The Shepard’s tables illusion was identified by the cognitive scientist Roger Shepard. The illusion shows images of two tables, where one table seems longer and thinner, even though it is actually identical to the other. The receding edges of the tables are seen as if stretched in depth, and due to the phenomenon of size-constancy, objects can appear wider when seen further away. This can be seen with the Shepard’s tables, in that the oblique edges of the tables seem to become further apart with distance.

See more visual and auditory illusions.