If your eyes follow the movement of the rotating pink dot,you will only see one color, pink.
If you stare at the black + in the center, the moving dot turns to green.
Now concentrate on the black + in the center of the picture.
After a short periode of time, all the pink dots will slowly disappear,
and you only see a green dot rotating if you're lucky!
It's amazing how our brain works. There really is no green dot,
and the pink ones really don't disappear.
This should be proof enough, we don't always see what we think to see.