This is not an optical illusion, but it takes advantage of exactly the same principles that make optical illusions work: Our eyes and brain don't scan reality like a camera does. Instead, the brain interprets external inputs, building its own reality. No spoilers, just watch.
It has always blown my mind that our brain can feel so imperfect—yet this is only a symptom of how perfect it is, how efficient it got at processing information through a hundred thousand years of evolution, optimizing our perception to increase our chances of survival.
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