Wild About Math! Making Math fun and accessible

14Dec/093

Very disturbing optical illusion

I really like optical illusions. Until recently, my favorite was this one. But, I have a new favorite now.

Here's one that bothers me. See if it bothers you.

Look at the image below. Which square is darker, A or B, or are they the same color?

A hat tip to John Cook for blogging about this illusion.

Comments (3) Trackbacks (1)
  1. Wow! I don’t think I’ve ever seen a more convincing illusion. No matter how long I stare at it or how much I cover up the rest of the image, I cannot see those squares as the same color.

  2. What’s even more disturbing is that you can throw away all of the image except a small square encompassing A and B and the illusion STILL exists (I did so here: http://twitpic.com/tmama … feel free to copy it into this comment).

    BTW, if you paint a white border around B the illusion disappears.

  3. Cut or punch a 1/4 inch hole in an index card and hold the hole over the A and then over the B. Look at the card about an inch or so away from the hole so you can take advantage of your peripheral vision.


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