Have you ever thought about what that your brain comes up with isn’t exactly what your eyes are seeing? Your brain is constantly interpreting everything you see.
At first, you probably see a triangle with a black border in the background and an upside-down, white triangle on top of it.
Figure on the right.You see triangles, but they are not really there.
In reality, there are merely lines and partial circles. Your brain creates the shape of an upside-down triangle out of space because that’s what it expects to see. This particular illusion is called a Kanizsa triangle, named for the Italian psychologist Gaetano Kanizsa, who developed it in 1955.
Figure on the right.You can see the figure which creates a similar illusion with a rectangle.
Optical illusions show us the errors Optical illusions are examples of how the brain misinterprets what the eyes see. For example, in the picture on the left, the line on the left looks longer than the line on the right, but they’re actually the same length. Named for Franz Müller-Lyer, who created it in 1889, this is one of the oldest optical illusions.