In an earlier publication called Consciousness, A New Slant on an Old Conundrum, I made the case for a cognitive duality in human beings--a duality (not left/brain versus right/brain) that is supported by anatomical, physiological, and evolutionary evidence. The brain and nervous system evolved to allow for straight-ahead navigation. To navigate requires physiological bilaterality and a dual-sensorimotor control system (the mind). Consciousness is a sense (like seeing and hearing) and there are two kinds of consciousness. Chapter One of this book summarizes this theory and provides the supporting logic and evidence. Because of our unique cognitive duality, we have the potential to evolve through levels of consciousness. These levels are the focus of Chapter Two. Conflicts and responsibilities arise because of these levels of consciousness and because of cognitive duality. Chapters Three through Eight explore different disciplines--for example, religion, philosophy, and psychology--that have grappled with our innate human duality, and the confusion caused by being our own twin. Knowledge of our complex cognitive design comes with a deep responsibility to evolve individually and collectively.