Geneva! Place du Rhône square, we can see a NON metamorphosing into a OUI on a large sky background, even though this small square is nestled between buildings. In order to successfully display this vision against the background of the sky and thus avoiding the buildings and signs of this square, Markus Raetz had to reduce from 90° to 66° the angle between the axis of vision of NON and that of OUI. If 90° is the right angle to hide one image from the other, wouldn't the OUI and NON images have a chance of appearing simultaneously at 66°? Would it then be a form related to the Duck-Rabbit? Precisely, not far from the famous Raetz' Rabbit, I found another one, on the famous Geneva altar painted by Witz!