CÉZANNE'S OEUVRE is littered with paintings in various states of incompletion, and what glorious litter it is. By the time of his death in 1906, the most important color on his palette was bare canvas or (in the watercolors) bare paper, an unmark that made the marks around it shiver into life.

With Cézanne “a form exists only by virtue of the neighboring forms,” R.P. Rivière and J.F. Schnerb noted in 1907. Corollary: A blank can be a form. This demonstration of the equal semiotic rights of unworked, unmarked areas made everything possible in modern art, from Pollock's use of bare canvas to Cage's

FIRST YOU WERE PLUNGED into sudden darkness and could see nothing. Then you began to make out the gallery's high-ceilinged industrial space. It had been turned into a cavern filled with the penetrating near-roar of electronically amplified breathing, a hum like that of a film projector, interrupted by occasional attempts at speaking. At opposite comers of this sound chamber, two hanging projection screens leaned toward each other: Godforsaken Hole/Free Hand, 1999. One of the black-and-white video projections showed a disembodied hand groping in the void, motioning in front of the camera as if