Most artworks are labelled Don’t Touch; most sculptures, when touched, don’t react. Chiu Chao-Tsai’s guiding rule is to break both rules. He specialises in interactive sculptures, which not only invite viewers to handle them but move in response. The effect is psychological as well as aesthetic: the viewer becomes a player and a manipulator, a child with a new toy and an adult intent on control. It is also social: engaging with the works initiates a physical dialogue in which the viewer talks with his fingers and the sculpture answers in metaphors. Each black structure in the World of Fatigue series (2009) can be wound up like a mechanical toy, but instead of marching or spinning or flying, it merely flops as if exhausted. The “ghostly, blurred” shadows cast by the gallery lights suggest a dream state, Chiu Chao-Tsai says. But when the key is re-turned to “wake” the work, “it promptly falls asleep again”.