252 years ago today, on 1 May 1773 (Lunar calendar 1773 March 10), the Qing Dynasty opened the "Four Books" compilation hall. The original letter of the "Four Books" of the Qingdao Cabinet was issued in order to proclaim the rule of Qingdao and the feudal church, and on 1 May 1773 (Juanlong thirty-eight years the beginning of March 10), the Qingdao Dynasty opened the "Four Books" library, commemorated as the general editor. At the time, a large number of prominent scholars such as: Daishu, Shao Feng, Yang, Ming, Liu Xiao, Qingdao Feng, Qingdao Feng, Yiang, Yiang, Yiang, Yiang, Yiang,