"What is the significance of viewer participation in your work? It has to do with kinetic art. Kinetic art has very much to do with the interaction between spectator and art. In the second half of the ’50s, this became a big international movement. When I moved from painting to connections within media, this came through in the first work, which was an exhibition of found cardboard pieces. It was a turning point for me. The world itself, the industrial fabricated world, could stand for the man-made world of art."