During the period of Song Shenzong, Sima Guang was highly valued, and at the same time, there was another person who was highly valued. This man is Wang Anshi. In contrast, Wang Anshi received more attention and was promoted to be the political governor (equivalent to the prime minister) to preside over the political reform. Sima Guang and Wang Anshi have different political views. When Wang Anshi introduced the young crops law, Sima Guang strongly opposed it.
The strong opposition of Sima Guang and several ministers failed, but was ousted. In a rage, Sima Guang went home and demoted himself to Xijing Yushitai. Since then, he has lived in Luoyang for fifteen years, regardless of political affairs, and began to concentrate on compiling "Lessons Learned from Mutual Aid".
This book is not written for ordinary people, but for the emperor, in order to consolidate the feudal regime at that time. He divided the monarchs in history into five categories according to their abilities: pioneering, persistence, paranormal, resurgence and chaos. In order to show the emperor the methods, strategies and ideas of governing the country and the people.
Hu Sansheng, a historian at the turn of the Song and Yuan Dynasties, said: "If you don't know the mirror, you will want to govern without knowing the source of autonomy, and if you are evil, you won't know the art of preventing chaos. If you are a minister and don't know Tong Jian, then you have nothing to do with the monarch and nothing to do with the people. ..... This is like using soldiers and teachers to create laws and regulations. I don't know what the ancients got, but it is inevitable to lose and win. "
In other words, "Learning from the same experience" is that Sima Guang lists all the emperors in ancient times, comments on everyone's gains and losses, analyzes the pros and cons, finds out the rules, summarizes the experience and finds out the ways to govern the world. This is actually the emperor's "dictionary" and a reference book. What should the emperor do when he meets something? Just look through the books and find a case.
In today's words, "Learning from the Same Resources" is the emperor's "management" reference book.
Of course, "Purple Tongzhi Sword" does not stop there. It shows us the history of 1362 years with detailed information, spanning China 16 dynasties. "Delete superfluous words, introduce confidential information, focus on the rise and fall of the country, care for the people, take good as the law, take evil as the warning, and make it coherent and refined."
Song Shenzong thought that this book "in view of the past, has the resources to govern the Tao", that is, to take historical gains and losses as a warning and strengthen the rule, so it was named as "Learning with Resources as a Mirror".
Zi Jian's position is very high, which can be compared with Historical Records, and he is also called "the historian of the Second Sima" with Ma.