A Mystery: Why Can't We Walk Straight?

A Mystery: Why Can't We Walk Straight? from NPR on Vimeo.
Try as you might, you can't walk in a straight line without a visible guide point, like the Sun or a star. You might think you're walking straight, but as NPR's Robert Krulwich reports, a map of your route would reveal you are doomed to walk in circles.
By Benjamin Arthur
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