Denis Diderot was a prominent philosopher, art critic, polymath, and writer of the French Enlightenment, best known today as co-founder and chief editor of the Encyclopédie. Diderot was educated by the Jesuits in Langres and earned a master of arts degree in philosophy in Paris. He considered entering the clergy and studying law. However, by 1734 Diderot had decided to become a writer. Because of his refusal to enter one of the learned professions, he was disowned by his father, and for the next 10 years he lived a Bohemian existence, in near-poverty, dodging the censors. He befriended Jean-Jacques Rousseau, Madame d'Epinay, and other writers and thinkers (philosophes). In 1743, he married Antoinette Champion, daughter of a linen draper, a match his father considered inappropriate; the couple had one surviving child. Diderot had affairs with the writer Madeleine de Puisieux and Sophie Volland; his letters to them contain some of the most vivid insights that historians have into his personality and the daily life of the French philosophes of the period. Diderot was elected to the Académie française, but still had financial troubles, especially when it came time for his daughter Marie-Angelique to marry, and was about to sell his library. Jacob Grimm appealed on his behalf in 1765 to Catherine the Great of Russia, who commissioned an agent in Paris to buy the library; she then requested that Diderot retain the books and act as her librarian with an annual salary that she paid in advance. In 1773, Diderot went to visit the Empress in Saint Petersburg to thank her, and spent some months at court. After his death, his library was deposited at the National Library of Russia. Diderot's last words were said to be, "Le premier pas vers la philosophie, c'est l'incrédulité" ("The first step toward philosophy is incredulity").