Cafe wall illusion
As you move the slider, you may think that the above object is skewing the lines, and bending them as the black blocks pass. Funny thing is, that it is your brain that is doing it, not the object. If you don’t believe me, try changing the colors, and see what effect it has.
For a very clear and detailed explaination of what is going on, follow the link below.
brainconnection.com
via re
