When it comes to consciousness, nothing allows us to deduce the properties of subjective experience — the redness of red, the bitterness of regret, the warmth of fire — from the mass, momentum, spin, charge, or any other property of subatomic particles bouncing around in the brain. This is the hard problem of consciousness.

Why Materialism Is Baloney: How True Skeptics Know There Is No Death and Fathom Answers to life, the Universe, and Everything
Bernardo Kastrup