Keep your eyes on the dot. Is it in front, or in back of the cube? In front or in back - That is the question!
Is the book face-down?
Or face-up?
There are 9 people in this picture.
Can you find them all?
One face?
Or two profiles facing each other?
In this illustration, the stairs should turn upside down during a steady gaze. The wall with the floating glass sphere will shift from the foreground to the background. Of course, if you originally saw the background as the foreground, you will notice a change from the background to the foreground.
The white triangle looks very real, although there's no triangle per se.
Which Soldier is Taller?
Believe it or not, they are the same height! Take a ruler and measure them!
Actually both! A polar bear crawling out of a hole in the ice and a seal laying on the ice facing to the left!
Is This the Father or the Son?
Actually both! The father is looking towards your right with his chin resting on his chest and the son is looking away from you over his left shoulder. Notice how the nose of the father forms the chin of the son!
A lady siting in front of a mirror or something else?
From the 2013 version of the site. Details, prices and links may be out of date, so check them against your own campus policies.