Conceived by a Parisian printer as a modest business venture, a French translation of Ephraim Chambers' two-volume Cyclopaedia printed in London in 1728, the Encyclopédie far outstripped all initial plans. Entrusted to Jean le Rond d'Alembert and Denis Diderot, the project quickly took on vaster proportions, ultimately becoming one of the greatest commercial and intellectual enterprises of eighteenth-century France. The first volume of the work appeared in Paris in 1751. When the final volumes were completed two decades later in 1772, the Encyclopédie had grown to become the most massive single reference work in Europe. It comprised seventeen folio volumes containing 71,818 articles, eleven folio volumes of 2,885 plates, and five supplemental volumes. A group of more than 150 contributors supplied articles to the work, which was directed by Diderot alone after d'Alembert withdrew from the project in 1757. (Much of the work fell to Louis de Jaucourt, who some scholars have credited with more than 17,500 articles or 27 per cent of the total number.) The Encyclopédie was sold by subscription in France and throughout Europe to some 4,500 individuals. Prior to the French Revolution in 1789, five subsequent editions, either reprints or revisions, were produced in Italy and Switzerland, with roughly half of these 25,000 copies sold to readers in France.

But numbers alone only begin to tell the story of the Encyclopédie and its significance, both in the eighteenth-century socio-intellectual context and for us today.