Engineer's Nightmare How many impossible objects can you find in this fantastic engineering drawing? How many outlandish specifications do you see? There ...

A language as familiar as English is ripe for ambiguity and design. There are powerful wizards among us who can manipulate the symmetry of familiar words. We ...

The rectangle on the left is mostly surrounded by white. The rectangle on the right is mostly surrounded by black. Which rectangle appears lighter? Use the ...

The illusions in this section are driven by the way we see things such as high contrast and color. We have many specialized light receptors, but only a few ...

howing a tourist sitting on a wall in an impossible angle at the Mystery Ridge, Oscoda, Mich. Showing two visitors standing at impossible angles at the ...

The Moon Illusion This is only a demonstration, or representation of the actual lunar illusion in nature. For that you would need the real Moon and Sky. ...

What is the Moon Illusion? It is often hard for an observer on earth to judge the true size of the Moon. The Moon may look bigger or smaller depending on ...

This is only a representation of the actual Moon illusion, and is not the actual illusion itself. However it is a fairly accurate thumbnail of how the Moon ...

Fading Color Dots Stare directly at the cross in the center of this demonstration until you see a green dot appear under each fuzzy purple dot. The green dot ...

There is a delay of about one 10th of a second between the moment we "see" something, and the time when we actually visualize that something; due to brain ...

This window frame looks like it is swinging back and forth. But it's not a window at all, and it is actually rotating in complete circles! The window frame ...

We look for differences in texture, color, and light when we try to pick objects out of a background jumble. When there are little or no visual differences ...