Using two diagonal tubes in a wooden frame, Johannes Langkamp shapes two triangles into a square that gets bigger and then smaller again. Unlike an illusion, you can see exactly how he does this; the corners of the fabric are raised by wires around the framework that are driven via pulleys by a reduction motor. You can marvel at the illusion in front of your eyes or imagine the artist’s pleasure of making and discovering all those different parts and details of the sculptural animation.