French philosopher, born at Craon; travelled in Egypt and Syria; wrote an account of his travels in his "Voyage"; was imprisoned during the Reign of Terror; patronized and promoted to honor by Napoleon, and by the Bourbons on their return; his principal work, "Les Ruines, ou Méditations sur les Révolutions des Empires," was an embodiment of 18th-century enlightenment (1757-1820).