Let us begin with last words, or at least the last words spoken in his daughter’s hearing by one of France’s greatest thinkers and one of its most congenial spirits, Denis Diderot. In 1784 the ailing 71-year-old philosopher was lodging in a fine house on the rue de Richelieu on Paris’s right bank, the rent of which was paid partly by his friend Catherine the Great of Russia. Diderot’s daughter, Marie-Angélique de Vandeul, visiting him on July 30th of that year, was pleased to find him holding court amidst a group of friends and in full, unstoppable voice. As she was leaving she heard him paraphrase a quote of his own from years before: “The first step towards philosophy is incredulity.”
Next day, at table, he helped himself from a dish of stewed cherries, against his wife’s advice – “What the devil type of harm can it do me now?” he demanded – and in the act of reaching out for more fruit, died. As his latest biographer, Andrew Curran, has it: “While having anything but a heroic death à la Socrates, Diderot had nonetheless expired in a way that was perfectly compatible with his philosophy: without a priest, with humour, and while attempting to eke out one last bit of pleasure from life.”
The pleasure to be derived from life was one of Diderot’s chief preoccupations, a thing that cannot be said of many philosophers. Socrates insisted the unexamined life is not worth living; Diderot would have said the same of the unenjoyed life. He loved to be among his friends, eating, drinking, swapping witticisms, and above all, talking. When he was at the Empress Catherine’s court in St Petersburg it was said she complained of a constant small pain in her knee where the visiting savant used to tap her hard with a fingertip to emphasise the profusion of points he had to make to her – in the end she made him sit at the other side of a table so that he could not get at her.
Yet the empress was impressively, and uncharacteristically, loyal to him, providing funds for his work on the great ongoing Encyclopédie, affording him shelter at her court when the French authorities were after his blood, and, as we saw above, providing comfort for him and his family in his last days.
Critical insight
He was born in the town of Langres, in the Champagne region, some 270km southeast of Paris. His father, a cutler, was a simple man of high moral character, whom Diderot revered throughout his life, despite the fact that they did not see much of each other and that Diderot père at one point had his son incarcerated in a monastery to prevent him marrying a woman the family deemed unsuitable. Diderot’s later notoriety as an atheist must have caused deep distress to his pious father, not least because in his early days in Langres young Denis had considered becoming a priest. He soon changed his mind, however, and set off for Paris and, supposedly, a career in law.
Enrolled at the Sorbonne, Diderot arrived at what his biographer describes as a “critical insight”, which was that “reasonable people had the right to subject religion to the same scrutiny as any other human tradition or practice. Seen from this critical angle, the Catholic faith itself could be rationalised, improved, and perhaps even discarded”. To make such an insistence and others like it was a highly dangerous thing to do in France in the closing decades of the ancien régime, and it was inevitable that Diderot would find himself at odds with the powers-that-were.
Which he duly did, to his own surprise, which in turn surprises us. Did he really imagine that publications such his novel The Nun, which inter alia exposes sapphic passions rife within a number of France’s convents, and another novel, the mischievously erotic Les bijoux indiscrets, in which a sultan’s magic ring compels women’s genitalia to recount their adventures – the latter work, admittedly, be came bitterly to regret having published – would not get him into trouble?
And then there were the many thousands of articles he contributed to the Encyclopédie, the “Enlightenment bible”, in the composition of which he was the intellectual, and practical, mainstay. This was labour he both gloried in and resented, since within the pages of its multiple volumes he was free to expound some of his most shocking philosophical, religious and social doctrines, even though it kept him from his own work, and probably damaged his health.
Fraught venture
In this wonderfully lucid and lively biography, Andrew Cullen adroitly traces the triumphs and miseries of the Encyclopédie. It was a fraught venture, but the result was a work that changed the world, or at least changed the way in which the world is conceived. Knowledge, Diderot and his fellow encyclopaedists showed, was power. How ironic, therefore, that the revolutionary leaders in 1789 should have denounced Diderot as an enemy of the people, given that he was the man who had written the famous line: “And with the guts of the last priest let us wring the neck of the last king.”
Such sentiments have led some latter-day commentators to deplore Diderot and his fellow philosophes, especially Voltaire and Rousseau, as the originators of pernicious doctrines the dire consequences of which did not end with the Terror of the 1790s in France, but can be traced even in the violent Islamism of our own day.
In his early years in Paris, studying at the Sorbonne and scraping a living as best he could – sometimes by fraudulent means – the Jesuit-educated Diderot began seriously to question not only the foundations of organised religion, but the very existence of God. If for him incredulity was a spur to philosophise, scepticism was “the first step towards truth”.
Solitary confinement
He was not the only thinker of his time to entertain such notions – Voltaire was his near-contemporary, after all. However, while Voltaire was a lifelong deist – that is, he believed in God but not in religion – Diderot’s scepticism was radical and thoroughgoing. In time he became a famous, and infamous, atheist. As Curran puts it, “at age 32, the author of Philosophical Thoughts [Diderot’s first original and highly controversial book] no longer had any need for Roman Catholicism and its spiteful trickster of a God”.
One can imagine what the political establishment of the day thought of such a work. The police were soon on Diderot’s case, and after a number of more or less friendly warnings – this was France, after all – the scandalous anti-Christ was imprisoned at the Château de Vincennes east of Paris. At first he was kept in solitary confinement, though later he was moved to more comfortable quarters, with access to the prison gardens.
His time in jail had a profound effect: as a result of it the former firebrand turned down the heat, to the extent of leaving many of his more radical works unpublished. “And yet,” as Curran writes, “if the state effectively put an end to his public career as a writer of audacious, single-authored books, Diderot nonetheless intended to disseminate the joys of freethinking even more boldly upon his release from Vincennes. The labyrinthine Encyclopédie, as it turned out, would provide just the right venue.”
Yes, but the works he wrote in his own name are among the most profound, the most provocative and the most entertaining of the Enlightenment era. His masterpiece is surely the short novel Rameau’s Nephew, in which this convinced rationalist insouciantly rocks the foundations of rationalism itself. For readers new to Diderot, Rameau’s Nephew is a good place to start, though they should be prepared to have their most comforting convictions shied at like so many Aunt Sallys. Diderot himself must have been shocked at what he had wrought in this book, yet it is a ringing testament to what his biographer identifies as “his lifelong tendency to embrace existence fully, completely, and audaciously, with little regard for the potential consequences”.
