Do you see the two shades of green below?
Would you believe that there is actually only one shade of green?

Is the blue side in the front or back of the cube?

See these scrap bits they will look as if they are rotating

Warning dont focus for too long,this might lead to headache or watering of eyes

Look at this picture.
Does it seem to move back and forth?

The square marked A and B are the same shade of gray, yet they appear different.

Published by Edward H. Adelson

The square marked A and B are the same shade of gray, yet they appear different.

By joining the squares marked A and B with two vertical stripes of the same shade of grey, it becomes apparent that both squares are the same.

This painting on the floor looks so real

The cubes appear to be deformed