Have you ever looked at an object in the mirror and seen something totally different? That’s how the objects in the video above feel.
As presented by Kokichi Sugihara, finalist in the Best Illusion of the Year Contest 2016, the video shows a figure that looks like one shape when looked at directly and another shape when looked at through a mirror. It’s called the "ambiguous cylinder illusion."
How is this sorcery done? It’s actually quite simple: The shape is cut and viewed at just the right angle to produce a different reflection than what one sees from looking at it from the front. Devin Montes of the YouTube channel Make Anything explained how it works by 3D-printing his own version:
The whole thing shows the weird relationship between our brains and our eyes. As the Best Illusion of the Year Contest site explains, "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."