Virtual Bumps

July 13, 2008
Posted by Jay Livingston

Optical illusions. I had always thought of them as fun, like a joke. Interesting too for speculation about abstract matters of perception or cognitive science. This blog has even had a post about one very small but useful application of trompe l’oeil.

Yesterday’s New York Times has a story about trompe l’oeil speed bumps. If you’re driving and you see these in the road ahead of you . . .


. . . you’d probably slow down. At least the first time. After that, you might realize that these “bumps” were really two-dimensional representations.

I wonder if the traffic people in Philadelphia took their idea from artists like Julian Beever.


The illusions as photographed are wonderfully deceptive. But they fool the eye only from certain angles. Look at this sidewalk swimming pool. That’s Beever himself about to test the water with his toe.


Now look at this same sidewalk from a different angle.


Oh well, maybe the Philadelphia drivers will slow down just to admire the art.