Illusions

Are Square A and B the same shade of gray?? The answer *Yes*

You are Looking up or looking down?

How many coloumns in this picture?

One or two faces??

Look at the light bulb for 30 second, then look at the white surface... what did you see? *The light should be glowing*

Stare at the centre of the flag for 30 second, then look at a white surface.