Optical illusions are older than you think. The first optical illusions date back to 20,000 BC and took the form of cave sculptings. Nowadays they are found all over the place – on screens, in books ...

Optical illusions are spreading like wildfire on the internet. One such challenge that is going viral on Reddit will leave many experienced players muddled. This viral optical illusion tests the ...

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The famous Ebbinghaus illusion, named for its discoverer, the German psychologist Hermann Ebbinghaus (1850–1909). Despite appearances, the two orange circles are the same size. Have you ever looked at ...

Think you can trust your eyes? Think again. What feels undeniable at first glance is sometimes a surprise, an illusion, or an invisible trick.Ordinary images, patterns, and shapes are windows into the ...