Denis Diderot

Denis Diderot a French philosopher, writer and editor (1713-1784), chief editor of the Encyclopedie, the great collaborative dictionary of arts, sciences and crafts that embodied the spirit of the French Enlightenment. He was a bold materialist thinker, a novelist and art critic of originality, and one of the most intellectually adventurous writers of his age.

Life and Free Thought

Denis Diderot was born in 1713 at Langres in Champagne, the son of a prosperous master cutler. He was educated by the Jesuits and, for a time, studied for the church, but he abandoned a clerical career for the life of a writer in Paris. He supported himself by teaching and by hack work, translating from English and writing essays on philosophy and mathematics.

His early book, Philosophical Thoughts, and the anonymous Letter on the Blind and Letter on the Deaf and Dumb established his reputation as an audacious thinker. The latter work, which argued that moral and metaphysical ideas depend on the senses and that a blind mathematician might reason differently about the world, provoked a scandal and briefly landed him in prison at Vincennes.

He lived for most of his life in difficult circumstances, dependent on patrons and on the income from his monumental editorial project. He corresponded widely, travelled to Russia at the invitation of Catherine the Great, and moved in the circle of the philosophes. He died in Paris in 1784, and many of his most daring works were published only after his death.

The Encyclopedie

The Encyclopedie, or Reasoned Dictionary of the Sciences, Arts and Crafts, was conceived by the publisher Andre Le Breton and entrusted to Diderot and the mathematician Jean d'Alembert as editors. It appeared in volumes between 1751 and 1772, and it grew into a vast survey of human knowledge, with contributions from many of the leading thinkers of France.

Diderot supervised the work with prodigious energy, commissioning articles, editing manuscripts, and himself writing on philosophy, art, mechanics and many other subjects. The Encyclopedie was more than a reference work: it was a vehicle for criticism and reform, attacking superstition, intolerance, obsolete law and privilege, and promoting science, industry and rational inquiry under the guise of neutral description.

The project was repeatedly threatened by censorship and by the hostility of the church and the state. D'Alembert withdrew as editor in 1758, and the royal privilege was revoked, yet the work was completed under difficult conditions. It was widely read and its doctrines circulated throughout Europe, making it one of the decisive instruments of Enlightenment opinion.

Materialism and Philosophy

Diderot developed a thoroughgoing materialism that denied the existence of God and of the soul as a separate substance. In works such as the Letter on the Blind and D'Alembert's Dream he argued that matter is inherently sensitive and active, that life emerges from the organisation of matter, and that the living being is a transformed whole rather than a composite of body and soul. These ideas were among the most radical of the century.

He denied both free will and the idea of a providential order. Nature, he held, is a perpetual becoming, and human beings are part of it, subject to its laws and shaped by their organisation and their circumstances. Morality rests for him on the natural sentiments of benevolence and on the interest of the species rather than on divine command, a position he explored in dialogue with his contemporaries.

His philosophical method was exploratory rather than systematic. He preferred dialogue, conjecture and the interplay of opposing views, and his works are full of digressions and surprises. This openness, together with his willingness to follow an argument wherever it led, gives his thought a modern and experimental quality.

Novels, Drama and Art Criticism

Diderot was a pioneer of the novel of ideas and of psychological realism. The Nun tells the story of a young woman forced into a convent and explores the cruelty of institutions and the ambiguities of desire; Rameau's Nephew presents a brilliant and unsettling dialogue between the narrator and a cynical parasite; Jacques the Fatalist is a playful narrative that questions causality and the conventions of fiction.

He wrote for the theatre and developed theories of drama that called for a more natural and morally serious stage, in which the situations of domestic life would replace the heroic conventions of classical tragedy. His plays were less successful than his theories, but his advocacy of the genre of serious comedy influenced the development of European drama.

As an art critic he wrote a series of reviews of the biennial salon exhibitions for a small readership in Germany, and in these letters he developed a vivid, impressionistic style of describing paintings that gave a new dignity to criticism as a literary form. His essays on beauty and on the pleasures of the senses connect his aesthetics with his materialism.

Influence and Legacy

Diderot's influence was felt through the Encyclopedie above all, which provided the Enlightenment with both an instrument of diffusion and a model of intellectual cooperation. Its articles on crafts and trades, on jurisprudence and on the sciences disseminated useful knowledge across Europe and helped to establish the ideal of public, secular learning.

His philosophical works, largely unpublished in his lifetime, were discovered with surprise by the nineteenth century and exerted a growing influence upon later European thought. His materialism, his skepticism about final causes and his evolutionary speculations anticipated themes of later science, while his novels attracted admirers from Stendhal to the modern novelists.

He is remembered as the organizing genius of the Encyclopedie and as one of the boldest minds of the French Enlightenment. A man of inexhaustible curiosity, he moved freely between philosophy, fiction, drama and criticism, and he gave eighteenth-century thought some of its most vigorous expressions. Modern scholarship has revealed a thinker more subtle and more original than the caricature of the mere editor of a dictionary.

See also

• Encyclopedie
• French materialism
• The philosophes
• Enlightenment