In 1793, France's revolutionary government decreed that the Louvre Palace, a much-remodeled Parisian fortress, should serve as a museum to house and exhibit the nation's 537 greatest available works of art-mainly stuff ripped from the clutches of kings and clergy on their way out of power and up the blood-slicked steps to headlessness. Circa that same year, also in Paris, an aging portrait painter named Joseph Ducreux completed the 18th-century equivalent of a charmingly douchey Facebook profile picture, Portrait de l'artiste sous les traits d'un moqueur. The piece would later become part of the Musée du Louvre's vaunted collection… and so much more.