Created by Kokichi Sugihara, a math professor at Meiji University in Tokyo, the “Ambiguous Cylinder Illusion” wowed audiences at "the Best Illusion of the Year Contest" in 2016. Here's the general gist of the illusion:
The direct views of the objects and their mirror images generate quite different interpretations of the 3D shapes. They look like vertical cylinders, but their sections appear to be different; in one view they appear to be rectangles, while in the other view they appear to be circles. We cannot correct our interpretations although we logically know that they come from the same objects. Even if the object is rotated in front of a viewer, it is difficult to understand the true shape of the object, and thus the illusion does not disappear.
So how do those rectangles look like circles, and vice-versa? The video below--if you care to spoil the illusion--will show you. Find more videos from the Illusion Contest here.
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