The work was one of the Age of Enlightenment’s greatest creations, the Encyclopédie. Two decades after pen was first set to paper, the final volume, covering entries from Venerien (relating to Venus and fleshly pleasures) to Zzuéné (a town on the Egyptian Nile), was ready for the press. (Another 11 volumes of illustrations eventually followed.) That this herculean enterprise succeeded was nearly wholly the work of the letter’s writer: Denis Diderot.

TWO HUNDRED AND FIFTY years ago this month, a Parisian penned a letter to his lover. He filled it with sighs — although not over the depth of his feelings for his paramour. Instead, he sighed from the depth of despair over his professional plight. Yoked to a thankless task for more than 20 years, it was one that not only failed to make his fortune but also “nearly forced me to either flee France or lose my liberty.” Happily, he added, the end was in sight: “My great and cursed work is finished.”


One of the 18th century’s most original thinkers, Diderot was also the Encyclopédie’s principal editor and one of the most prolific contributors. Looking back, modern readers can see what Diderot could not. Far from being finished, the Encyclopédie had only begun its remarkable life.

Efforts to record all human knowledge stretch from Pliny the Elder’s massive “Natural History,” compiled in the first century AD, to the early 17th century and Francis Bacon’s “Great Instauration,” his encyclopedic project to arrange the fruit of empirical investigation on what he referred to as “the branches of the tree of knowledge.” (Bacon died before he could finish his work, contracting pneumonia after stuffing snow into a dead chicken to see how long he could preserve its flesh.) Bacon’s tree cast its long shadow into the next century, when the Scottish journalist Ephraim Chambers published his “Cyclopedia: Or, Universal Dictionary of Arts and Sciences.”


Not only had Chambers written the work alone — a performance, he modestly noted, “to which a Man’s whole Life seems scarce equal” — but he also launched a Rube Goldbergian series of events that led to the Encyclopédie.

Convinced there was a market in France for Chambers’s work, a group of French book publishers joined forces to translate it. Rather like today’s venture capitalists, they invested money with a succession of editors, each of whom proved either incompetent, untrustworthy, or both. Doubling down on their initial investment, the desperate publishers took a remarkable gamble: Along with the mathematician Jean d’Alembert, they hired Diderot, a young and obscure provincial, recently arrived in Paris, to co-edit the encyclopedia.

Indeed, obscurity was the least of Diderot’s dubious qualities. More worrisome, certainly, was his intellectual radicalism. By the mid-1750s, when he leapt at the publishers’ offer, Diderot had already published a number of works that outraged throne and altar in Ancien Regime France. An ancestor to Eve Ensler’s “Vagina Monologues,” Diderot’s biting satire of French court life, “Indiscreet Jewels,” tells of the contrasting experiences and worldviews of more than two dozen women as told by their vaginas. Even more disturbing, at least for the Catholic Church, was his “Letter on the Blind,” a short story in which Diderot invites the reader to see the world with the eyes, as it were, of a blind man. Given his lack of sight, this character conceives of not just the world, but also of God in a way terribly different from the rest of us. As the man tells his interlocutor, “If you wish me to believe in your God, you must make me feel him.”


As it turned out, Diderot was himself a little blind: How could he not see the trouble he was courting? The rumblings of skepticism and materialism in his books, like that of his fellow philosophes, threatened to undermine the country’s political and religious authorities. Shortly after he became co-editor of the Encyclopédie in 1749, these same authorities had Diderot arrested and tossed into prison. While his wife and friends panicked, his publishers ran around Paris with their wigs on fire, as they explained to court officials that they had sunk 250,000 livres in the affair — roughly $3 million. They insisted that Diderot was essential to an enterprise that would bring France not just glory but also revenue. Their pleas prevailed, and Diderot was released three months later. And he proved his editors right: The Encyclopédie did bring renown to France, but not the sort his watchers reckoned on.

Diderot did not translate Chambers’s work; he transformed it. The Encyclopédie is no more a compendium of facts and figures than Paris is a collection of boulevards and buildings. In fact, consider city streets: They will, if we let them, lead us to destinations entirely new and unexpected. So, too, with Diderot’s conception of his encyclopedia. Rather than take us from point A to B, it takes us to points where we did not expect to go, but reason and curiosity insist we go. In his entry “Encyclopédie” — where else? — Diderot revealed that his aim was to assemble the knowledge scattered across the world to guarantee that “the work of centuries past is not useless to centuries to come, and that our descendants, by becoming more learned, may become more virtuous and happier.”


Some of the early pioneers of the Internet — especially those connected, like Stewart Brand and Kevin Kelly, with Wired Magazine — might well see themselves in this description. Their goals were not unlike Diderot’s — to create webs of communication, community, and complicity among individuals — just as their fundamental convictions resembled the Frenchman’s — that human beings are basically good, that free discourse is essential to democracies, that skepticism towards established authority is a good and great thing, and that rational behavior makes for human happiness.

From his own recent experiences, Diderot understood the risks involved. (In fact, after Volume Two appeared, Louis XV, under the sway of the reactionary church, put a temporary kibosh on the enterprise. It was, remarkably, thanks to the support of the official censor, Chrétien-Guillaume Lamoignon de Malesherbes, that Diderot and his colleagues were able to break this half-court press and continue, in semi-clandestine circumstances, to publish the remaining volumes.)

Despite these obstacles and dangers, Diderot managed to shape the Encyclopédie according to his deeply democratic values. On subjects too sensitive to critique, such as religion and politics, Diderot used an approach we might call à l’Onion. Orthodox experts were called upon to write on subjects like “soul” and “angel,” producing articles of such stupefying scholasticism that they seem like self-parodies.


* But Diderot did not stop there. The Encyclopédie was conceived as a fully interactive text. At times, he tacks on his own commentaries, marked by an asterisk, which send up the incongruities and lunacies lacing the original articles.At other times, Diderot appends his era’s own version of hyperlinks, cross-listings, which take the reader to other “sites” in the encyclopedia that contradict the original entry — so that, as he wrote, the “entire mud edifice” of baseless claims will collapse into a “vain heap of dust.”

And this remarkable editor is not above tossing around a bit of dust himself. Scratching his head over the entry “Aguaxima,” Diderot erupts into a “Whhaat?” moment. He knows it’s a Brazilian plant, but nothing else. Why then, he asks, should be bother to include it? Not for native Brazilians, who already know more about the plant than he does. Not for his fellow French, who couldn’t possibly care. But there it is, in Volume One, for one simple reason: “To oblige those readers who prefer finding nothing in an article, or even finding nonsense, than not finding an article at all.”

In many ways, this has become us: Mesmerized by the limitless offerings of our virtual world, we prefer anything to nothing and nonsense to sense. Here’s the great difference between the Encyclopédie and the Internet, between what reading meant then and what it increasingly passes for today. While Diderot encouraged differences of opinion and perspectives among his closest contributors, he knew that all of them — from Voltaire to Rousseau, Baron d’Holbach to the Chevalier de Jaucourt — took the act of writing as seriously as did those who read it. No activity was more noble. It served to illuminate and enlighten, not distract and dumb-down. When the last volume finally rolled off the press, the Encyclopédie contained more than 70,000 articles written by hundreds of contributors, all of whom either wittingly or unwittingly advanced this ideal. Notwithstanding Diderot’s lament, to what more useful and glorious activity could one devote a life?

* Think of Jon Stewart mugging while he replays a Fox News report.

Robert Zaretsky is professor at the University of Houston and is author most recently of “Boswell’s Enlightenment.”

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