The silence of Marcel Duchamp is overrated (Das Schweigen von Marcel Duchamp wird überbewertet) was an action performed by Beuys on 11 December 1964. It was transmitted on German live television from the studio of channel ZDF in Düsseldorf, Germany. Parallel to Beuys, his Fluxus co-artists Bazon Brock and Wolf Vostell also performed actions in the studio. The performance was not recorded, only a photo series by Manfred Tischer exists which was later the subject of a copyright lawsuit.

The performance began with Beuys bringing a felt blanket into the room, where a wooden shack had been placed. He then took margarine from several boxes and proceeded to create a "fat corner" (Fettecke) in the shack. He also put some fat on the felt blanket and rang a bell. He then wrote the letters DAS SCHWEIGEN VON MARCEL DUCHAMP WIRD ÜBERBEWERTET on a wooden panel, using chocolate paint and attaching additional chocolate bars. Finally, Beuys attached fat to the ends of a cane.

The action must be seen in the context of the Fluxus debate over Duchamp's concept of art. With his "ready-mades", Duchamp had questioned the traditional idea of what constitutes art. In later years, Duchamp had given up art and concentrated on chess and writing. Beuys' performance critises Duchamp for his silence and posits a counter-stance, effectively arguing that the artist must remain active and activist despite the "emptiness" of art as a concept that Duchamp had exposed.