Clearly the cat is walking up the stairs because cats love to climb, but eventually he will have to go down again.  The Schröder staircase illusion may be perceived either as a cat climbing up a staircase or going down same staircase because your brain focuses on separate sections of the image and perceives that the stairs are joined together.  German mathematician and physicist Heinrich G. F. Schröder published his optical Illusion staircase in 1858 and this would later evolve into other works done by the Dutch artist M. C. Escher.  Your brain can see the cat going up or down the stairs and this psychological phenomenon is known as the Gestalt Shift, (meaning the way a thing has been “placed,” or “put together”) where your perception switches between different interpretations.  When things are close together, we tend to think that they’re related.  The most famous illustration of this phenomenon…