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(1) The writers of the eighteenth century who edited or contributed articles to the "Encyclopédie". (2) Those among them especially who belonged to the "philosophic" party, joined in the "illumination" movement, and may be grouped together because of a certain community of opinions on philosophical, religious, moral, and social questions.


The "Encyclopédie, ou, Dictionnaire raisonné des sciences, des arts et des métiers, par une société de gens de lettres, mis en ordre et publié par M. Diderot . . . et quant à la partie mathématique par M. d'Alembert . . ." in the complete original edition comprises 35 folio volumes as follows: 17 vols. of text (Paris, 1751-1765); 11 vols. of plates (Paris, 1762-1772); 5 vols. of supplement, i.e., 4 of text and 1 of plates (Amsterdam and Paris, 1776-1777); 2 vols. of analytical index prepared by Pierre Mouchon (Amsterdam and Paris, 1780). In 1745, a French translation of Chambers's "Cyclopædia", prepared by John Mills with the assistance of Gottfried Sellius, was to be published in Paris by the king's printer, Le Breton. After the necessary royal privilege had been obtained, a number of difficulties between Mills and Le Breton caused the failure of the enterprise, and Mills returned to England. Le Breton asked Jean-Paul de Gua, professor in the Collège de France, to assume the editorship and revise the manuscripts. But again misunderstandings and disputes obliged de Gua to resign. Diderot was then called upon to complete the preparation of the manuscripts. At his suggestion, however, it was decided to undertake a more original and more comprehensive work. Diderot's friend, d'Alembert, agreed to edit the mathematical sciences. Diderot (1713-84) had not yet written any original work except the "Pensées philosophiques" (1746), in which the foundations of Christianity are examined and undermined, revelation rejected, and reason proclaimed independent. The Parliament had ordered the book to be burnt. The "Promenade d'un sceptique" was written in 1747, but not published before the author's death. Diderot had also published a translation of Stanyan's "Grecian History" (1743) and an adaptation of Shaftesbury's "Inquiry concerning Virtue and Merit" under the title "Principes de la philosophie, ou Essai sur le mérite et la vertu" (1745). His main recommendation as editor of the new Encyclopédie, however, was the "Dictionnaire universel de médecine" (1746-1748), a translation of Dr. Robert James's "Medical Dictionary". D'Alembert (1717-83) was already famous as a mathematician. At the age of twenty-two he had presented two studies to the Académie des Sciences, "Sur le calcul intégral" (1740). The following year he was elected a member of the Académie. He had acquired a still greater reputation by his "Traité de dynamique" (1743) and the "Mémoire sur la cause générale des vents" (1747), the latter winning for its author the prize offered by the Berlin Academy and membership in that body.

While the articles were being printed Diderot was imprisoned at Vincennes, 29 July, 1749, for his "Lettre sur les aveugles à l'usage de ceux qui voient", or rather for a passage in it which had displeased Madame Dupré de Saint-Maur. After four months his publishers obtained his release; in November, 1750, the Encyclopédie was announced in a prospectus by Diderot, and, in July, 1751, the first volume was published. It opened with a "Discours préliminaire" by d'Alembert, in which the problem of the origin of ideas is solved according to Locke's sensualism, and a classification of sciences is proposed which, except in a few minor points, is that of Bacon. In the prospectus Diderot had already said: "If we succeed in this vast enterprise our principal debt will be to Chancellor Bacon who sketched the plan of a universal dictionary of sciences and arts at a time when there were, so to say, neither sciences nor arts." D'Alembert acknowledged the same indebtedness. Thus, British influence was considerable both in shaping the doctrine of the "Encyclopédie" and in bringing about its publication. The second volume appeared in January, 1752. In consequence of many protests against the spirit of the work, its sale was stopped, and later the arrêt of the King's Council suppressed both volumes as injurious to religion and royal authority (7 February, 1752). Three months later, however, Diderot and d'Alembert were asked to continue the work, a fact which they announce with pride in the preface to the third volume (October, 1753). The following volumes were published without any interruption until after the publication of the seventh volume (1757), when new difficulties arose. In his article on Geneva, d'Alembert had stated that the ministers of that city were Socinians, and praised them for their unbelief. They protested strongly, and this was the occasion for bitter discussions in which Voltaire and Rousseau took a prominent part. The outcome was that d'Alembert, tired of vexations, resigned the editorship. Rousseau also ceased to have anything to do with the Encyclopédie, and thenceforth showed a vehement hostility to it. On the other hand, there were so many denunciations that finally an arrêt of the Council (8 March, 1759) revoked the privilege granted in 1746, and forbade the sale of the volumes already printed and the printing of any future volume. And yet, under the secret protection of Choiseul, Madame de Pompadour, Malesherbes, then director-general of the Librairie, and Sartine, the chief of police, work was resumed almost immediately. The ten remaining volumes were to be published together. After Diderot had corrected the proof-sheets, Le Breton, fearing new vexations, suppressed passages likely to be objectionable and to cause friction with the authorities. Diderot noticed the changes too late to prevent them. The articles were mutilated to an extent which it is now impossible to determine, as all manuscripts and proof-sheets were immediately destroyed. At last, in 1765, volumes VIII-XVII were published, completing the text of the Encyclopédie.

