東アジアの思想と構造 This paper examines the commentarial tradition of the Hakuen Academy of the Confucian classic The Doctrine of the Mean. Recent years have seen an increase in research into the Hakuen school, and much light has been shed on various aspects of the school’s history and philosophical and philological studies.However as yet no study has looked at the Hakuen school’s research on The Doctrine of the Mean. This paper is an attempt to uncover how The Doctrine of the Mean was interpreted by the Hakuen school, and what were the unique features differentiating their interpretation from other Japanese Confucian scholars. After examining the various commentaries and glosses on the text of The Doctrine of the Mean left by the Hakuen school, the following three unique characteristics have come to light. Firstly, the original text of The Doctrine ofthe Mean was divided up into chapters in a way different from other Confucian schools. Secondly, although the Hakuen school derives its basic methodology from Ogyū Sorai’s （1666-1728） thought, their interpretation of The Doctrine of the Mean shows a strong independence, often going against Sorai’s own interpretation of the text. Thirdly, Fujisawa Nangaku （1842-1920） argues in a section of his Lectures on ‘The Doctrine of the Mean’ that through constant self discipline and moral self-cultivation man is in the end able to become a sage. This is a view unique amongst followers of the Sorai school, who believed that man is not capable of attaining to the level of a sage through his own endeavours. Much still remains to be uncovered about the Hakuen school’s interpretation of The Doctrine of the Mean. It is hoped however that this paper will have shed some light on this neglected area of Hakuen studies.