Over the last 50 years, Claes Oldenburg has created an art of parody and humor by radically altering the scale of and materials associated with everyday objects. His early work in the 1960s took the form of brightly painted plaster reliefs and sculptures of foodstuffs and other commercial products. Later the canvas props that Oldenburg had sewn for earlier performancebased events led to large-scale soft sculptures. By the mid-1960s, the artist turned his attention to drawings and proposals for outdoor monuments—some imaginary, some real. A 45-foot-tall version of Clothespin is installed near City Hall in Philadelphia.