The history of the Encyclopédie is a rattling good tale, and Philipp Blom tells it beguilingly. Originally conceived as a modest translation of the Chambers Cyclopaedia, the great work changed its character once Diderot and d'Alembert appeared. Its aims from the outset in 1751 were not only to present knowledge in a methodical way but also to exploit that knowledge so as to "shake off the yoke of authority and tradition" and "to change the common way of thinking". As such, it was controversial from Day One, a target for attacks from the establishment of Church and Crown, culminating in a complete ban in 1759. But despite this setback, the Encyclopédie eventually proved unstoppable. Too much money was bound up in it to let it go abroad, too many livelihoods (about a thousand) were involved. D'Alembert had departed, but Diderot remained, to see it through, with the help of a false foreign imprint and a resolutely blind eye from the authorities. The final volumes of text appeared in 1765, the illustrative plates in 1772. It has been called, with reason, an epic of the modern age: 28 volumes, nearly 73,000 articles, 20 million words, and arguably the greatest achievement of the whole Enlightenment period.

Philipp Blom brings an elegant pen to this complex and diverse picture. Setting the scene in eighteenth–century Paris, whose life and manners he imaginatively portrays, he recounts the story with generous digressions to include not just the main actors but also thumbnail sketches of many on the periphery, like Grimm or Morellet or Mme d'Epinay. Consequently, the book becomes a rich account of events and attitudes in France during the quarter century of the Encyclopédie years.

There are two heroes: Diderot primarily, but also Jaucourt, who arrived late but was to become the true workhorse of the whole project. The study shapes itself essentially around Diderot, from earliest days in his native Langres right through to his rather melancholy ending a decade after the Encyclopédie had been completed. Diderot came to resent the burden which had taken up too much of his life, the more so as mentality had not evolved for the better as much as he had hoped. Perhaps, however, this is to paint rather too dark a picture. For the editorship had also given him a standing of eminence amongst his peers, at home and also abroad, notably with his great patron Catherine the Great.

The author describes the Encyclopédie as "the last great documentation of the customs, the tools, the thoughts, the aspirations, and the limitations of Europe before 1789". All this is true. But as a summing up of an achievement he has so fully presented, this errs somewhat on the tepid side. Admittedly, the Encyclopédie is not a revolutionary document, and the attacks on the Church by Voltaire or the seminal discussions of social inequality by Rousseau are much bolder. Nor is it a homogeneous whole, as was inevitable with well over a hundred contributors, and it had to contend throughout with oppressive censorship. But its general thrust is firmly anti–clerical and anti–Christian, it strongly pleads for religious toleration and, albeit cautiously, expresses scepticism about absolute monarchy. Its very publication was a political act, as the authorities were not slow to appreciate.

Given the large area which he covers, Philipp Blom is impressively accurate. But there are some exceptions when he is off centre. Rousseau is described as a "despiser of women", which surely even his most feminist opponents would have to agree is not only harsh but false. Nor does his Emile treat father and daughter, but tutor and tutee. Worse still befalls Voltaire, whose "enlightened blindness to all things human (!)" is evidently felt to be less than endearing. Even Voltaire's splendid campaign on behalf of Jean Calas is grudgingly conceded as though he were a minor participant. The bibliography, so richly appointed for most others, is swept bare for Voltaire. So it is not too surprising to learn that this man, who was, with intermittent absences, a Parisian for his first half century and longer, apparently lived not in Paris but in Geneva (where in actual fact he spent less than five years).

Blemishes of this kind detract from but fortunately do not destroy the excellence of so much else in this welcome volume.

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