 Because of his public leadership of the philosophe party in eighteenth-century France, Voltaire stands today as the iconic example of the French Enlightenment philosopher. Denis Diderot (1713–1784) is often seen as Voltaire’s second in that role since it was around both men that the Enlightenment philosophes rallied as a movement after 1750. The epochal project, which Diderot jointly pursued with Jean le Rond D’Alembert, to “change the common way of thinking” through a comprehensive Encyclopedia, or Reasoned Dictionary of the Arts, Sciences, and Trades provided the emergent philosophe movement with the cause around which they would coalesce. Diderot also fought vigorously with Voltaire on behalf of the Encyclopédie project and its principles, becoming as a result a public leader of the Enlightenment philosophical party in France alongside Voltaire. He also worked, like Voltaire, as a writer and critical intellectual who willingly positioned himself against the grain of established authority, and one who used philosophy as a vehicle for political and social activism. Yet Diderot’s philosophy pursued many more agendas and dimensions than Voltaire’s. He also left behind a corpus of philosophical writings that marks him out as arguably the most sophisticated of all the Enlightenment philosophes, and as one of the great philosophical thinkers of the eighteenth-century.