From Picasso's Cubism and Duchamp's readymades to Warhol's silkscreens and Smithson's earthworks, the art of the twentieth century broke completely with earlier artistic traditions. A basic change in the market for advanced art produced a heightened demand for innovation, and young conceptual innovators - from Picasso and Duchamp to Rauschenberg and Warhol to Cindy Sherman and Damien Hirst - responded not only by creating dozens of new forms of art, but also by behaving in ways that would have been incomprehensible to their predecessors.