I saw it with my own eyes

You generally believe what you see, indeed the expression "I saw it with my own eyes" conveys a sense of truth about a witnessed event. The mindbender below is quite amazing. It was produced by Edward Adelson of the Department of Brain and Cognitive Sciences at the Massachusetts Institute of Technology. Thanks for Pilgrims' fan Adam Hallgarth for suggesting to me that it would make a good Mindbender. When you see the solution, you won't believe it, but it is true. You will certainly think twice about calling out "Did you see that referee?" at the next match!

The puzzle

A very simple question. In the figure below, which square is the darker, A or B?

Adelson Illusion

The solution

Amazingly squares A and B are identical shades. The shades of light and dark around each square confuse your brain into interpretting the relative shades of the squares incorrectly. Most people do not believe it when they are told the solution, they need proof! So try printing out this page then cutting out the two squares and placing them side by side without their surroundings. If you do this you should get something like the figure below, where you can clearly see both squares are the same shade.


Back to Boston United Home Page. Back to the Mindbenders