In 36 1 year BC, Qin Xiaogong succeeded to the throne and ordered him to look for talents. Shang Yang entered Qin with Li Kui's Fa Jing, presided over the reform of Qin State, carried out a relatively thorough reform, established a new feudal system, changed "Fa" into "Fa", and formulated the Qin law based on the Fa Jing. Shang Yang's political reform was a profound change, which was the most successful in the Warring States period in depth and breadth. At the same time, it also provided valuable experience for the establishment of feudal system. Zi chan was a politician and a pioneer of legalist thought in the late Spring and Autumn Period. From 543 BC to 522 BC, Zheng was in power. In 536 BC, Zheng's ruling son made "Casting Punishment in the Ding, Thought it was the customary law of the country", and cast the legal provisions on the Ding and made them public, which was called the Criminal Code in history. It is an epoch-making legal event in the legal history of China, which declared the end of the legal form of slavery in China, opened the prelude to the birth of feudal statute law and laid the foundation for the development of feudal dynasty statute law. At the end of the Spring and Autumn Period, Deng, a statesman and pioneer of legalism, was once a doctor of Zheng State, and Deng's Bamboo Punishment: that is, in 502 BC, Dr. Deng of Zheng State revised the Law of Zheng State and wrote it on bamboo slips, which was called Bamboo Punishment. Yu said in the note of Zuo Zhuan: Deng "wanted to change the old criminal system cast by Zheng, but did not listen to your orders, which was a private criminal law." The book is on the bamboo slips, so it is called bamboo punishment. " Deng's Bamboo Punishment was originally a private work, but it had a great influence at that time. Later, Deng was killed by the ruler for political disputes. However, because he privately accepted disciples and taught the law, his Bamboo Punishment was still circulated in Zheng, accepted by the rulers and later became an official law. He was the first to oppose the rule of courtesy, attach importance to the law, and advocate "legal cause", which laid the foundation for the formation of Legalist thought of rule of law. In order to ensure the smooth progress of the political reform, Wei Xiang and Li Kui wrote the Law of Nations, that is, they studied the laws of various countries, absorbed the legislative experience of various countries, and formulated the Basic Law of Wei, that is, the Classic of State Law. The original text of the Classic of Law has long been lost. In terms of content structure, the Classic of National Law consists of six articles: theft, thief crime, prison law, arrest law, miscellaneous law and armed law. Li Kui thought that "the king's government should not be eager to be a thief", so he listed the Theft Law and the Thief Law at the top of the code. The Classic of National Law stipulates all kinds of major crimes, penalties and related principles of legal application, which has covered a wide range of contents. Its basic characteristics are to maintain the feudal autocratic regime, protect the private property of landlords and the remnants of slavery, and implement the legalist thought of "light punishment for crimes".