宋代學術發展除了「理學」興盛，另一個重要現象就是「孟學」的產生，原因來自唐代中葉起，學術界展開《孟子》是否應列為經典的激辯，直到宋室南遷後，因余允文撰著《尊孟辨》，針對北宋李覯、司馬光、蘇軾、鄭厚，甚至是遠溯漢代王充等人「非孟」觀點，分卷提出具體辯駁，終令「尊孟」得到學術界共識，為朱子編定《四書集注》加入《孟子》取得尊崇地位。同時余允文《尊孟辨》，也成為協助《孟子》從原本「諸子」類，晉陞為「經部」過程中的重要文本，更因為原文保留許多「非孟」相關著作，對研究古典文獻學亦有助益。

Song Dynasty academic develops, except that ”Neo-Confucianism” prosperous. Another important phenomenon has ”Meng to study”. The reason is starts since the Tang Dynasty intermediate stage, academic circle regarding ”Mencius” whether should list as the classics to have the sharp debate. Until the Southern Song Dynasty, because Yu Yun-Wen the work ”Reveres Meng To distinguish”. To Northern Song Dynasty Li Gou, Sima Guang, Su Shi, Zheng Hou, even traces back to go back to Han Dynasty Wang Chong et al. far ”Non-Meng” the viewpoint. Proposes the different viewpoint. Lets ”Revere Meng” finally to obtain the academic circle mutual recognition, compiles and checks ”Four Books for Zhu Xi To collect” joins ”Mencius” obtains the lofty status. Yu Yunwen the work ”Reveres Meng To distinguish”. Becomes assists ”Mencius” from the original manuscript ”the pre-Qin thinkers” the kind, promotes for ”the classics” in the process important work. Because retains many ”Non-Meng” the related work, to studies the classical literature study also to have the help.