"The back story of twentieth-century art concerns the changing intellectual, economic, and technological setting that would cause the art of the past century to be fundamentally different from that of all earlier times. The single most important change involved the structure of the market for...

"Words have appeared in visual art since classical times, but until the modern era their use was generally restricted to a few specific functions. In the early twentieth century, the Cubists Braque and Picasso began using words in their paintings and collages in entirely new ways, and their...