Peter Schjeldahl recaps performance artist Chris Burden’s career for The New Yorker. I don’t know how long the link will stay alive, but check out this pithy definition:
In pragmatic terms, art is a privileged zone of gratuitous activity, with boundaries maintained by the agreement of the vested authorities. Artists of the Duchampian sort delighted in effacing the boundaries, which, with increasingly avid complicity on the authorities’ part, kept being redrawn to corral the effacements. It was a silly game, in the end. Ultimate limits were discovered, most pointedly by Burden, whose influence on conceptual and installational artists, to this day, is immeasurable.