They look completely different, don't they?
Forced Perspective (Shepard's Tables)
Look at the two tabletops. The left one looks long and skinny. The right one looks short and fat. Click the button to see the truth.
Turning 2D into 3D
📐 Size Constancy Failure▼
Roger Shepard showed that our brain cannot help but interpret these 2D shapes as 3D objects (tables).
Because one table is oriented vertically, the brain interprets it as "receding into the distance" (foreshortening). To look that long while receding, the brain assumes the physical object must be VERY long. The other table is oriented horizontally, maximizing its retinal width, so the brain assumes a different physical shape.