David Mason at The Hudson Review:
There are at least two Diderots, both controversial, both remarkable Enlightenment figures. The first was a renowned philosophe and atheist associated with Voltaire and Rousseau but often thought their inferior in accomplishment. He was known chiefly as the major author and editor of the Encyclopédie—a revolutionary project of the eighteenth century—as well as a few plays and other works such as Philosophical Thoughts (1746), The Skeptic’s Walk (same year) and Letter on the Blind (1749). He also wrote a brilliantly risqué novel, The Indiscreet Jewels (1748), in which women’s genitalia narrate their experiences. Perhaps this is the figure about whom W. H. Auden wrote, in “Voltaire at Ferney,” “Dear Diderot was dull but did his best.” Auden loved alliteration more than truth in that line. Diderot was anything but dull and did not always do his best. In 1749 he spent four months in prison for his early writings, and that trauma probably shocked him into withholding some of his most significant work from publication.
more here.