The Philosophers of the EnlightenmentThis painting shows the French philosopher Voltaire with a group of intellectual luminaries at the summer palace of the Prussian king Frederick II. Such literary gatherings, sometimes called salons, were places of lively conversation among mostly male participants and came to be seen as emblematic of the European Enlightenment.(Painting by Adolph Menzel [1815–1905], 1850/© akg-