Denis Diderot

Denis Diderot (Langres, 1713 – Paris, 1784) was one of the central figures of the French Enlightenment. A writer, art critic, translator and philosopher, he is best remembered for directing the Encyclopédie together with Jean le Rond d'Alembert. His thought belongs to the materialist and sensualist tradition, and his most original contribution is a sustained reflection on how reason and sensibility depend on one another in our knowledge of the world and in our conduct.

He was born into a family of craftsmen: his father was a master cutler, and his mother came from a tanner's household. He was educated by the Jesuits in Langres and later in Paris, where he took a master's degree in arts and enrolled in law, though he soon gave up the prospect of a clerical or legal career. When he chose to live by writing, his father disowned him, and for about a decade he lived a bohemian life, translating English and medical works and publishing articles. In 1743 he married Anne-Antoinette Champion, a woman of modest background, and the marriage was not a happy one. Diderot had several relationships over the years, the most documented being his long correspondence with Sophie Volland.

His early original writings, such as the Philosophical Thoughts (1746), argued for a reconciliation of reason and feeling: without sensibility there is no virtue and no sublime work, but without reason feeling can become destructive. In The Skeptic's Walk (1747) he staged a dialogue between a deist, an atheist and a pantheist, a device he would return to. The Letter on the Blind (1749) showed his conviction that our ideas depend on the senses, and it led to his imprisonment, which made him more cautious afterwards. The bawdy novel The Indiscreet Jewels (1748) brought in some income, but his name became linked above all to the Encyclopédie, published from 1751. The work aimed to gather the knowledge of its age, to give due weight to the mechanical arts, and to spread a critical spirit against religious and political authority. Its secular tone earned it the hostility of the Church and the government, and many contributors withdrew. D'Alembert left in 1759, and Diderot remained as sole editor, writing a large share of the articles himself.

His view of nature moved towards a non-dogmatic materialism. In his scientific writings, which ranged over chemistry, physics, mathematics, natural history and medicine, he held that science seeks less the why of phenomena than the how. Between 1754 and 1765 he developed the notion of universal sensibility, according to which sensitivity is a property of matter itself, which would explain life. In late works such as D'Alembert's Dream, Rameau's Nephew and the Paradox of the Actor, most of them published after his death, he developed a dialogic and paradoxical style of thought that is now regarded as among his most original achievements.

His finances were precarious for much of his life, and he received little official recognition. In 1766 he sold his library to Catherine the Great of Russia, who left it in his keeping and paid him an annual sum. In 1773 he spent several months in Saint Petersburg, where he talked with the empress and wrote texts for her. He died in Paris on 31 July 1784. His influence reaches the bourgeois drama, art criticism and later materialist thought, and the Encyclopédie is today seen as one of the intellectual forerunners of the French Revolution.