Even our own psychology is relative. When our hearts were just calm, our bad thoughts rose up. When our troubles are extremely painful, we really hope to be quiet. Use yin to represent trouble and pain, and use yang to represent tranquility. You know that there will be no absolute tranquility, and there will be no absolute troubles. Because cathode yang, anode yin is inevitable. No matter how the phenomenon changes, the ontology of Tao is immovable. Being able to understand this principle and grasp this principle is "the successor is good". In other words, if good and evil represent yin and yang, there must be good and evil, there must be good, and good and evil must be opposite.