Taoists call it yin and yang; Buddhists refer to the two truths: existence is both absolute and relative. Just as physicists accept that a subatomic particle is also a wave, we can understand that the universe is both one (absolute, undivided) and many (conceptual, material). Mystics get lost in the absolute, while most of us see only the relative. Matt Mullen points out that both are necessary for living a life in concert with the way things really are.