194 DIDEROT phic significance of the two essays is in the advance they make towards the principle of Relativity. But what interested the militant philosophers of that day was an episodic application of the principle of relativity to the master-conception of God. What makes the Letter on the Blind interesting at the present moment is its presentation, in a distinct though undigested form, of the modern theory of variability, and of survival by superior adaptation. It is worth noticing, too, as an illustration of the comprehen sive freedom with which Diderot felt his way round any subject that he approached, that in this theoretic essay he suggests the possibility of teaching the blind to read through the sense of touch. If the Letter on the Blind introduced Diderot into the worshipful company of the philosophers, it also introduced him to the penalties of philosophy. His speculation was too hardy for the authorities, and he was thrown into the prison of Vincennes. Here he remained for three months ; then he was released, to enter upon the gigantic undertaking of his life. A certain bookseller had applied to him with a project for the translation into French of Ephraim Chambers s Cyclopaedia. Diderot accepted the proposal, but in his busy and pregnant intelligence the scheme became trans former!. Instead of a mere reproduction of Chambers, he persuaded the bookseller to enter upon a new work, which should collect under one roof all the active writers, all the new ideas, all the new knowledge, that were then moving the cultivated class to its depths, but still were compara tively ineffectual by reason of their dispersion. His enthusiasm infected the publishers ; they collected a sufficient capital for a vaster enterprise than they had at first planned ; D Alembert was persuaded to become Diderot s colleague ; the requisite permission was procured from the Government ; in 1750 an elaborate prospectus announced the project to a delighted public ; and in 1751 the first volume was given to the world. The last of the letter-press was issued in 1765, but it was 1772 before the subscribers received the final volumes of the plates. These twenty years were to Diderot years not merely of incessant drudgery, but of harassing persecution, of sufferings from the cabals of enemies,and of injuryfrom the desertion of friends. The ecclesiastical party detested the Encyclopaedia, in which they saw a rising stronghold for their philosophic enemies. By 1757 they could endure the sight no longer. The sub scribers had grown from 2000 to 4000, and this was a right measure of the growth of the work in popular influence and power. To any one who turns over the pages of these redoubtable volumes now, it seems surprising that their doctrines should have stirred such portentous alarm. There is no atheism, no overt attack on any of the cardinal mysteries of the faith, no direct denunciation even of the notorious abuses of the church. Yet we feel that the atmosphere of the book may well have been displeasing to authorities who had not yet learnt to encounter the modern spirit on equal terms. The Encyclopaedia takes for granted the justice of religious tolerance and speculative freedom. It asserts in distinct tones the democratic doctrine that it is the common people in a nation whose lot ought to be the main concern of the nation s government. From beginning to end it is one unbroken process of exaltation of scientific knowledge on the one hand, and pacific industry on the other. All these things were odious to the old governing classes of France; theirspiritwasabsolutist, ecclesiastical, and military. Perhaps the most alarming thought of all was the current belief that the Encyclopaedia was the work of an organized band of conspirators against society, and that a pestilent doctrine was now made truly formidable by the confedera tion of its preachers into an open league. When the seventh volume appeared, it contained an article on " Geneva," written by D Alembert. The writer contrived a panegyric on the pastors of Geneva, of which every word was a stinging reproach to the abbes and prelates of Versailles. At the same moment Helve tius s book, L Esprit, appeared, and gave a still more profound, and, let us add, a more reasonable shock to the ecclesiastical party. Authority could brook no more, and in 1759 the Encyclopaedia was formally suppressed. The decree, however, did not arrest the continuance of the work. The connivance of the authorities at the breach of their own official orders was common in those times of distracted government. The work went on, but with its difficulties increased by the necessity of being clandestine. And a worse thing than troublesome interference by the police now befell Diderot. D Alembert, wearied of shifts and indignities, withdrew from the enterprise. Other powerful colleagues, Turgot among them, declined to con tribute further to a book which had acquired an evil fame. Diderot was left to bring the task to an end as he best could. For seven years he laboured like a slave at the oar. He wrote several hundred articles, some of them very slight, but many of them most laborious, comprehensive, and ample. He wore out his eyesight in correcting proofs, and he wearied his soul in bringing the manuscript of less com petent contributors into decent shape. He spent his day.^ in the workshops, mastering the processes of manufactures, and his nights in reproducing on paper what hs had learnt during the day. And he was incessantly harassed all the time by alarms of a descent from the police. At the last moment, when his immense- work was just drawing to an end, he encountered one last and crowning mortification : he discovered that the bookseller, fearing the displeasure of the Government, had struck out from the proof sheets, after they had left Diderot s hands, all passages that he chose to think too hardy. The monument to which Diderot had given the labour of twenty long and oppressive years was irreparably mutilated and defaced. It is calculated that the average annual salary received by Diderot for his share in the Encyclopaedia was about 1 20 sterling. " And then to think," said Voltaire, " that, an army contractor makes 800 in a day ! " Although the Encyclopaedia was Diderot s monumental work, he is the author of a shower of dispersed pieces that sowed nearly every field of intellectual interest with new and fruitful ideas. We find no masterpiece, but only thoughts for masterpieces ; no creation, but a criticism witl the quality to inspire and direct creation. He wrote plays le Fils Naturel and le Pere de Famille-^and they are very insipid performances in the sentimental vein. But he accompanied them by essays on dramatic poetry, including especially the Paradoxe sur le Comadien, in which he announced the principles of a new drama, the serious, domestic, bourgeois drama of real life, in opposition to the stilted conventions of the classic French stage. It was Diderot s lessons and example that gave a decisive bias to the dramatic taste of Lessing, whose plays, and his Ilambwyiscke Dramaturgic, (1768), mark so important an epoch in the history of the modern theatre. In the pictorial art, Diderot s criticisms are no less rich, fertile, and wide in their ideas. His article on "Beauty" in the Encyclopaedia shows that he had mastered and passed beyond the metaphysical theories on the subject, and the Essay on Painting was justly described by Goethe, who thought it worth translating, as " a magnificent work, which speaks even more helpfully to the poet than to the painter, though to the painter too it is as a blazing torch." Diderot s most intimate friend was Grimm, one of the conspicuous figures of the philosophic body. Grimm wrote news-letters to various high personages in Germany,
reporting what was going on in the world of art and