"Readymades" were found objects which Duchamp chose and presented as art. In 1913, Duchamp installed a Bicycle Wheel in his studio. However, the idea of Readymades did not fully develop until 1915. The idea was to question the very notion of Art, and the adoration of art, which Duchamp found "unnecessary".

"My idea was to choose an object that wouldn't attract me, either by its beauty or by its ugliness. To find a point of indifference in my looking at it, you see."

Bottle Rack (1914), a bottle drying rack signed by Duchamp, is considered to be the first "pure" readymade. Prelude to a Broken Arm (1915), a snow shovel, also called In Advance of the Broken Arm, followed soon after. His Fountain, a urinal signed with the pseudonym "R. Mutt", shocked the art world in 1917. Fountain was selected in 2004 as "the most influential artwork of the 20th century" by 500 renowned artists and historians.

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