http://en.wikipedia.org/wiki/Impossible_colors
Go to the picture in that article and look at one of the left squares for a full minute, then look at the corresponding middle square. You'll see some shades that cannot be observed under normal viewing conditions (like a shade of red that is brighter than white) but which you can trick your brain into seeing.
Science!
Go to the picture in that article and look at one of the left squares for a full minute, then look at the corresponding middle square. You'll see some shades that cannot be observed under normal viewing conditions (like a shade of red that is brighter than white) but which you can trick your brain into seeing.
Science!