Think of Diderot and you think of the Encyclopédie (1751-72), 28 volumes containing nearly 72,000 articles, including 11 volumes of illustrative plates. A monumental achievement of human intellectual endeavour and, as Curran notes, the encyclopaedia:

“Is now considered the supreme achievement of the French Enlightenment: a triumph of secularism, freedom of thought, and eighteenth-century commerce.”

And yet Curran also tells us that:

“On a personal level, however, Diderot considered the dictionary to be the most thankless chore of his life.”

Of course, he didn’t have the benefit of hindsight. The twenty plus years Diderot put into the opus were intellectually rewarding but the Encyclopédie was spied upon, obstructed, censored, misconstrued, vilified and suppressed. It was the source of a diplomatic dispute with Switzerland and Diderot’s hopes for a Russian edition, promised by Catherine the Great, were never realised. Diderot must have found it hard to disentangle the battle from the scholarship:

“What Diderot did not fully realise, in 1765, was that he had carried the ideas of the Enlightenment forward in a way that no person, not Voltaire, and certainly not Rousseau, had done before.”

Curran’s portrait of the man and his work reveals that there is so much more to him than editor of the Encyclopédie and author of The Nun and Jacques the Fatalist. Diderot was a sexologist, an anti-colonialist, an art critic; a genius and a man with feet of clay.

This timely biography is also an exploration of the Age of Enlightenment. How would we refer to our own times: the age of disillusionment? As we face bleak political choices, growing prejudice and entrenchment in the West. Curran notes that one thing Diderot did for people was to make us more sceptical and yet we seem more susceptible to dumbing down, fake news and indifference. I’m not hankering for a return to the eighteenth century; universal poverty, autocratic sovereign rule, or even the simplicity of later pre-digital times. Yet, despite political and religious oppression the Enlightenment happened and that was down to Diderot and individual voices that stood up for intellectual freedom, they were inspirational, and goodness knows, we could do with more of that in this uninspired age.

Denis Diderot was born in Langres to Didier and Angélique on 5th October, 1713, in a house on the place Chambeau, since renamed Place Diderot. Now, with a statue of Diderot in pride of place, nearly a quarter of the shops in the square bear his name, including a café and a motor bike shop. His father was a cutler, but it was clear that Denis was not cut out for that, and so he was sent to be educated for the priesthood. After obtaining his bachelor’s degree, Denis attended the Sorbonne, Paris, qualifying for the priesthood but he chose to leave before committing to the vocation. Diderot soon discovered he was not cut out for the law either but he was moderately successful as a translator, tutor and sermon writer. He wouldn’t know wealth until he began working for Catherine the Great.

Why Diderot renounced the priesthood is not clear, but Curran is thorough in his analysis of Diderot’s studies with the Jansenists and the Jesuits, who offered diametrically opposed ideas on the path to religious fulfilment. This disagreement must have opened up a fissure in Diderot’s mind, within which atheism and secular ideas of life developed, he was determined to expose the hypocrisy and inconsistencies of religious belief. He early work, Letter on the Blind, expressed atheistic ideas, it was circulated anonymously and questioned the need to look beyond nature to find explanations for it, Curran states:

“He then supplied the answer: we have created this illusory myth so that we may flatter our own supposed self-importance.”

Blasphemous, subversive and ill-timed (France was suffering from an economic decline and defeat in war), Letter on the Blind landed Diderot in jail. A writ of incarceration signed by Louis XV meant there was no need for a trial and handed down an indeterminate sentence. Diderot had no choice but to admit authorship of Letter to the Blind and affirm that he would not publish heretical writing or contravene good morals in future. He spent 102 days in prison learning a hard lesson, many of his more ‘heretical’ writings were not published in his life time (he left a wealth of material behind).

Released in 1749, he returned to the Encyclopédie, Diderot was not the originator of the project, but, was certainly, it’s most important editor. Previous dictionaries had been attempted but none with the ambition, vision, completeness and academic rigour of the Encyclopédie. Diderot provided a substantial amount of the entries, and most of those displaying original thought, he also called on a number of experts from many fields to contribute: geography, natural science, botany, mathematics, medicine, philosophy, art, linguistics, grammar etc. Curran makes it clear from the evidence that Diderot was the driver of the project. The Encyclopédie was not just a dictionary but a revolutionary exploration of ideas, satirical and witty, a condemnation of authority and closed thinking: “… Inviting its readers to cultivate a critical viewpoint.”

Definitions challenged religious and conservative norms. Religion and superstition, for example, were seen as contiguous practices. The Encyclopédie was finished in 1772, despite the interventions of the censors, the parliament, and the Jesuits. Madame de Pompadour was an early fan; this and a reaction to religious fanaticism, after an attempted regicide, may have helped sway the king toward allow the project to proceed.

Curran writes extensively on Diderot the playwright, his promotion of naturalism and exploration of an entirely materialist understanding of the universe. Also, Diderot the sexologist and Diderot the opponent of colonialism and slavery; it’s morality and the probability of cultural annihilation. Prophetically Diderot suggested a black Spartacus would rise in opposition to slavery – later fulfilled by Toussaint Louverture.

Diderot cultivated those he saw as enlightened rulers, particularly Catherine the Great, becoming the empress’s art buyer alongside Golitsyn, the Russian Ambassador to France. He later travelled to Russia in 1772, becoming a confidant of the empress, writing several essays on enlightenment themes and spending many hours in conversation with her before they fell out. The relationship soured as Catherine saw Diderot’s theories as unworkable in practice.

Diderot returned to France in 1774. The last two great works of his life were The Nun, an out and out attack on religious vocation and the perils of the closed community and sexual perversion, and Jacques the Fatalist. Diderot was a great admirer of America, “a land of tolerance”, but, although his writing influenced the America Revolution, he was never able to visit. Diderot died in 1784:

“I do not flatter myself into thinking that, when the great revolution comes, my name will still survive…”

Which was true, in so far as Diderot was not seen as a driving force for the revolution of 1789. He was too closely associated to the aristocracy and Robespierre saw the supreme being as a guarantee of the transcendence of citizens and the justification of the terror, purifying the body politic. Although the Church’s view of Diderot held sway for some time he was eventually seen as the revolutionary force for free thinking and human intellectual development.

Curran’s biography is a triumphant work; it is detailed, and meticulously researched, this study tells us about the man and his work. About the many strings to his bow, reminding us he was more than the author of the Encyclopédie. Curran captures the complexity of the man, the contradictions that, for me, make him all the more human and important as a philosopher. Curran captures the genius, but also the complex contradictory man, his sometimes reactionary views on sexuality, for instance, although he was bound by the belief that:

“Nothing that exists can be against nature or outside nature…”

Diderot was also a rather conservative art critique and a serial philanderer, a man of passions as well as intellect.

This book encapsulates the social and intellectual life of the century, in France and in a wider European context. Showing how the work of Diderot, Rousseau and Voltaire coloured the age. At the time the Encyclopédie was being compiled Dr. Johnson was preparing his English dictionary (1755). While Johnson’s is one of the most amazing works completed by a one hand and is undoubtedly a masterly piece of scholarship, Curran demonstrate how much more ambitious and comprehensive the Encyclopédie is. Diderot and the Art of Thinking Freely is an intelligent and highly readable biography.

Andrew Curran is the William Armstrong professor of humanities at Wesleyan University.

Paul Burke 5/4

Diderot and the Art of Thinking Freely by Andrew S. Curran
Other Press 9781590516706 hbk Jan 2019