Before going further into the general contents of the Encyclopædia, we shall briefly describe the extraordinary succession of obstacles and embarrassments against which its intrepid conductor was compelled to fight his way. The project was fully conceived and its details worked out between 1745 and 1748. The Encyclopedia was announced in 1750, in a Prospectus of which Diderot was the author. At length in 1751 the first volume of the work itself was given to the public, followed by the second in January 1752. The clerical party at once discerned what tremendous fortifications, with how deadly an armament, were rising up in face of their camp. The Jesuits had always been jealous of an enterprise in which they had not been invited to take a part. They had expected at least to have the control of the articles on theology. They now were bent on taking the work into their own hands, and orthodoxy hastily set all the machinery of its ally, authority, in vigorous motion.

The first attack was indirect. An abbé de Prades sustained a certain thesis in an official exercise at the Sorbonne, and Diderot was suspected, without good reason, of being its true author. An examination of its propositions was ordered. It was pronounced pernicious, dangerous, and tending to deism, chiefly on account of some too suggestive comparisons between the miraculous healings in the New Testament, and those ascribed in the more ancient legend to Æsculapius. Other grounds of vehement objection were found in the writer's maintenance of the Lockian theory of the origin of our ideas. To deny the innateness of ideas was roundly asserted to be materialism and atheism. The abbé de Prades was condemned, and deprived of his license (Jan 27, 1752). As he was known to be a friend of Diderot, and was suspected of being the writer of articles on theology in the Encyclopædia, the design of the Jesuit cabal in ruining De Prades was to discredit the new undertaking, and to induce the government to prohibit it. Their next step was to procure a pastoral from the archbishop of Paris. This document not only condemned the heretical propositions of De Prades, but referred in sombre terms to unnamed works teeming with error and impiety. Every one understood the reference, and among its effects was an extension of the vogue and notoriety of the Encyclopædia.[128] The Jesuits were not allowed to retain a monopoly of persecuting zeal, and the Jansenists refused to be left behind in the race of hypocritical intrigue. The bishop of Auxerre, who belonged to this party, followed his brother prelate of Paris in a more direct attack, in which he included not only the Encyclopædia, but Montesquieu and Buffon. De Prades took to flight. D'Alembert commended him to Voltaire, then at Berlin. The king was absent, but Voltaire gave royal protection to the fugitive until Frederick's return. De Prades was then at once taken into favour and appointed reader to the king. He proved but a poor martyr, however, for he afterwards retracted his heresies, got a benefice, and was put into prison by Frederick for giving information to his French countrymen during the Seven Years' War.[129] Unfortunately neither orthodoxy nor heterodoxy has any exclusive patent for monopoly of rascals.

Meanwhile Diderot wrote on his behalf an energetic and dignified reply to the aggressive pastoral. This apology is not such a masterpiece of eloquence as the magnificent letter addressed by Rousseau ten years later to the archbishop of Paris, after the pastoral against Emilius. But Diderot's vindication of De Prades is firm, moderate, and closely argumentative. The piece is worth turning to in our own day, when great dignitaries of the churches too often show the same ignorance, the same temerity, and the same reckless want of charity, as the bishop of Auxerre showed a hundred and twenty years ago. They resort to the very same fallacies by way of shield against scientific truths or philosophical speculations that happen not to be easily reconcilable with their official opinions. "I know nothing so indecent," says Diderot, "and nothing so injurious to religion as these vague declamations of theologians against reason. One would suppose, to hear them, that men could only enter into the bosom of Christianity as a herd of cattle enter into a stable; and that we must renounce our common sense either to embrace our religion or to remain in it ...Such principles as yours are made to frighten small souls; everything alarms them, because they perceive clearly the consequences of nothing; they set up connections among things which have nothing to do with one another; they spy danger in any method of arguing which is strange to them; they float at hazard between truths and prejudices which they never distinguish, and to which they are equally attached; and all their life is passed in crying out either miracle or impiety." In an eloquent peroration, which is not more eloquent than it is instructive, De Prades is made to turn round on his Jansenist censor, and reproach him with the disturbance with which the intestine rivalries of Jansenist and Jesuit had afflicted the faithful. "It is the abominable testimony of your convulsions," he cries, "that has overthrown the testimony of miracles. It is the fatuous audacity with which your fanatics have confronted persecution, that has annihilated the evidence of the martyrs. It is your declamations against sovereign pontiffs, against bishops, against all the orders of the ecclesiastical hierarchy, that have covered priest, altar, and creed with opprobrium. If the pope, the bishops, the priests, the simple faithful, the whole church, if its mysteries, its sacraments, its temples, its ceremonies, have fallen into contempt, yours, yours, is the handiwork."[130]

Bourdaloue more than half a century before had taunted the free-thinkers of his day with falseness and inconsistency in taking sides with the Jansenists, whose superstitions they notoriously held in open contempt. The motive for the alliance was tolerably obvious. The Jansenists, apart from their theology, were above all else the representatives of opposition to authority. It was for this that Lewis XIV. counted them worse than atheists. The Jesuits, it has been well said in keeping down their enemies by force, became the partisans of absolute government, and upheld it on every occasion. The Jansenists, after they had been crushed by violence, began to feel to what excesses power might be brought. From being speculative enemies to freedom as a theory, they became, through the education of persecution, the partisans of freedom in practice. The quarrel of Molinists and Jansenists, from a question of theology, grew into a question of human liberty.[131]

