The pioneering conceptual artist John Baldessari (b. 1931) began his career as a painter in the 1950s, but in the subsequent decades he expanded his practice in a new and groundbreaking direction by juxtaposing texts with found photography or appropr...

Robert Rauschenberg (b. 1925) began to investigate the boundaries between painting and sculpture in the 1950s, working with a variety of found objects in his Combine paintings and freestanding Combines. Later, in his "Cardboard" series (1971-72), he...