ENCYCLOPÆDIA. — In the history of culture, this term is commonly used, without further specification, to denote the *Encyclopédie ou dictionnaire raisonné des sciences, des arts et des métiers*, by Diderot and d’Alembert (Paris 1751–72), on account of its importance in the history of modern thought.
There are, however, precedents or forerunners of this undertaking: mention must be made of Ramsay, who advocated the idea within Masonic circles; the Parisian *Société des arts* of the Count of Clermont; but above all the proposal made in 1745 by the Englishman J. Mills to the Parisian publisher Le Breton, to translate, with G. Sellius, the English *Cyclopædia* of E. Chambers (2 vols., London 1728). Le Breton clashed with Mills and in 1746 entrusted the translation to Diderot under the direction of the mathematician Gia de Malves, with d’Alembert overseeing the scientific part. It was to Diderot and d’Alembert, who took charge of the project in 1747, that the credit is due for giving it far greater significance, persuading the publisher to expand the work, to include original articles, and to distribute them among various contributors—each occupying his own sphere and thus serving the general interest of humanity (Diderot, *Œuvres*, XIV, p. 421). Diderot revealed the academic nature of the enterprise and excluded direct protection by the state; d’Alembert, at least in part, echoed this in his *Essai sur la société des gens de lettres et des grands* (1752). Thus the *Encyclopédie* became a great cultural undertaking, an expression of mature French Enlightenment. Its distant model was still the *Dictionnaire historique et critique* of B. Bayle (1695–97; 5th ed., 1734), which had initially been conceived as a “register of errors” to teach doubt. Now, from Bayle’s doubt there seems to have arisen a new passion and almost a new form of certainty, tending to become positive-empirical, yet not entirely detached from Cartesianism, drawing on Newton and Leibniz, while elevating Locke’s associationism to the status of a dogma.
Among the early contributors were the abbés de L’Epée—for theological and belles-lettres articles—and de Prades, Yvon, and Pestre, who took over the theological entries; the grammarian de Marsais, an atheist and Cartesian; Toussaint and Raynal. The patriarchs of French Enlightenment (Voltaire, Montesquieu) cautiously joined later, after 1752. The success of the enterprise was furthered by the benevolent tolerance of Chancellor d’Aguesseau—succeeded by Malesherbes as director of the *librairie* after 1750 and until 1763. There was thus a climate of understanding between the *Encyclopédie* and the authorities; yet Diderot was conscious of the now inevitable rift between the *philosophes* and the monarchy in France. D’Alembert, by contrast, held up as a model of the enlightened sovereign Frederick the Great of Prussia (e.g., in the entries *Académie*, *Dictionnaire*).
The *Encyclopédie*’s earliest adversaries were the Jesuits, who published the *Journal de Trévoux*; they immediately perceived its dangerous character and helped provoke the first condemnation in 1752. The resumption of publication, authorized by the government, was a victory for the *philosophes* and their opponents among the Jesuits. The latter soon fell victim to the converging hostility of Enlightenment thought and radical Gallicanism in the Parlements. D’Alembert’s pamphlet *Sur la destruction des Jésuites en France* (1765) is a triumphant cry from the *philosophe* and testifies to the discredit into which religious quarrels had brought the Church (G. Goyau). Public opinion was now ready to embrace the legend of the great Jesuit conspiracy. In education, d’Alembert could already argue for complete secularization (following La Chalotais) and propose the idea of a secular catechism of morals (*Œuvres*, I, p. 231).
After overcoming a second crisis in 1758–59 (in 1758 Helvétius’s *De l’Esprit* unleashed storms upon the *philosophes*), the *Encyclopédie* was completed in 1765 (when the final volumes of text appeared) and in 1772 (when the last of the plates were issued). The complete original edition comprises 17 volumes of text, 12 of plates, and 4 of supplements (1777).
The famous *Discours préliminaire* by d’Alembert, prefixed to the first volume, contains many of the work’s guiding ideas: simple erudition must give way to a philosophical science of principles; one must
> “ascend to the origin and generation of our ideas” (here drawing on Bacon’s classification of the sciences, which takes on new meaning and links up with the characteristic dogmatism of associationist doctrines); it is necessary, moreover, “to accumulate facts” and thus proceed through historical-positive analysis to free the original truth from the erroneous traditions of ignorance and superstition.
