Denis Diderot
Denis Diderot was a prominent French philosopher and writer of the Enlightenment, best known for his role as co-editor of the influential "Encyclopédie," a comprehensive work that challenged traditional authority and emphasized reason and empirical knowledge. Born in 1713 in Langres, France, to a family of tradesmen, he initially pursued a religious career before turning to letters and philosophy. Diderot's intellectual journey was marked by his skepticism toward religion, leading to a gradual abandonment of Catholicism and a focus on morality shaped by social experience rather than dogma.
Throughout his life, Diderot produced a wide array of works, including philosophical essays, dramas, and critiques of art, showcasing a deep engagement with ideas about virtue, emotion, and the human experience. His writings often reflected a tension between reason and passion, illustrating his evolving thoughts on creativity and morality. Diderot's assertive stance against autocracy and his advocacy for freedom of thought were significant during a time of rigid societal structures.
Despite facing censorship and imprisonment for his radical views, Diderot's contributions to literature and philosophy established him as a pivotal figure in shaping modern thought. His legacy endures, as he is celebrated for his courage to question norms and his influence on subsequent generations of thinkers and writers.
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Denis Diderot
French philosopher and writer
- Born: October 5, 1713
- Birthplace: Langres, France
- Died: July 31, 1784
- Place of death: Paris, France
As editor of and contributor to the Encyclopedia, Diderot codified and promulgated the views of the French Enlightenment. His posthumously published fiction, moreover, has earned for him a prominent place in the pantheon of eighteenth century writers, and his philosophical works remain challenging and influential.
Early Life
The son of Didier Diderot, a master cutler, and Angélique Vigneron Diderot, a tanner’s daughter, Denis Diderot (duh-nee dee-droh) was born into a family of tradesmen. In addition to this trade connection, quite a few of his relatives had entered the Church, among them the canon of the cathedral at Langres. Diderot’s brother, Didier-Pierre, and his sister, Angélique, would follow this ecclesiastical path, the former becoming a priest and the latter a nun. Diderot, despite his later atheism, also showed early religious inclinations. Tonsured at the age of twelve, he made the 150-mile (240-kilometer) journey north to Paris three years later to study at the Jesuit Collège de Louis-le-Grand or the Jansenist Collège d’Harcourt; he may have taken courses at both. When he received his degree in 1732, though, it was from the University of Paris, and his interest had shifted to philosophy and rhetoric.

Since Diderot had abandoned a career in the Church, his father apprenticed him to the Parisian lawyer Clément de Ris. This field suited him no better than religion, however, and after enduring two years of legal studies, Diderot turned to a life of letters. His father refused to approve of so uncertain a course, so for the next decade, Diderot survived on the meager earnings he garnered as a tutor and hack writer, supplemented by occasional small sums from his mother. On November 6, 1743, he married Anne-Toinette Champion, the daughter of a poor linen-shop owner; the marriage further alienated his father, who so opposed it that he had Diderot locked up in a monastery to prevent the wedding. Diderot escaped; he realized, however, that he could not rely on his parents to support his family and recognized that he needed a secure source of income.
Life’s Work
Denis Diderot turned to the booksellers, offering his fluency in English and his literary talent. In 1743, he translated Temple Stanyan’s Grecian History (1707) for a publisher named Briasson, who was sufficiently pleased with the result to ask Diderot for a French version of Robert James’s Medical Dictionary (1743-1745). At the same time that he was translating James’s treatise, he adapted the third earl of Shaftesbury’s An Inquiry Concerning Virtue or Merit (1699). Much in Shaftesbury’s work appealed to Diderot and deeply influenced his views. He admired the Englishman’s tolerance and emphasis on reason, and he adopted the notion that religion and morality should be judged according to their social effects. Diderot also agreed with Shaftesbury that emotions play an important role in fostering socially proper conduct. He was less prepared to accept Shaftesbury’s optimism, his notion of innate aesthetic appreciation, and his criticism of organized religion.
