Tang Taizong's famous saying "If you use people as a mirror, you can know your own gains and losses." It means: Using people as a mirror, you can know your own gains and losses.

Original text: (Tang Taizong) sighed and said: "Use copper as a mirror to correct your clothes; use the past as a mirror to know the rise and fall; use people as a mirror to know gains and losses. I try to protect these three mirrors. Be on guard against your own faults. Now that the Wei Dynasty has passed away, I have sent someone to his home and found a piece of paper, the first half of which was written. He said: "There are good and bad things in the world. If you appoint good people, the country will be safe." Using evil people will bring harm to the country. Among the officials, there is love and hatred. Those who hate only see the evil. Between love and hatred, it is advisable to be careful. If you are good, don't doubt it, and appoint talents without guessing, you can prosper. 'I think about it, I may not avoid it. The ministers can write it to Hu (hù), and they will give advice." /p>

Translation: Emperor Taizong of the Tang Dynasty sighed and said: "Use copper as a mirror, so that you can wear it in a dignified and neat manner; use history as a mirror, you can know the rise and fall of the past dynasties; use people as a mirror, you can know yourself. Regarding my own gains and losses, I once kept these three mirrors to prevent my own mistakes. Now that Wei Zheng is dead, I have lost one mirror. I recently sent someone to his house and found a manuscript, which was only half written. It can be understood that there are good and bad things in the world. If good people are appointed, the country will be stable, and if bad people are appointed, the country will decline. If you like and hate, you can understand the shortcomings, and you can understand the advantages and eliminate them. The evil will flourish without hesitation, and the virtuous will be appointed without suspicion." The general content of the book is like this. I think about it all the time, lest I make a mistake. The officials and ministers can write on the wat (hù) board, and those who know that they can give advice must do so.

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