It is not possible to mention here all the contributors (about 160) to the work. Diderot himself wrote 990 articles on almost every subject, philosophical, religious, and moral, but especially on the arts and trades. Great care was taken in the treatment of the mechanical arts. No trouble was spared to obtain minute descriptions of various machines and the means of using them. All this was explained in the text and illustrated in the plates. D'Alembert's articles, with few exceptions, are on the mathematical and physical sciences. From the beginning Rousseau (1712-1778), then known as the author of several musical works and compositions, agreed to write the articles on music. He also wrote the article, "Economie politique". The collaboration of Buffon (1707-88) who had promised to write on "Nature" is announced in the second volume, but it is doubtful if that article, as printed, is from him. Most of the topics in natural history were treated by Daubenton (1716-99). Articles by d'Holbach (1723-89), Marmontel, Bordeu, are announced in the third volume. The fourth introduces Voltaire (1694-1778) as the author of some literary articles, and says of him: "The Encyclopédie, on account of the justice it has rendered and will always continue to render him, was worthy of the interest which he now takes in it." In the "Discours préliminaire", d'Alembert had praised him as occupying "a distinguished place in the very small number of great poets", and extolled him for his qualities as a prose writer. Condorcet, Grimm, Quesnay, Turgot, Necker also contributed articles or memoirs. De Jaucourt furthered the cause of the Encyclopédie not only by his numerous articles and his constant interest, but also by his attitude and reputation. Far from sharing the materialistic and atheistic tendencies of many of his co-workers, he was at the same time friendly to the Encyclopedists and to some of their enemies. Montesquieu at his death (1755) left an unfinished article on Taste (Goût); but his "Lettres persanes" (1721) and "Esprit des lois" (1748) inspired many of the social and political articles in the Encyclopédie.


The expression spirit of the Encyclopédie may at first seem to be a misnomer. In that vast compilation is found the greatest diversity of subjects and even of views on the same subjects. The writers of the articles belong to all professions and to all classes of society. Names of military men, lawyers, physicians, artists, clergymen, scientists, philosophers, theologians, statesmen, etc. appear on the lists of contributors given at the beginning of each volume. The articles are of unequal value; proportion is lacking, each contributor apparently writing as he thinks fits. Verbosity is a prominent defect, and, at times, the authors indulge in endless digressions. Voltaire repeatedly asked for brevity and better method. (See Letters to d'Alembert, esp. in 1756).

The articles seem to have been gathered together from various sources without any preconceived plan, without any unity or sufficient supervision. Under these conditions the spirit of the Encyclopédie might denote merely one special tendency, or one group of tendencies, which, at first manifested along with many others, gradually became important and finally predominant. To some extent it is that, but it is also more than that. The Encyclopédie was not intended only as a great monument to record the progress realized in sciences, arts, civil and religious institutions, industry, commerce, and all other lines of human endeavour; the Encyclopedists purposed moreover to prepare the future and indicate the way to further progress. The Encyclopédie would be a record, but it would also be a standard; not a mere onlooker, but a leader. In fact, appearing as it did in the third quarter of the eighteenth century, it is a mirror in which the events of the whole century are focused.