Diderot’s first original philosophical work, Pensées philosophiques (1746; English translation, 1819), which was written over Easter weekend, 1746, to earn fifty gold pieces for his mistress Madame de Puissieux, was built on his encounter with Shaftesbury’s text. Diderot was still not prepared to reject the Church—the fifty-first pensée reaffirms his belief in Catholicism—but he does urge that faith be tested by reason and that the passions, deemed by the orthodox to be dangerous, be seen as necessary to morality and creativity. Published anonymously, it was sufficiently impressive to be attributed to such well-known intellectuals as Voltaire or Étienne Bonnot de Condillac. It was also regarded as sufficiently radical to be condemned by the Parlement of Paris in July, 1746.
La Promenade du sceptique (wr. 1747, pb. 1830; the skeptic’s walk) revealed Diderot’s increasing doubts about religion; the manuscript was seized before publication, and the police began to watch Diderot closely. His bawdy satire on Louis XV and Madame de Pompadour, Les Bijoux indiscrets (1748; The Indiscreet Toys, 1749), further antagonized the authorities, and his Lettre sur les aveugles (1749; An Essay on Blindness, 1750; also as Letter on the Blind, 1916), which questioned the Deistic argument that cosmic order proves God’s existence, led to his arrest and solitary confinement for three months in the fortress of Vincennes.
Diderot’s imprisonment shook him deeply. Previously, he had published his controversial works anonymously; henceforth, he would rarely publish them at all. His reputation in the eighteenth century, therefore, was lower than it would become after his death. Much of his contemporary acclaim derived from the project that would occupy him for the next fifteen years: His translations and other writings not only had exposed Diderot to new knowledge but also had made him a logical choice to be coeditor with Jean le Rond d’Alembert of the ambitious project to translate and supplement Ephraim Chambers’s five-volume Cyclopaedia: Or, Universal Dictionary of the Arts and Sciences (1728). The finished work, comprising seventeen volumes of text and eleven volumes of plates, was published as Encyclopédie: Ou, Dictionnaire raisonné des sciences, des arts, et des métiers (1751-1772; partial translation Selected Essays from the Encyclopedy, 1772; complete translation Encyclopedia, 1965).
As conservative opponents, who twice succeeded in having the Encyclopedia condemned, realized, the work was not an innocent compilation of existing knowledge. In its pages, nature replaced Providence and determinism superseded God’s will as the guiding forces of the world. Instead of relying on authority and tradition, Diderot and his fellow philosophers urged readers to judge by experience and experimentation. In a world of monarchies, the article “Political Authority” proclaimed that “no man has received from nature the right to command other men. Freedom is a present from heaven, and every individual of the same species has the right to enjoy it as soon as he enjoys reason.” By 1758, d’Alembert was sufficiently frightened by official reaction to the Encyclopedia to resign as coeditor, leaving Diderot with the sole responsibility for writing and soliciting contributions to complete the massive project.
In the midst of these labors, Diderot found time to produce a number of other works. The theater had long interested him. Late in life, he would state that he had debated between studying at the Sorbonne and becoming an actor, and in his Lettre sur les sourds et muets (1751; Letter on the Deaf and Dumb, 1916) he claimed to know much of French drama by heart. In the latter half of the 1750’s, he indulged his interest by writing two plays, Le Fils naturel: Ou, Les Épreuves de la vertu (pr., pb. 1757; Dorval: Or, The Test of Virtue, 1767) and Le Père de famille (pb. 1758, pr. 1761; The Father of the Family, 1770; also known as The Family Picture, 1871). As the subtitle of Dorval reveals, Diderot regarded these works, as he did all of his writings, as having a moral purpose. In an article in the Encyclopedia, he had spoken of actors’ ability to engender in audiences the love of virtue, and an essay on Geneva by d’Alembert, also in the Encyclopedia, urged the city to permit dramatic productions because they promote morality.
