Hear Exploratorium's founder, Frank Oppenheimer, talk about his fascination with mirrors in this excerpt from NOVA's Palace of Delights, produced in 1982. The Anti-Gravity Mirror, featured in the video, is one of the Exploratorium's oldest and most favorite exhibits.

If you stand with the edge of a large mirror bisecting your body, you will appear whole to a person who’s observing from the front. To the observer, the mirror image of the visible half of your body looks exactly like the real half that is obscured behind the mirror. 

You look whole because the human body is symmetrical. The observer’s brain is tricked into believing that an image of your right side is really your left side. So just straddle the mirror, raise one leg, and you’ll fly!