The works of Diderot are numerous, and many of them were not pub lished till after his death. Among those published in his lifetime are Lettres sur lee Sourda et Muets, 1751; 'Pensdes sue 1'Interpretation de Is Nature,' 1754 ; Code de la Nature,' 1765. The principal faults of his didactic compositions are obscurity in the ideas, and a declamatory style. Among his tales, 'Jacques le Fatalists' and 'Le Neveu de Rameau: a posthumous publication, are still popular. 'Lee Bijoux Indis crete,' are a series of obscene stories, which he sold to a publisher, and gave the money to his mistress, Madame do Puisieux. He afterwards formed a connection with Mdlle. Voland, it seems, which lasted till his death. His letters to her form the principal part of the ‘M6moirea, Correapondance, et Ouvrages In&Ilia de Diderot,' published in 1831, 4 vole. 8vo. Diderot's notions on the sexual connection may be seen in the article Marriage,' in the Dictionnaire Encyclop6clique,' as well as in several of his Ouvragea In6clita.' He professed a strict sense of honour, and was generous and kind, though hasty, touchy, and sus picious. An estimate of his character may be formed not from the reports of his admirers or enemies, and there were many of both, but from his own works, and especially his correspondence, and also from a well-written and apparently unsophisticated memoir of his life by his daughter, Madame de Vanden], which is printed at the head of the unedited correspondence above mentioned. A collection of he principal works was published by his disciple Naigeon, in-15 vole„ 8vo, 1798, and reprinted since in 22 vole., 8vo, Paris, 1821, with a life of the author by Naigeon himself, which however is rather a disserta tion on Diderot's writings and opinions thou a real biography. His last work, a life of Seneca, of which he published a second edition enlarged, in 2 vols., under the title of Essai our les Regnea de Claude et de Wren; is considered by some one of his best compositions. It has been said of him that there are many good passages iu all his works, though he never wrote a single'entirely good work. Marmontel,
Carat, and others of his contemporaries preferred his conversation greatly to his writings.
Diderot had not grown rich by his literary labours ; he was getting old, and he thought of selling his library. Catharine of Russia hearing of his intention, purchased it at its full value, and moreover settled upon him a handsome pension as librarian to keep it for her, of which pension she paid him fifty years in advauce in ready money. Full of gratitude, Diderot resolved to go and thank his benefactress in person. He went first to Holland, where he spent some months, and thence to St. Petersburg. He was delighted with his reception by the empress, and wrote to Mdlle. Voland that "while in a country called the land of freemen he felt as a slave ; but now in a country called the country of slaves, he felt like a freeman." (' Correspond ence IntSdite,' vol. iii., lettre 138.) After a short stay at St. Peters burg, he returned to Paris, where the empress hired a splendid suite of apartments for him in the Rue Richelieu. "Ho enjoyed his new lodgings only twelve days : be was delighted with them ; having always lodged in a garret, he thought himself in a palace. But his body became weaker every day, although his head was not at all affected, and he was quite conscious that his end was approaching. The evening before his death he conversed with his friends upon philosophy, and the various means of attaining it. The first step towards philosophy,' said he, 'is incredulity.' This remark is the last which I heard him make." — (' Memoir of Diderot,' by hia daughter)—and it was a very characteristic one. Next day, 30th of July 1784, he got up, sat down to dinner with his wife, and after wards expired without a struggle. Diderot was one of the principal members of the Holbach coterie, and the leader of that knot of literary sceptics known in the last century by the name of Eucyclopddistes. There are many particulars concerning Diderot in his friend Grimm's 'Correspondence Litt6raire,' Paris, 1812.