we don't always see what we think we see
If your eyes follow the movement of the rotating pink dot, you will only see one color, pink.
However. 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 period, all the pink dots will slowly disappear, and you will only see a green dot rotating.
http://webmail.att.net/wmc/v/wm/4485939A00058D620000646621603759649D0E960E04D20E?cmd=GetImg&no=20&uid=130529&sid=c0&name=001601c68719$db258840$84809e18@ownercgpkrz1hx
However. if you stare at the black "+" in the center, the moving dot turns to green.
Now, concentrate on the black "+" in the center of the picture. After a short period, all the pink dots will slowly disappear, and you will only see a green dot rotating.
http://webmail.att.net/wmc/v/wm/4485939A00058D620000646621603759649D0E960E04D20E?cmd=GetImg&no=20&uid=130529&sid=c0&name=001601c68719$db258840$84809e18@ownercgpkrz1hx