Reversing Staircase Illusion
Our perceptual organization process continues after providing a result. Continue viewing the Reversing Staircase Illusion and you will see it flip into a second staircase.
M.C. Escher used complex variations on this illusion to achieve some wonderful effects like showing representations of people walking in opposite directions, both descending. He also joined staircases into an appearance of infinite ascent/descent.
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