What, we wonder, would Peter Simple have had to say about Pierre Pinoncelli, the 77-year-old—what to call him? artist? provocateur? crank?—who at the Centre Pompidou recently took a hammer to the world’s most famous urinal, i.e., Marcel Duchamp’s “Fountain,” an ordinary urinal to you and me but elevated by the alchemy of Dada to the status of art or at least “art.” (Mr. Pinoncelli and the urinal go way back: he had attacked it once before, in 1993.) “I threw … the urinal in their faces as a challenge,” Duchamp said contemptuously after he had abandoned art for chess, “and now they admire [it] for [its] aesthetic beauty.” The French judge who heard the case did not dilate on the beauty of “Fountain,” but, by slapping Mr. Pinoncelli with a suspended jail sentence and a fine of some $260,000 (including a repair bill of $17,000), he did certify its status as a valuable piece of ceramic. Mr. Pinoncelli maintained that by defacing the work, he made it into an original. And why not? Other artists crush a car and call it art. Why not chip a urinal? We suspect that the only thing standing between Mr. Pinoncelli and artistic celebrity is the institution of private property.