In addition to reforming society, Diderot hoped that his plays would alter theatrical techniques and practices, which he regarded as unrealistic. To the published version of each play he added comments on stagecraft, urging actors to pretend that no audience faced them. He wanted the people onstage to interact naturally with one another, not perform for observers. Diderot also argues, in Paradoxe sur le comédien (wr. 1773, pb. 1830; The Paradox of Acting, 1883), that the actor must be ruled by the intellect rather than by his emotions if he wishes to convey passion consistently. This view incidentally might suggest that Diderot was beginning to question his earlier agreement with Shaftesbury on the primacy of sentiment in guiding action.
Questioning does not, however, mean rejecting. As he matured, Diderot would become increasingly skeptical—of his own views as well as the views of others, stating that “skepticism is the first step toward the truth.” In Le Neveu de Rameau (1821, 1891; Rameau’s Nephew, 1897), he seems to prefer Apollonian reason to Dionysian passion, but he also acknowledges the necessity of emotion for creativity. This same ambivalence shows itself in the aesthetic criticism that he wrote for Friedrich Melchior Grimm’s Correspondance littéraire, a newsletter that circulated in manuscript, from 1759 to 1781. In an essay from 1766 on painting, Diderot instructed artists, “Move me, astonish me, rend me; make me shudder, weep, tremble; fill me with indignation.” At the same time, he recognized that reason must balance enthusiasm.
Though uncertain about the means by which art should achieve its effects, Diderot had no doubt that its end must be the promotion of virtue. Hence, for example, he preferred the sentimental paintings of Jean-Baptiste Greuze to the more sensuous works of François Boucher. Greuze appealed to the heart, Boucher only to the eye. Similarly, though he was an atheist, he admired religious art, because it inspired virtuous feelings.
By the time his role in the Encyclopedia ended in 1765, Diderot had gained the reputation of being an important French intellectual. A flattering sign of Diderot’s growing reputation came from Jean-Honoré Fragonard and Russia’s Catherine the Great. In his series of paintings honoring the various arts, Fragonard chose Diderot to represent literature. His hair short, his forehead high, his mouth turned up in an enigmatic smile of reason, the philosopher holds a volume of the Encyclopedia and appears to be a Roman citizen wearing an eighteenth century dressing gown. Catherine the Great relieved Diderot of financial concerns in 1765 by buying his library for fifteen thousand livres and appointing him as its curator for life at a salary of another one thousand livres a year. She agreed not to take formal possession until after Diderot’s death.
In 1773, Diderot went to Russia to thank the empress for her patronage. The trip inspired a number of works reflecting on politics and education, and during this time Diderot probably completed his best-known novel, Jacques le fataliste et son maître (wr. c. 1771, pb. 1796; Jacques the Fatalist and His Master, 1797). A clever, picaresque work, it once more reveals Diderot’s skepticism. Although he had, like Jacques, believed in determinism earlier in his life, he now questioned this view. Despite Jacques’s claim that no one has free will, he behaves in the novel as if he can choose whatever course of action he wishes to pursue, and authorial intrusions indicate that chance rules the world. Readers may draw their own conclusions—or conclude nothing.
Similar doubts characterize other writings of this period. “Beware of those who impose order,” Diderot warned in Supplément au voyage de Bougainville (1796; Supplement to Bougainville’s Voyage, 1926). The dialogue form, which Diderot used repeatedly, allows for the presentation of various positions without requiring the author to endorse any. This method, drawn from Plato, appealed to Diderot because it was safe should authorities secure a copy of the manuscript, and it also permitted Diderot to explore various viewpoints. Est-il bon? Est-il méchant? (pr. 1781, pb. 1834; is he good? is he mean?), his last and best play, questions, without deciding, whether one can be virtuous if one performs good deeds in a manner that embarrasses their beneficiaries. Skeptical to the end, Diderot’s last words to his daughter were, “the first step toward philosophy is disbelief.”
Significance
Since his death on July 31, 1784, Denis Diderot’s reputation has grown. With the benefit of the perspective brought by time, one can recognize the truth of Carl Becker’s observation that Diderot epitomized his age, both in the profundity of his thought and in the occasional shallowness of his observations. One can appreciate more fully his courage in speaking out, guiding the Encyclopedia to completion despite an official ban, telling Catherine the Great that she should abandon autocracy for democracy, and the like. One of his essays was sufficiently bold in its criticism of the ancien régime to earn for him a severe reprimand from the police commissioner of Paris. With the publication of many of his best works, one can at last see his greatness as a writer as well as a thinker.
