It means that if you use copper as a mirror, you can organize a person's clothes; if you use history as a mirror, you can know the rise and fall of history; if you use others as your own mirror, you can know your gains and losses every day. \r\n"Using history as a mirror, we can know the rise and fall; using people as a mirror, we can know the gains and losses" comes from "Old Book of Tang Wei Zheng Biography".

\r\n\r\n"Old Book of Tang·Biography of Wei Zheng": In the seventeenth year of Tang Zhenguan (AD 643), Wei Zheng, who was outspoken and dared to remonstrate, died of illness. Emperor Taizong of the Tang Dynasty was very sad. He shed tears and said: "Husband, If you use copper as a mirror, you can straighten your clothes; if you use history as a mirror, you can know the ups and downs; if you use people as a mirror, you can know gains and losses. If Wei Zheng is gone, I will be dead as a mirror!"\r\nA person who uses copper as a mirror can see the mirror. You can see whether your clothes and hats are well-dressed; using history as a mirror, you can know the reasons for the rise and fall of a country; using people as a mirror, you can discover your own rights and wrongs. When Wei Zheng died, I lost a good mirror! This can be called a reflection on Wei Zheng's life. Highest rating for value.