The trick that makes spot-the-difference puzzles ridiculously easy

Daniel Wirtz thought he was watching a child prodigy at work. The 9-year-old girl on a German game show was solving complex spot-the-difference puzzles in seconds. "To my eye, both images looked exactly the same," Wirtz writes in his blog. "But it took her only a couple of seconds to call out that one coffee bean was missing."

A Redditor revealed her secret. She crosses her eyes to make the images merge. "For a moment, the images just seemed to blur over each other," Wirtz describes. "But then suddenly, the images seemed to lock together in the middle, creating a third image between the two others that I was able to focus on."

He includes some examples in his post to try out the technique for yourself.

Previously:
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