We know, more intimately than anything else, what it's like to undergo a rich world of experiences: agonizing pains, dizzying pleasures, heady rage and existential doubts. But, despite the incredible advances of physical science, it seems that we're no closer to an explanation of how this inner world of experiences comes about. No matter how detailed our description of the physical brain, perhaps we'll always be left with this same question: how and why does the brain produce consciousness?This ...