The brain makes MANY, MANY “mistakes”.
The girl on the right looks twice as large as the girl on the left.
But in reality, these two girls are the same size. This is a neat little trick involving elevation and distance from the viewer.
Look at the two yellow lines below. Which is larger?
Wait for it… they’re the same size.
Once again, your mind is playing a trick on you. Although linear perspective allows you to see depth through a single eye, it also makes judgements about size based on background, even when those judgements aren’t necessarily true.
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Our brain is wired to see the triangle that really isn’t there. It fills in the blanks looking for wholes, so instead of seeing line segments and pac mans, it sees a triangle.