Denis Diderot was one of the leaders of the French Enlightenment thinkers known as philosophes. Diderot was arguably the most sophisticated and complex of all of the philosophes, and he was a prolific writer. Denis Diderot's works include writing on philosophy, science, literature, the arts, and his famous Encyclopedia, which marked him as a leader of Enlightenment thought.
However, he often goes under-recognized today. Here you can learn about Denis Diderot's biography, Denis Diderot's beliefs, and Denis Diderot's achievements and impact.
Denis Diderot Biography
Denis Diderot's biography begins with his birth in 1713 in the city of Langres, southeast of Paris. He studied philosophy and theology at a Jesuit university. He moved to Paris and took up the challenging life of a writer.
He struggled throughout the 1730s to make ends meet, genuinely living the stereotypical lifestyle of a broke and struggling aspiring writer before breaking it big in the 1750s. He did meet a wife and married in 1743. Soon after that, he had a daughter, who struggled to support.
In 1740 met Jean-Jacques Rousseau, and their conversation helped solidify Diderot's desire to continue working as a writer and intellectual. In the 1740s, he became increasingly well known as a philosophical essayist who was willing to push the boundaries and write about controversial subjects.
By 1749, he had become famous, even attracting the attention and praise of Voltaire, at the time the most famous of the French philosophers, or philosophies, as it is said in French. However, his willingness to write on controversial topics also caught the attention of the authorities. In 1746, some of his books were banned and burned; in 1749, he spent three months in prison.
After his release from prison, Diderot began work on his most famous project, the Encyclopédie. The publication of this work caused a firestorm of controversy, with Diderot and the other philosophes on one side and the institutions of the Church and the monarchy on the other. The project was complete and published clandestinely by 1765, and it helped launch Diderot to international fame.
Completing the massive project also freed Diderot to work on other works, many of which were only published after his death. When he had financial trouble, Catherine the Great of Russia stepped in and bought his library and gave him an annual pension, making him a wealthy man in his later years.
Diderot even visited Catherine in 1773-74 before retiring to Paris. He continued to write in this period, and his writings took on a more overtly political tone. He was highly critical of the Atlantic Slave Trade and all forms of top-down hierarchies, promoting radical egalitarianism and democracy.
Denis Diderot's biography ends with his death in Paris on July 31, 1784.
Fig 1 - Portrait of a young Diderot.
Denis Diderot's Beliefs
Denis Diderot's beliefs are connected to his leadership in promoting materialist philosophy. Diderot was at the forefront of the Enlightenment's application of the ideas of the Scientific Revolution to human society, using reason to interpret the world.
Materialist Philosophy:
Also known as materialism, this philosophy seeks to explain everything via the scientific process. Since everything in the world is made up of matter and particles, this philosophy holds that all phenomena, including politics, behavior, and even human conscience, are a result of physical, biological, and chemical interactions.
Denis Diderot's belief in the importance of reason also gave him a strong belief in empiricism, or that we learn through experience.
Denis Diderot's beliefs also consisted of a hefty dose of skepticism and eclecticism regarding religion, and he was highly critical of any dogma, whether religious, scientific, or philosophical. Denis Diderot's beliefs on religion gradually evolved from deism to atheism.
Deism:
A religious belief that there is a creator who made the world according to certain scientific rules or nature but does not interact with its functioning. The God of deism is sometimes referred to as a "clockmaker god," believing the world runs on its own in a logical way according to the way it was designed, similar to a clock.
Denis Diderot's beliefs on religion brought him into conflict with the Church. In fact, his application of reason and relativism to the concept of God in his essay entitled Lettre sur les aveugles ("Letter on the Blind") led to his imprisonment in 1749.
Now that philosophy is rapidly advancing; that it submits all the objects within its jurisdiction to its power; now that its tone is the prevailing one, and we are beginning to shake off the yoke of authority and example to hold to the laws of reason, there exists hardly a single elementary and dogmatic work with which we can be wholly satisfied."1
Fig 2 - A pensive Diderot.
Exam Tip!
Exam questions can ask you about the concepts of change and continuity. Think about how the Scientific Revolution of the 1600s promoted change in science and political ideas during the 1700s and how these ideas contributed to political change in the late 1700s and early 1800s. As you read this article on Denis Diderot, try to construct one historical argument on how the Scientific Revolution influenced the Enlightenment and one historical argument on how the Enlightenment influenced calls for political change using evidence found in the article.
