Sandro del Prete
New Figure: The Impossible Ring Disk with Two Sides and Two Edges
![New Figure: The Impossible Ring Disk with Two Sides and Two Edges](../../../../images/art/delprete/the-master-of-illusions/149.jpg)
This new shape, though different from the one above it, has the same qualities as
the other figures. An object would travel a full cycle along its path in a clockwise
direction - and once again in a counterclockwise direction - without passing over
the other objects on the ring disk. The object moves toward the observer or in the
opposite direction, away from the observer, but this to-and-fro motion illusory.
It relies on a temporal element, and could therefore be called four-dimensional.