On the evening of April 12, 2023, the 17th lecture "Guanya Cross Disciplines Statement" was held simultaneously online and offline in Room 512, Jia Geng Building 2. In this issue, Professor Chen Zhiping, dean of the Institute of Chinese Studies of Xiamen University, is invited to give an academic lecture entitled "Civil Contract Documents and Research on Chinese Economic History".

Under the chairmanship of Associate Professor Liu Xinming, Professor Chen Zhiping first started from the contract and the spirit of contract, and believed that although the term "spirit of contract" was introduced from the West, there was no lack of the spirit of contract in ancient China, and China has adhered to integrity since ancient times, and cited Lin Xiangru and other allusions to explain. Professor Chen pointed out that China has a long history of contract documents, and folk contract documents can be defined as "conventions into customs", which are mainly divided into land transaction documents, real estate transaction documents, commercial documents, the contract, loan documents, various contract documents and others. In order to explain the elements of contract documents more clearly, Professor Chen Zhiping showed us a variety of documents such as land transaction documents and pawn documents. At the same time, Professor Chen also shared his interesting experience of collecting contract documents and those around him, which aroused great interest of the teachers and students attending the meeting.

Subsequently, Professor Chen Zhiping fully affirmed the contribution of contract documents to the study of Chinese economic history, and believed that contract documents promoted the diversification of Chinese economic historical data science; It fills up many deficiencies in the study of local economic history; It promoted and even gave birth to the establishment and progress of Chinese social history. But at the same time, Professor Chen also pointed out that the contract documents have the characteristics of strong regularity and high scattered, so we should avoid the bias phenomenon of infinite enhancement and abuse of historical materials in the process of using folk documents to study history and culture.

Finally, Professor Chen Zhiping had in-depth exchanges and discussions with online and offline teachers and students on how to judge the illegality of contracts and the validity of contracts. Under the summary of Associate Professor Liu Xinming, the lecture ended successfully with a fierce applause!