Thus the faith in experimental observation, shining forth through the *esprit de méthode*, is wedded to absolute confidence in universal rationality, acting immanently in the laws of the cosmos and in human nature (cf., e.g., the entries *Leibniz*, *Raison* in Diderot; in the entry *Cosmologie* d’Alembert adopts Leibniz’s idea of universal continuity; Turgot transfers it to the historical sphere and partly rehabilitates the Middle Ages, which the other encyclopedists had radically depreciated). D’Alembert starts from the “regeneration of ideas” of the Renaissance: he extols the fecundity of modern thought over against scholasticism, praises Bacon’s method, the negative and critical side of Cartesian thought, the “philosophy” of Newton, and Locke’s metaphysics, which he defines as an “experimental physics of the soul.” In conclusion, he alludes to the controversy opened by Rousseau on the progress of the arts and sciences (Rousseau contributed the entries on music and *Économie politique* to the *Encyclopédie* before breaking with the impious “sect” of the *philosophes*).
In the entry *Encyclopédie*, Diderot openly contrasts the theocentric vision of the cosmos with an anthropocentric one (*Œuvres*, XIV, pp. 452–53; *Pensées sur l’interprétation de la nature* [1754], ibid., II, p. 53). From Baconian ideas he derives an organic, “formist” conception of nature: the creative “genius” inserts itself, in a vitalistic manner, into this growing cosmos. The “genius” vivifies the blind practice of mechanics, which Diderot values even more radically than d’Alembert does: in the world of technology, *tout est en action et vivant* (see the cited entry and the entry *Art*).
Even in the ethical-religious sphere, the criterion of evaluation must be practical and utilitarian: “the useful circumscribes all.” Virtues deemed “anti-social” are devalued (*Célibat*, *Macération*, *Population*, etc.); so too is pure contemplation (*Malabar*); and morality based on Holy Scripture (*Mosaïque et chrétienne, philosophie*: nature is the philosopher’s book, the Bible the theologian’s). In the entry *Christianisme*, beneath an appearance of respect, religion is reduced to a social function, and it is asserted that “one might sometimes measure the degree of truth of a religion by the degree of utility it affords to states” (*Œuvres*, XIV, pp. 143–45). D’Alembert is more reticent; yet in the *Éléments de philosophie* (VII) he affirms that morality arises with society, and elsewhere he intimates that the universal, useful, and true element of religions consists in their moral truths (*Œuvres*, pp. 224–34, *Opuscules: Sur la véritable religion*, pp. 6–8).
In the article *Genève*, which soon provoked controversies that led d’Alembert to abandon the encyclopedic enterprise in 1758, he extols a “purely Presbyterian” church constitution and a Socinian profession of faith; in the entries *Hiérarchie*, *Société*, *Théocratie*, Diderot goes even further. For the idea of tolerance, the greatest master is Locke.
Great influence was exercised by the naturalism of Diderot upon those abbés, collaborators of the *Encyclopédie*, who might be defined as Catholic illuminists. In the article *Certitude*, de Prades polemicizes against the “scientificism” of the deists and of Diderot himself (referring to the *Pensées philosophiques* of 1746): he arrives at a sort of historicist experimentalism, shared by the abbé Yvon. The latter, however, emphasizes the creative, anti-systematic effort of reason in the genesis of Christian spiritualism, in the articles *Âme* and *Immaterialisme*: the first Christian Fathers showed too much sleepiness for received systems; it was necessary to await Descartes and the moderns to find that *courage de raison* which seeks a path even where it sees no trace. A similar Diderotian motif reappears in the article *Charité*, where an active virtue is extolled against the pure quietist love of Fénelon. Against the “more banal demonism,” however, there rises in the article *Manichéisme* a voice with almost romantic overtones. In the article *Athée*, finally, the fascination exercised upon him by Bayle—whom he nonetheless combats—is evident.
The illuminist ideal of *humanité*, toward which these uncertain Catholics also tend, is nonetheless so rich in religious and Christian residues as to legitimate certain misunderstandings: religious is the expectation of an imminent *révolution... dans l'esprit des hommes et dans le caractère national* (article *Encyclopédie*); the rationalistic myth of original innocence, truth to be “liberated” from historical errors; beneficence and natural sociability that laicize Christian virtues, etc. The natural-law motifs, now entirely secular, do not exclude a religious reformist spirit (article *Droit des gens*, by de Jaucourt, etc.; *Liberté*, by Diderot, where J. A. Turrettini and Fénelon are cited, etc.). For the natural genesis of religion, see the articles *Oeconomie politique*, by Boulanger (q.v.); *Cérémonies*, *Polythéisme*, by Diderot.
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