Francis Bacon’s purpose in writing the Instauratio magna was “to commence a total reconstruction of sciences, arts, and all human knowledge, raised upon the proper foundations” in order to restore or cultivate a just and legitimate familiarity between things and the mind. Only a small part of this enormous work was ever completed, but the author had planned 130 sections divided into three main sections: external nature, man, and man’s action on nature. From its proposed contents Bacon’s intention was clearly to compile an encyclopaedia thoroughly scientific in character—“a thing infinite and beyond the powers of man”—that he himself recognized to be revolutionary in character. His most important contribution was, however, the devising of a new and thoroughly sound classification of knowledge that bears a remarkable resemblance to the classification put forward by Matthias Martini in his Idea Methodica (1606). Although Bacon was apparently unaware of this work, both philosophers were probably working from the same basic Platonic precepts. The results were profound: Diderot made a point of acknowledging the assistance Bacon’s analysis of the structure of human knowledge had afforded him in planning the contents of the Encyclopédie, and Samuel Taylor Coleridge hailed “the coinciding precepts of the Athenian Verulam and the British Plato.”

Only two more Latin encyclopaedias of any importance followed. Antonio Zara, bishop of Petina, compiled the Anatomia Ingeniorum et Scientiarum (“Anatomy of Arts and Sciences”; 1614), which was chiefly remarkable for the inclusion of an index. And Johann Heinrich Alsted, who, like Martini, came from Herborn, compiled an Encyclopaedia (1630) whose arrangement corresponds broadly to Matthias’s classification of human knowledge.

Zara’s and Alsted’s encyclopaedias were organized systematically by classification. The turning point came with Louis Moréri’s alphabetically arranged Grand Dictionnaire historique (1674), which was especially strong in geographical and biographical material. Its success was immediate; six editions were issued by 1691, each incorporating much new contemporary information. English editions followed in 1694, 1701, and (a supplement) 1705. Other encyclopaedias in England, Germany, Switzerland, and the Netherlands acknowledged its inspiration. The alphabetically arranged encyclopaedia in the vernacular had almost won the day, in spite of the German scholar Daniel George Morhof’s modest success with his ill-balanced Polyhistor Literarius, Philosophicus, et Practicus (“Literary, Philosophical, and Practical History”; 1688–1708).

If there was any doubt concerning the more popular form of the encyclopaedia, the issue of Antoine Furetière’s Dictionnaire universel des arts et sciences (1690) confirmed the true nature of public taste. Furetière not only compiled a fine encyclopaedic dictionary, but he emphasized the arts and the sciences, thus reflecting the rapidly growing public interest in modern culture, science, and technology. If confirmation were still needed, the Académie Française’s commissioning of Thomas Corneille to compile Le Dictionnaire des arts et des sciences (1694), with its thorough and authoritative treatment of these new encyclopaedic features, demonstrated that even the more conservative scholars were by now keenly aware that a new spirit had arisen. The period of the clerical encyclopaedia had ended, as the Franciscan friar Vincenzo Maria Coronelli found when his Biblioteca Universale Sacro-Profano (1701–06) ceased publication at volume 7 of a projected 45.

Pierre Bayle, in his Dictionnaire historique et critique (1697), achieved a most remarkable tour de force. Although his encyclopaedia purported to be an updating of the information in Moréri, the entries were largely unexceptionable. The real originality of his work lies in the profuse and scholarly footnotes and the commentaries that at times were an amazing mixture of skepticism, blasphemy, and ribaldry. Bayle challenged orthodox ideas; his brilliant mind spared nothing. This approach heralded that of Denis Diderot, and the distinguished writers who revised later editions—Prosper Marchand and Pierre Desmaizeaux—continued in the same style.

The Lexicon Technicum (1704) of John Harris represented the powerful impact of the work of the Royal Society (founded 1660). Here was all the equipment of the modern encyclopaedia: excellent engraved plates, clear practical text, bibliographies appended to the more important articles. So far, England had had to make do with translations of French encyclopaedias. Harris’s emphasis on the need to include scientific and technical subjects helped to reverse the trend. This process was completed by the issue of Ephraim Chambers’s Cyclopaedia (1728). Like Harris, Chambers omitted people in favour of more information on the arts and sciences, and he paid more attention to clear expositions of ancient and modern philosophical systems. His admirably cross-referenced work is universally recognized as the father of the modern encyclopaedia.

The French were well aware of these developments. By 1744 five editions of Chambers’s Cyclopaedia had been issued. The Paris publisher André Le Breton saw a ready market for a translation. The first proposals were a failure, however, and Diderot was enlisted to plan what at that time was still essentially a translation on a much broader basis. Under the hands of Diderot and Jean Le Rond d’Alembert the concept changed. The Encyclopédie (1751–65) was a philosophical undertaking carried out on a gigantic scale, and much of the writing was of a high standard. To the orthodox, it appeared that the project had got out of hand, but there were 2,000 subscribers to the first volume, and the subsequent scandals over the irreverent, authority-challenging articles only added to the number of purchasers. The equivocal attitude of high dignitaries in both church and court and the growing public dislike of the encyclopaedia’s chief critics—the Jesuits—led to a complex situation in which official disapproval and substantial private encouragement caused the production and fortunes of the Encyclopédie and its producers to lurch dangerously from one crisis to another. Curiously, Diderot did nothing to further the physical development of the encyclopaedia; his contribution was to fire men’s minds with a willful guidance that conformed to the country’s increasingly revolutionary spirit. As Voltaire said: “this vast and immortal work seems to reproach mankind’s brief life span.”