At the time of the publication of the Encyclopédie, the French Government was, owing to many causes and influences, already considerably weakened, and still weakening. Dissatisfaction and unrest, though not yet well defined, were spreading among the people. Existing institutions and customs, both religious and political, had recently been denounced in several publications. The "philosophers" were favourably received in the salons of the aristocracy. On the other hand, Jansenism, with the endless discussions of which it had been the source or the occasion, and also with the lack of knowledge and looseness of morals among some members of the clergy, had prepared the way for a reaction in the sense of unbelief. There were other causes less direct, perhaps, and more remote, yet influential in bringing about a break with the past. In Descartes one may find unequivocal germs of the neglect, contempt even, of tradition in philosophy, especially when immediate evidence, the idée claire , is made the sole valid criterion of truth. The influence of British philosophers was far from tending to check the growth of rationalism. Nor can we overlook the influence of the famous "Querelle des Anciens et des Modernes", as it is known in the history of French literature. In the last two decades of the seventeenth century it was one of the main centres of attention. To this discussion, which resulted in a victory for those who favoured the "modern", Brunetière traces back three important consequences: first, the meaning of tradition becomes gradually identified with that of superstition ; second, progress is conceived as an emancipation from, and an abjuration of, the past; finally, and this is still more important, education in all its stages consists more and more in derision of the past. True, recent times everywhere offered masterpieces of art, literature, and science. Whatever side we may take in the old quarrel today, and however much less radical and more impartial our views may be, we can at least understand the attitude of those who succeeded the great men of the age of Louis XIV.

Another important factor was scientific progress. After being too frequently confined to idle a priori controversies, science was asserting its rights, and these it soon came to exaggerate, while it failed to recognize the rights of others. Reason gradually freed itself from the superstition of the past and claimed absolute independence. Ancient, or rather Christian, conceptions of God and the world were not even deemed worthy of the serious consideration of a "thinker". Efficient causes alone were recognized, final causes proscribed. In nature science always dealt with immutable laws ; soon the possibility of miracles and revelation was denied, while mysteries were regarded as absurd. Thus, in the place of traditional beliefs, new ideas were introduced, tending to rationalism, materialism, naturalism, and deism. On positive points there was but little agreement; the tendency was primarily negative. It was an opposition to received dogmas and institutions, an effort to establish a new theoretical and practical philosophy on the basis of merely naturalistic principles. Nothing is truer than d'Alembert's statement, in the "Discours préliminaire", that "our century believes itself destined to change all kinds of laws ". Towards the middle of the eighteenth century the representatives of this movement were the "philosophers", and they were about to centralize their efforts in the Encyclopédie. Great prudence was necessary, and it was used. Some men who were known for their conservative opinions were asked to contribute articles, and the Encyclopédie contained some unexceptionable doctrines and moderate views on religious, ethical, and social problems; moreover, the editors themselves and those who shared their views frequently concealed or disguised their true convictions. As Voltaire says, they were in the sad necessity of "printing the contrary of what they believed " (Letter to d'Alembert, 9 October, 1756). More was insinuated than was clearly expressed, and at times a sarcastic remark was used with better effect than a definite statement or argument. When the main article to which one would naturally turn for information contained nothing objectionable, other articles, less likely to attract attention, expressed different and more "philosophic" views. That such was the condition of affairs is attested by a significant passage in a letter of d'Alembert to Voltaire (21 July, 1757). To the latter's criticism of certain articles he replies: "No doubt we have bad articles in theology and metaphysics ; but with theologians for censors, and a privilege, I defy you to make them any better. There are other articles less exposed to the daylight in which all is repaired. Time will enable people to distinguish what we have thought from what we have said." Hence, although the Encyclopédie itself contains many articles in which anti-Christian principles are openly professed, the true, unrestrained encyclopedic spirit was found in the meetings of the "philosophers" and in the salons, where they were looked upon as oracles. Today it is to be found in the later works of the Encyclopedists and chiefly their letters and memoirs. In the impious and cynical d'Alembert, for instance, as known from his correspondence with Voltaire, one would fail to recognize the prudent and reserved d'Alembert of the Encyclopédie. "You were born with the finest and most virile genius", Voltaire wrote to him (4 June, 1769), "but you are free only with your friends, when the doors are closed". This last remark applies also to Diderot and the other Encyclopedists. Their private letters reveal their true spirit and intentions, and prove that the apparent moderation and tolerance shown in their public writings were dictated by fear and not by conviction.

