William M. Perthes is the Bernard C. Watson Director of Adult Education at the Barnes Foundation. William is an art historian whose scholarship focuses on Modernism, particularly in the United States, with a special concentration on the Abstract Expressionist painter Robert Motherwell.

These lectures will look closely at American painting of the 20th century, a period that saw New York supplant Paris as the center of the global art market. Together the group will explore paintings by artists from the Ashcan School to Abstract Expressionism and Andy Warhol to Kehinde Wiley.