Is the square in the middle a perfect square?

Although it is a perfect square, the sides may appear to bend inward.

Depending on how you look at this image, you may see a portrait of a woman, or a silhouette of a man playing a saxophone.

mall grey dots should appear at the intersections of the squares, but if you look directly at the intersection, the grey dots will disappear.

In spite of what your eyes are telling you, the smaller off-center circle is actually perfectly round.

Look at the center of the image for about 30 seconds. Then quickly shift your gaze to somewhere with a white background. You should see an afterimage of the US flag with the correct colors! This happens because your eye reverses the colors in afterimages.

Are the holes on the inside or outside?

Do the straight horizontal gray lines look curvy to you?
Hold up a piece of paper to prove that they are straight and parallel to each other.

How many legs does this elephant have?

Can you see both the duck and the bunny in this ambiguous drawing?
The duck’s bill is the bunny’s ears. This was first used by a psychologist named Joseph Jastrow in the early 1900s.

Some people only see three angled lines, but if you look carefully you can actually see the letter E in the empty space.