici) — the juridical framework of canons 747-755 on the teaching office.
• Apostolic Constitutions — the summit of the pontifical documentary hierarchy.
• Motu Proprio — acts taken "on his own initiative" by the pope.
• Apostolic Exhortations — the post-synodal genre inaugurated in 1975.