This study explores an argument between Wu, Rulun(1840-1903) and Zhang, Yuzhao(1823-1894). It is mainly about the "Three Rivers" issue in "Shang Shu·Yu Gong", which was carried out intermittently from 1887 to 1888.
This argument began with an article by Zhang Yuzhao, which was the "Contemplation on “three rivers”in Yu Gong". In this article, he mainly pointed out that Ban, Gu was inevitably wrong in "Hanshu Dilizhi", and then advocated that there is another Nanjiang River other than the Beijiang River and the Zhongjiang River associated with the Yangtze River. This is simply an unprecedented insight, because the Sanjiang theory has always referred to three parts of the Yangtze River or three Rivers diverted from the Yangtze River.
As far as the theoretical structure is concerned, Zhang, Yuzhao is mainly based on Guo, Pu's Sanjiang theory: Lijiang, Songjiang, and Zhejiang, which led to the new proposition that Nanjiang is a river. Wu, Rulun verified it in all aspects, and Zhang, Yuzhao refuted it. In the debate, they involve a wide range of academics, sometimes classics, sometimes texts, lexicons, geography, and so on. This shows that they are also well-versed in many academic fields.
At the same time, it is commendable that they strive to put the above academic methods and attitudes into education. The "Contemplation on “three rivers”in Yu Gong" mentioned at the beginning is written for the purpose of education.
By examining the beginning and end of the debate, although it is impossible to determine who wins or loses, it is estimated that Zhang, Yuzhao’s claim cannot be successfully recognized by Wu, Rulun. However, regardless of the outcome, this controversy makes sense, that is, they absorb new knowledge at the end of the 19th century and boldly challenge academic stereotypes, which are valuable in themselves, especially their profound knowledge of geography. In fact, this is the main background that touches the debate.