While a camera can directly measure the amount of light it is picking up, [Dr. Dale Purves] said, “we don’t have that physical apparatus, we have no measurement of the world.”
Instead we have “an eye with a brain attached,” Dr. [Bruno] Laeng said. When the eye is confronted with a scene, your brain “is analyzing what it’s seeing and building up, constructing a possible scenario and adapting to it.” ...
Seeing the expanding hole illusion is not a flaw, but a feature: It’s the result of your brain’s strategy to navigate an uncertain, ever-changing world, most likely built up from evolutionary history to ultimately help humanity survive. It is adaptive to predict the future by, say, dilating your pupils in anticipation of going somewhere dark.
“It’s a very philosophical question,” Dr. Laeng said. “We do live in a virtual reality, but it’s a pragmatically useful virtual reality.”
