Performance artist’s aggressive art historian shouts at visitors and insults curators – and his tours are sold out Performance artist’s aggressive art historian shouts at visitors and insults curators – and his tours are sold out O n a recent autumn evening in Düsseldorf’s Kunstpalast museum, the guide Joseph Langelinck paused next to a Renaissance sculpture of a man with a wooden club and challenged his flock of 18 visitors to name the mythical hero depicted. “Hercules?” a woman in the front