The human body is unquestionably the most complicated machine that any person has ever encountered, and it’s likely to hold that title. Each of the about 6.8 billion people on Earth is composed of a unique set of roughly 100 trillion cells (Whenever you hear the word trillion, be amazed) of a huge variety of types. Each of these cells is way more complicated and elegant than your high school bio textbook said.
Without question, conscious awareness is the most astounding — and most perplexing — aspect of the human brain. It’s what makes us the unique, self-reflective creatures that we are. Consciousness allows us to experience and react to our environment in an apparently self-directed way. We’re not just zombies; we have our own private thoughts, feelings, opinions, and preferences — and these traits allow us to figure out the world and operate within it.
But we are still quite a ways off from understanding how the brain produces phenomenal experience, or qualia. Neuroscientists cannot explain how incoming sensations get routed around such that they can be translated into subjective impressions like taste, color, or pain. Or how we can conjure a mental image in our minds on demand.