Be sure to gaze at the amazing checkershadow illusion. Go now, then come back here.
A cursory check with a little computer program I have (Digital Color Meter in /Applications/Utilities/ for those of you with MacOS X) verifies that the two squares which look so different are, in fact, the same 42% grey. But the surely don't look the same. The explanation is helpful.
I’m Greg Restall, and this is my personal website. ¶ I am the Shelby Cullom Davis Professor of Philosophy at the University of St Andrews.
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