Circumstances had now changed. The free-thinkers were becoming strong enough to represent opposition to authority on their own principles and in their own persons. Diderot's vigorous remonstrance with the bishop of Auxerre incidentally marks for us the definite rupture of philosophic sympathy for the Jansenist champions. "It is your disputatiousness," he said, "which within the last forty years has made far more unbelievers than all the productions of philosophy." As we cannot too clearly realise, it was the flagrant social incompetence of the church which brought what they called Philosophy, that is to say Liberalism, into vogue and power. Locke's Essay had been translated in 1700, but it had made no mark, and as late as 1725 the first edition of the translation remained unsold. It was the weakness and unsightly decrepitude of the ecclesiastics which opened the way for the thinkers.

This victory, however, was not yet. Diderot had still a dismal wilderness to traverse. He was not without secret friends even in the camp of his enemies.

After his reply to Peré Berthier's attack on the Prospectus, he received an anonymous letter to the effect that if he wished to avenge himself on the Jesuits, there were both important documents and money at his command. Diderot replied that he was in no want of money, and that he had no time to spare for Jesuit documents.[132] He trusted to reason. Neither reason nor eloquence availed against the credit at court of the ecclesiastical cabal. The sale of the second volume of the Encyclopædia was stopped by orders which Malesherbes was reluctantly compelled to issue. A decree of the king's council (Feb. 7, 1752) suppressed both volumes, as containing maxims hostile to the royal authority and to religion. The publishers were forbidden to reprint them, and the booksellers were forbidden to deliver any copies that might still be in hand. The decree, however, contained no prohibition of the continuance of the work. It was probably not meant to do anything more serious than to pacify the Jesuits, and lend an apparent justification to the officious pastorals of the great prelates. Some even thought that the aim of the government was to forestall severer proceedings on the part of the parliament of lawyers;[133] for corporations of lawyers have seldom been less bigoted or obstructive than corporations of churchmen. Nor were lawyers and priests the only foes. Even the base and despicable jealousies of booksellers counted for something in the storm.[134]

A curious triumph awaited the harassed Diderot.

He was compelled, under pain of a second incarceration, to hand over to the authorities all the papers, proof-sheets, and plates in his possession. The Jesuit cabal supposed that if they could obtain the materials for the future volumes, they could easily arrange and manipulate them to suit their own purposes. Their ignorance and presumption were speedily confounded. In taking Diderot's papers, they had forgotten, as Grimm says, to take his head and his genius: they had forgotten to ask him for a key to articles which, so far from understanding, they with some confusion vainly strove even to decipher. The government was obliged (May 1752) to appeal to Diderot and D'Alembert to resume a work for which their enemies had thus proved themselves incompetent. Yet, by one of the meannesses of decaying authority, the decree of three months before was left suspended over their heads.[135]

The third volume of the Encyclopædia appeared in the autumn of 1753. D'Alembert prefixed an introduction, vindicating himself and his colleague with a manliness, a sincerity, a gravity, a fire, that are admirable and touching. "What," he concluded, "can malignity henceforth devise against two men of letters, trained long since by their meditations to fear neither injustice nor poverty; who having learnt by a long and mournful experience, not to despise, but to mistrust and dread men, have the courage to love them, and the prudence to flee them?... After having been the stormy and painful occupation of the most precious years of our life, this work will perhaps be the solace of its close. May it, when both we and our enemies alike have ceased to exist, be a durable monument of the good intention of the one, and the injustice of the other.... Let us remember the fable of Bocalina: 'A traveller was disturbed by the importunate chirrupings of the grasshoppers; he would fain have slain them every one, but only got belated and missed his way; he need only have fared peacefully on his road, and the grasshoppers would have died of themselves before the end of a week.'"[136] A volume was now produced in each year, until the autumn of 1757 and the issue of the seventh volume. This brought the work down to Gyromancy and Gythiuin. Then there arose storms and divisions which marked a memorable epoch alike in the history of the book, in the life of Diderot and others, and in the thought of the century. The progress of the work in popularity during the five years between 1752 and 1757 had been steady and unbroken. The original subscribers were barely two thousand. When the fourth volume appeared, there were three thousand. The seventh volume found nearly a thousand more.[137] Such prodigious success wrought the chagrin of the party of superstition to fever heat. As each annual volume came from the press and found a wider circle of readers than its predecessor, their malice and irritation waxed a degree more intense. They scattered malignant rumours abroad; they showered pamphlets; no imputation was too odious or too ridiculous for them. Diderot, D'Alembert, Voltaire, Rousseau, Buffon, were declared to have organised a league of writers, with the deliberate purpose of attacking the public tranquillity and overthrowing society. They were denounced as heads of a formal conspiracy, a clandestine association, a midnight band, united in a horrible community of pestilent opinions and sombre interests.