Genius. Anti-artist. Charlatan. Impostor! Marcel Duchamp has been called all of these. Almost no other artist of the twentieth century has inspired more passion - or greater controversy. Duchamp challenged the very nature of art, striving to redefine it as conceptual rather than as a 'product'; his influence is felt everywhere in today's art world. Always the provocateur, he never ceased his engagement, openly or secretly, in activities and works that transformed traditional modes of art-making....