Denis Diderot Achievements
Denis Diderot's achievements spread across an enormous range of genres, from theater and art criticism to literature to philosophy to science!
Denis Diderot's Encyclopedia
Denis Diderot's Encyclopedia, or Encyclopédie, is considered his greatest achievement. Denis Diderot's Encyclopedia was a collaborative project where different authors, philosophers, and scientists contributed articles.
The project began as a translation of Ephraim Chambers’ 1728 Cyclopedia, or Universal Dictionary of Arts and Sciences. However, as Diderot began work on it, it transformed into a larger, more ambitious project.
Denis Diderot's Encyclopedia had the express purpose of spreading and promoting reason as the torch that will light humanity the way, an idea in common with other philosophers of the Enlightenment. Diderot saw his Encyclopedia as a source of living knowledge that would challenge and change people's preconceptions.
It compiled articles from various authors, including Voltaire, Montesquieu, and Jean-Jacques Rousseau. Denis Diderot's Encyclopedia was published as a series of volumes over 15 years, from 1750 to 1765. When finally completed, Diderot's Encyclopedia had 28 volumes and over 70,000 distinct entries.
The Encyclopedia had an enormous impact and is rightly considered the greatest of Denis Diderot's achievements. It appeared at a time when intellectual thought was already challenging political, and Church authorities and only added to this current. It undermined the political and religious establishment, calling for religious tolerance and freedom of thought. It also celebrated and promoted science.
It made the ideas of the Enlightenment more accessible to many readers, and it is arguably the most important work of the entire period and part of the intellectual current that helped to spark the French Revolution a few decades later.
The encyclopedians successfully argued and marketed their belief in the potential of reason and unified knowledge to empower human will and thus helped to shape the social issues that the French Revolution would address...the Encyclopédie served to recognize and galvanize a new power base, ultimately contributing to the destruction of old values and the creation of new ones.”2
Other Denis Diderot Works
While the Encylopédie is undoubtedly the most well-known and greatest of Denis Diderot's works, he produced many more influential writings in their day. Below is a list of some other important works by Denis Diderot:
- Pensées philosophiques (Philosophical Thoughts) published in 1746
- French translation of the Dictionary of Medicine published from 1746-1748
- "Lettre sur les aveugles" ("Letter on the Blind") published in 1749
- "Le Fils naturel" (The Natural Son) published in 1757
- Jacques le fataliste (Jacques the Fatalist) published posthumously in 1796
- Le Neveu de Rameau (Rameau's Nephew) published posthumously in 1805
Fig 3 - An elderly Diderot.
Denis Diderot's Impact and Significance
Denis Diderot's achievements included an enormous contribution to the Enlightenment and intellectual currents developing in France and the rest of Europe during his lifetime. The Encyclopedia brought the ideas of Diderot and his contemporary philosophers to a much wider audience.
People across France read Diderot's Encyclopedia in salons and meeting rooms. His legacy contributed to a spirit of challenging the existing order of things. Even absolutist leaders like Catherine in Russia read his works and were influenced by them. It's hard to overstate just how impactful it was.
This growing atmosphere of challenge and desire for change was unleashed in the French Revolution, starting in 1789, just five years after Diderot's death. His more radical political views and atheism, as well as the complexity of his work, contributed to him taking a backseat to other more well-known Enlightenment thinkers like Voltaire, Rousseau, and John Locke. However, his impact on his time was still enormous.
Too systematically committed to his materialism, too vigorous in his irreligion, and too passionate and principled in his embrace of egalitarianism and universal democracy to be acceptable to anyone with the slightest worry about the rising tides of radical socialism and materialist free thought, Diderot became a pariah for many in nineteenth-century France and Europe...but recently scholars attuned to the very different character of philosophy and science in the eighteenth century have begun to return to Diderot’s work, finding in it the complex and sophisticated thinking that was his hallmark."3
Denis Diderot - Key Takeaways
- Denis Diderot's beliefs were firmly rooted in reason and philosophical materialism.
- Denis Diderot's achievements included many works, the most famous being the Encyclopedia.
- Denis Diderot's Encyclopedia compiled thousands of articles from different authors and was very influential in the spreading of Enlightenment ideas.
References
- Denis Diderot, Encyclopdie, Volume V, 1755.
- Clorinda Donato, The Encyclopédie and the Age of Revolution, 1992.
- Charles T. Wolfe and J.B. Shank, "Denis Diderot," The Stanford Encyclopedia of Philosophy (Spring 2022 Edition)
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