The Belgian-German artist Carsten Höller is best known for large-scale installations that invite the viewer to participate in or activate them. But his recent exhibition “Videoretrospective with Two Lightmachines” showed another side of his work. The complex and layered show started with Light Wall IV, 2007. LED lamps went rapidly on and off, accompanied by hard stereophonic sounds of clicking, thus evoking a disorienting stroboscopic effect. According to the artist, this disconcerting welcome was intended to put the visitor in a dreamy mood that would allow her to comprehend reality in a