Diderot Denys, a French writer and infidel philosopher, was born Oct. 5, 1713, at Langres, in Champagne, where his father was a cutler. He was educated for the Church at the Jesuits' College of Langres; but, declining to take orders, he studied law, soon abandoned that pursuit, and devoted himself to literature. "After ten years of obscure drudgery, he became one of the most famous among those literary and scientific men whose attacks on the established order of things, religious and ecclesiastical as well as political, acted so powerfully in precipitating the French Revolution. Diderot projected the Encyclopedie, ou Dictionnaire Raisonne des Sciences, des Arts et des Metiers, which was designed not merely to supersede the imperfect dictionaries of Chambers and others then in use, but to teach, on every occasion which could admit the teaching, the social and infidel doctrines which were held by the writers. In the course of it, and afterwards, Diderot wrote several didactic treatises, indecent and irreligious novels, and two sentimental comedies; and his published correspondence, especially with Voltaire and Grimm, throws much light on the gloomy picture which French society and morals then presented." He died at Paris July 30, 1784. "The great peculiarity of Diderot was his encyclopaedic knowledge, and his versatility in comprehending a variety of subjects. Less critical than Voltaire, and less philosophical than Rousseau, he exceeded both as a practical teacher. But in unbelief he unhappily advanced farther than either; his temper lacked moral earnestness, and in later life he was an atheist. A
growth of unbelief may be traced in him: at first he was a doubter, next he became a deist, lastly an atheist. In the first stage he only translated English works, and even condemned some of the English deists. His views seem gradually to have altered; probably under the influence of Voltaire's writings, and of the infidel books smuggled into France; and he thenceforth assumed a tone bolder and marked by positive disbelief. In 1746 he wrote his Pensees Philosophiques, intended to be placed in opposition to the Pensees of Pascal. Pascal, by a series of skeptical propositions, had hoped to establish the necessity of revelation. Diderot tried by the same method to show that this revelation must be untrue. The first portion of the propositions bore upon philosophy and natural religion, but at length he came to weaken the proofs for the truth of Christianity, and controverted miracles, and the truth of any system which reposes on miracles; yet even in this work he did not evince the atheism which he subsequently avowed. It was soon after the imprisonment in which he was involved by this book that he projected the plan of the magnificent work, the Encyclopedie, or universal dictionary of human knowledge. Its object, however, was not only literary, but also theological; for it was designed to circulate among all classes new modes of thinking, which should be opposed to all that was traditionary. Voltaire's unbelief was merely destructive; this was reconstructive and systematic. The religion of this great work was deism; the philosophy of it was sensationalist and almost materialist, seeming hardly to allow the existence of anything but mechanical beings. Soul was absorbed in body; the inner world in the outer — a tendency fostered by physics. It was the view of things taken by the scientific mind, and lacks the poetical: and feeling elements of nature — a true type of the cold and mechanical age which produced it. Diderot's atheism is a still further development of his unbelief. It is expressed in few of his writings, and presents no subject of interest to us, save that it seeks to invalidate the arguments for the being of a God, drawn from final causes. It has been well observed that the lesson to be derived from him is that the mechanical view of the world is essentially atheistic; that whosoever will admit no means of discovering God but common logic, cannot find him. Diderot's unbelief may be considered to embody that which resulted from the abuse at once of erudition, physical science, and the sensational theory in metaphysics" (Farrar, Critical History of Free Thought, lect. v). A collection of his principal works was published by his disciple Naigeon, in 15 vols. 8vo, 1798, and reprinted since in 22 vols. 8vo, Paris, 1821, with a life of the author by Naigeon himself, which, however, is rather a dissertation on Diderot's writings and opinions than a real biography. Supplementary to the above edition of Diderot's works are Correspondance philos. et critique de Grimm et Diderot (Paris, 1829, in 15 vols.), and the Memoires, Correspondance, et Ouvrages inedits de Diderot (Paris, 1830, 4 vols). See also Rosenkranz, Diderot's Leben und Werke (1866, 2 vols.); Carlyle, Miscel. Works , vol. iv; Rich, Dictionary of Biography; Engl. Cyclopoedia; Vinet, French Literature; Hoefer, Aouv. Biog. Generale, 14:80 sq.