When the brain activity is kindled in the right spot, people hear voices. If a physician prescribes an anti-epileptic medication, the seizures go away and the voices disappear. Our reality depends on what our biology is up to.

The brain "fills in" the missing information from the blind spot. Notice what you see in the location of the dot when it's in your blind spot. When the dot disappears, you do not perceive a hole of whiteness or blackness in its place; instead your brain invents a patch of the background pattern. Your brain, with no information from that particular spot in visual space, fills in with the patterns around it. You're not perceiving what's out there. You're perceiving whatever your brain tells you.

In our current understanding of science, we can't find the physical gap in which to slip free will - the uncaused causer - because there seems to be no part of the machinery that does not follow in a causal relationship from the other parts.

Vision is more than looking.

Among all the creatures of creation, the gods favor us: We are the only ones who can empathize with their problems.

As we develop better technologies for probing the brain, we detect more problems.

Visual cortex is fundamentally a machine whose job is to generate a model of the world.