Marcel Duchamp (28 July 1887 – 2 October 1968; French pronunciation: [maʁsɛl dyˈʃɑ̃]) was a French artist whose work is most often associated with the Dadaist and Surrealist movements. Duchamp's output influenced the development of post-World War I Western art. He advised modern art collectors, such as Peggy Guggenheim and other prominent figures, thereby helping to shape the tastes of Western art during this period. A playful man, Duchamp challenged conventional thought about artistic processes and art marketing, not so much by writing, but through subversive actions such as dubbing a urinal art and naming it Fountain. He produced relatively few artworks, while moving quickly through the avant-garde circles of his time. The creative act is not performed by the artist alone; the spectator brings the work in contact with the external world by deciphering and interpreting its inner qualifications and thus adds his contribution to the creative act.