What is the main cause of an optical illusion?

Answer 1

I believe we have optical illusions to make our eyes and brains think in different ways then they normally think! Without optical illusions, we wouldn't look at things the way we look at them... i guess(?).

Answer 2

Optical illusions come in many forms. The interesting thing about optical illusions, though, is that is not the subject of the illusion that causes it. The main cause is actually how the eye perceives the image.

Answer 3

Optical illusions can be very deceiving. They are caused by the structure of the brain and the eye and how they both work among each other.

Answer 4

Kinesthesis interferes with the perception of depth.