Even more important to the increasing appreciation of Diderot is the fact that his empiricism and skepticism matched the modern mood. In his own day, Voltaire referred to him as Socrates, a name that fits well. Like Socrates, Diderot questioned the accepted wisdom of his day, risked much for his beliefs, and contributed to the intellectual progress of his age. Writing of eccentrics, Diderot remarked, “If one of them appears in company, he is like a piece of yeast which ferments and restores to everyone a portion of his natural liberty. He shakes and stirs things up; he calls forth praise and blame; he brings out the truth.” In these lines from Rameau’s Nephew, Diderot wrote his own epitaph.
Bibliography
Becker, Carl. The Heavenly City of Eighteenth Century Philosophers. New Haven, Conn.: Yale University Press, 1932. Classic source on eighteenth century philosophes, placing Diderot in the context of the general Enlightenment project of building a new ideal on the wreckage of medieval philosophy.
Blom, Philipp. Enlightening the World: “Encyclopédie,” the Book That Changed the Course of History. New York: Palgrave Macmillan, 2005. Relates the history of the Encyclopedia, describing the book’s conception, efforts to suppress its publication, and the authors who faced exile, jail, and censorship to complete the work.
Blum, Carol. Diderot: The Virtue of a Philosopher. New York: Viking Press, 1974. Focuses on Diderot’s concern for a moral life and his intellectual quest to define what such an existence involves. A well-written study that draws on biography, letters, and published writings. Makes some useful comparisons between Diderot and Jean-Jacques Rousseau on the nature of virtue.
Brewer, Daniel. The Discourse of Enlightenment in Eighteenth-Century France: Diderot and the Art of Philosophizing. New York: Cambridge University Press, 1993. Describes how French Enlightenment writers attempted rationally to critique and to demystify all knowledge. Focuses on Diderot, discussing his experiments in applying Enlightenment critique to his studies of philosophy, science, and fine arts.
Darnton, Robert. The Business of Enlightenment: A Publishing History of the “Encyclopédie,” 1775-1800. Cambridge, Mass.: Harvard University Press, 1979. This massive, prizewinning history of Diderot’s great project is an important contribution to the growing number of studies devoted to publishing, bookselling, the reading public, and similar topics, placing ideas in the context in which they are disseminated. Illustrated, with a narrative bibliography and an index.
Fellows, Otis. Diderot. Boston: Twayne, 1977. A chronological overview touching briefly on almost all Diderot’s works. Stresses Diderot’s modernity and traces the evolution of his thought. A helpful, annotated bibliography concludes the work.
France, Peter. Diderot. New York: Oxford University Press, 1983. A good, short introduction concentrating on Diderot’s ideas. Arranged topically rather than chronologically, covering Diderot’s political, social, and aesthetic views. Includes a useful bibliography with brief annotations.
Furbank, P. N. Diderot: A Critical Biography. New York: Alfred A. Knopf, 1992. Survey of Diderot’s life, focusing on an examination of his major works. Furbank argues that Diderot’s ideas anticipate the philosophies of later French thinkers.
Undank, Jack, and Herbert Josephs, eds. Diderot: Digression and Dispersion, a Bicentennial Tribute. Lexington, Ky.: French Forum, 1984. Presents nineteen essays that cover Diderot’s many activities and interests. In their diversity, the contributions mirror the editors’ view that Diderot did not seek unity but rather regarded diversity as the rule of nature.
Wilson, Arthur M. Diderot. New York: Oxford University Press, 1972. The definitive biography. Places Diderot within the context of the Enlightenment and emphasizes his courage in remaining the editor of the Encyclopedia. Considers the development of Diderot’s ideas on such matters as religion, emotion and reason, order and diversity, determinism, and chance.