Which book does "Learning from history help us know the ups and downs" come from? Which page?

Source: "Old Book of Tang·Biography of Wei Zheng"?

Li Shimin: I use copper as a mirror to dress my clothes, history as a mirror to know the rise and fall, and people as a mirror. Can know the gains and losses. Use the successes and failures in history as lessons. Same as "learning from the past".

Anecdotes

In the 17th year of Zhenguan in the Tang Dynasty (AD 643), Wei Zheng, who was outspoken and dared to remonstrate, died of illness. Emperor Taizong of the Tang Dynasty was very sad. He said with tears: "I use copper as a mirror to correct my clothes; I use history as a mirror to know the ups and downs; I use people as a mirror to know gains and losses. If Wei Zheng is gone, I will be dead as a mirror!"

“If a person uses copper as a mirror, he can see whether his clothes and hats are well-dressed; if he uses history as a mirror, he can know the reasons for the rise and fall of a country; if he uses people as a mirror, he can see whether he is right or wrong. Wei Zheng Once I die, I will lose a good mirror." - This is the best explanation of the value of Wei Zheng's life. Nowadays, some people also say: "We can use the past as a mirror to know the ups and downs." The meaning is the same.

Using copper as a mirror, you can organize a person's clothes; using history as a mirror, you can know the rise and fall of history; using others as your own mirror, you can know your gains and losses every day.

Extended information:

The "Old Book of Tang" has 200 volumes, including 20 volumes of "Benji", 30 volumes of "Zhi", and 150 volumes of "Biography". It was originally called "Tang Dynasty". After the "New Book of Tang" compiled by Song Qi, Ouyang Xiu and others came out, it was renamed "Old Book of Tang" and was completed in the second year of Kaiyun of the Later Jin Dynasty (945). ?

The "Old Book of Tang" was compiled not far from the fall of the Tang Dynasty, and the sources of information are relatively rich.

However, the "Old Book of Tang" only circulated for about a hundred years before it encountered bad luck. Starting from the Qingli period of Emperor Renzong of the Song Dynasty, the Northern Song Dynasty court believed that the "Old Book of Tang" was messy and unrefined, and ordered Song Qi and Ouyang Xiu to compile the Book of Tang. This book of the Tang Dynasty was written in 1060 (the fifth year of Emperor Renzong's reign in the Song Dynasty) and began to be "distributed throughout the world". From then on, the Tang book signed by Liu _ was no longer circulated. Until 1538, the seventeenth year of the Jiajing reign of the Ming Dynasty, Wen Renquan, a native of Yuyao, Zhejiang, borrowed the "Old Tang Book" collected by local people in Suzhou, and asked Suzhou Prefecture to teach Shen Tong in Suzhou. In the Fu School, the manuscript was proofread and printed (in the middle of the work, Wen Renquan left Suzhou, but the matter continued with the support of many parties). After four hundred and seventy-eight years of ups and downs, Liu_Tang Shu, Only then was it reissued.

In order to distinguish the two Tang books, later generations called the Tang books written by Liu Zhi in the later Jin Dynasty the "Old Book of Tang", while the Tang books revised by Song Qi and others later were named the "New Tang Book". After the "New Book of Tang" came into being, the "Old Book of Tang" was almost abandoned by people for a long time.

Reference: Baidu Encyclopedia-Old Tang Book