It is difficult to estimate the influence which the Encyclopédie exerted on the events that followed it publication, especially the French Revolution . To a large extent undoubtedly it was not the source, but only the reflection, of the religious and social views of the time. Not the Encyclopédie so much as the Encyclopedists exerted a real influence. Since their spirit was antagonistic to the Church and, in many respects, also to the State, one may ask why its manifestations were not suppressed; why in particular its organ, the Encyclopédie, was allowed to proceed, notwithstanding the warnings of its adversaries and its repeated condemnation by the civil authorities. In a word, what was done to check its influence or to oppose its doctrines? In general, it may be answered that little was done, and, under the circumstances, perhaps little could be done. The defenders of the Faith were not idle; they wrote books and articles in refutation of the "philosophers"; but their voice was not heard, and their scattered efforts were of little avail against the organized forces and the powerful protectors of their adversaries. The Jesuits, the secular clergy, especially Archbishop Christophe de Beaumont, of Paris, and Bishop Le Franc de Pompignan, of Le Puy, who wrote pastorals on the subject, and several other writers and preachers denounced the Encyclopédie. We have seen that they succeeded more than once in having its publication and sale prohibited by the Government. The suspensions were only temporary. The Encyclopedists were under the patronage of high personages at the Court; they were protected especially by Malesherbes, the director of the Librairie, who controlled, among other things, the granting of privileges for new publications and the censuring of books, and by Sartine, the chief of police, on whom depended the enforcement of the laws and ordinances concerning the printing and sale of books. Malesherbes always showed himself the friend of not only of the Encyclopédie, but also of the Encyclopedists. Owing to this friendship, many works were published notwithstanding the official position of the Government. In 1759, after the decision of the council had revoked the privilege formerly granted, it was Malesherbes who warned Diderot that his papers were to be seized the next day. As it was too late to look for a place of safety where they could be taken, Malesherbes had them sent to his own house.

Thus the Government secretly favoured an enterprise which it officially censured, and, under this protection the Encyclopédie was begun and completed. Partly for the same reason, partly also for deeper reasons concerning the religious and civil conditions in France, the efforts to combat the Encyclopédie were not rewarded with much success. Moreau in the "Mémoires pour servir à l'histoire des Cacouacs" (1757), Palissot, in his "Petites lettres sur de grands philosophes" (1757) and in his comedy "Les philosophes" (1760), tried to use the weapons of ridicule and satire which some of the "philosophers", especially Voltaire, wielded with greater skill. Fréron, in the "Année littéraire", was at times sarcastic, and always ready to give and take blows. Constantly at war with the Encyclopedists, he was at a great disadvantage, for they enjoyed Malesherbe's protection, whereas for him the censure was always very severe. Thus he was hardly allowed to write on Voltaire's "Ecossaise" (1760), in which he had been publicly insulted on the stage. The Jansenists, in the "Nouvelles ecclésiastiques", did little more than insult the Encyclopedists. In the "Journal de Trévoux", the Jesuits, and among them especially Berthier (1704-82), who was director of the Journal from 1745 till the suppression of the Society of Jesus , wrote frequent criticisms. But notwithstanding all this opposition the spirit of irreligion was steadily gaining. Too often the criticism was weak, the attack unskillful. In some cases even, the anti-Encyclopedists, instead of harming their opponents, rather contributed to their success by giving them notoriety and affording them an opportunity for using their influence. The Jesuits were expelled from France in 1762; this gave a new victory and a new prestige to the "philosophers". D'Alembert, who wrote "La destruction des Jésuites en France" (1765), looks upon this expulsion as the just punishment of their hostility towards the Encyclopédie. Gradually the people were becoming accustomed to the new spirit, and thus it was that, whereas the first volumes had created a great stir in France, the appearance of the last volumes was scarcely noticed.

Unknown or little known in 1750, the "philosophers" had now won their battle, and were the recognized victors. Their success made them bolder in declaring openly what fear had frequently obliged them to veil in their former works and in the Encyclopédie. These doctrines had also been made more familiar by the publication of several works before the completion of the Encyclopédie, the most important being Diderot's "Pensées sur l'interprétation de la nature" (1754); Helvétius's "De l'esprit" (1758); Rousseau's "Discours sur l'origine et les fondements de l'inégalité parmi les hommes" (1753), "Contrat social" (1762), and "Emile" (1762); Voltaire's "Dictionnaire philosophique" (1765); d'Holbach's "Système de la nature" (1770). Hence, on 8 July, 1765, Voltaire could write to d'Alembert: "They clamour against the philosophers, and are right ; for, if opinion is the ruler of the world, this ruler is governed by the philosophers. You can hardly imagine how their empire is spreading."

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