Christo and Jeanne-Claude are pressing upon us a remarkably fanciful vision. But because their art is public, theirs is not just a triumph of the imagination over the dull, dreary world. It is also a triumph of the artist's will over everyone else's will, which makes Christo and Jeanne-Claude direct heirs of Marcel Duchamp. Duchamp's famous exhibition of a urinal declared that anything could be art if he said it was, and after that, certain artists began substituting their will for their creations. From Dada to performance art, the art world has experienced one assault after another on the idea that the work of art is sacred, or "great." This was also an assault on commercial aspect of art. Since no one could point to a thing and say, "This is art," there was nothing to sell. Artists had eluded, defeated the market, which requires a concrete commodity, and then assigns it a price. Or so they thought.