Denis Diderot and the Banned Encyclopedia

Got something to say to this podcast? Send a voicemail, and you might hear yourself on the next episode!

In this episode of pplpod, we explore the life of Denis Diderot, the French philosopher who rose from poverty as a knife maker's son to edit the Encyclopédie, a work that challenged the foundations of the French monarchy and the Church. Born in Langres, he abandoned the Jesuit clergy and the law for a bohemian writing life in Paris, was disowned by his father, and married Antoinette Champion, a poor, devout older woman with no dowry. Living on tutoring and odd writing jobs, he wrote The Indiscreet Jewels on a dare from his mistress Madeleine de Puisieux, a scandalous novel that revealed his talent. A year later, his essay on a blind mathematician pushed him into dangerous territory, arguing that knowledge and morality come from physical biology rather than a providential god.

The episode follows his 1749 imprisonment at Vincennes, where he improvised ink from slate scrapings and wine and wrote in the margins of Milton's Paradise Lost. After his release, he turned the Encyclopédie into a vehicle for revolutionary ideas, elevating trades alongside philosophy and using cross-references to undermine orthodox views. The work was suspended, banned by the Church in 1758, and outlawed by the government in 1759, and d'Alembert withdrew. Diderot wrote around 7,000 articles himself, only to find that his publisher Le Breton had secretly censored the final volumes and destroyed the manuscripts. He then wrote for posterity, producing The Nun, Rameau's Nephew, the fourth wall concept, The Paradox of the Actor, and the Salon reviews. Catherine the Great bought his library and kept him as its librarian, and he visited her in 1773. He died in 1784, leaving a legacy of reason, subversion, and unfinished freedom.

In this episode we cover...

• The thigh-slapping debates with Catherine the Great, the Republic of Letters, and Diderot's youth in Langres as a cutler's son
• His break with his father, his marriage to Antoinette Champion, his poverty in Paris, and The Indiscreet Jewels written on a dare
• The 1749 Letter on the Blind, his theory of self-generating matter, and his imprisonment at Vincennes with slate ink and Paradise Lost
• The Encyclopédie, its alphabetical leveling of knowledge, cross-references, the 1758 and 1759 bans, d'Alembert's exit, Malesherbes's protection, and Le Breton's censorship
• His hidden works The Nun and Rameau's Nephew, the fourth wall, the Salon reviews, Catherine's patronage, his 1773 Russian trip, his 1784 death, the 1793 grave robbery, and his later reputation

Source credit: Research for this episode included transcript materials and supporting French Enlightenment, encyclopedic, theatrical, art criticism, Russian court, and biographical sources accessed October 31, 2026. Content is summarized and adapted for commentary and educational use.