Appropriation is indeed the first stage of postproduction; the issue is no longer to fabricate an object, but to choose one among those that exist and to use or modify these according to a specific intention. Marcel Broodthaers said that “since Duchamp, the artist is the author of a definition” which is substituted for that of the objects he or she has chosen. […] If the process of appropriation has its roots in history, its narrative here will begin with the readymade, which represents its first conceptualized manifestation, considered in relation to the history of art. When Duchamp exhibits a manufactured object (a bottle rack, a urinal, a snow shovel) as a work of the mind, he shifts the problematic of the “creative process” emphasizing the artist’s gaze brought to bare on an object instead of manual skill. He accesses that the act of choosing is enough to establish the artistic process, just as the act of fabricating, painting or sculpting does; to give a new idea to an object is already production. Duchamp thereby completes the definition of the term creation: to create is to insert an object into a new scenario, to consider it a character in a narrative. (25)
Bourriaud, Nicolas. Postproduction. New York, NY: Lukas & Sternberg, 2002.
via