Daxue yanyi 大學衍義 "Abundant Meanings of the Great Learning" is a philosophical treatise written by the Southern Song-period 南宋 (1127-1279) scholar Zhen Dexiu 真德秀 (1178-1235). The 43 juan-long book is an explanation of the meaning of the Confucian Classic Daxue 大學, one of the Four Books (Sishu 四書).
The author stresses that both a ruler (ren jun 人君) and his officials (ren chen 人臣) had to be clear about the content of this Classic. It was finished in 1229 but was only presented to the throne in 1234, under the reign of Emperor Lizong 宋理宗 (r. 1224-1264), who was very interested in Confucian teachings, but whose political decisions were highly influenced by powerful ministers and the kinsmen of imperial consorts (waiqi 外戚). The Emperor rewarded Zhen Dexiu for his book with the position of academician (xueshi 學士) in the Hanlin Academy 翰林院.
In Zhen Dexiu's book it is clearly explained how a ruler had to investigate all things (ge wu 格物) in order to achieve utmost knowledge (zhizhi 致知) and to make his intentions sincere (cheng yi 誠意) in order to to rectify his heart (zhengxin 正心), with the final aim to appease the empire (ping tianxia 平天下). Zhen Dexiu explains these steps with examples from contemporary times. These were two of the four great guidelines (si da gang 四大綱) for a ruler, while the two others were self-cultivation (xiushen 修身) and equalizing all families (qijia 齊家). The four guidelines were supported by twelve intermediate steps (mu 目 "meshes" between the gang 綱 "outlines"), namely making clear the art of the Way (ming daoshu 明道術), to discern between persons of talent (bian rencai 辨人材), to investigate the system of ruling (shen zhiti 審治體) and to find out the emotions of the people (cha minqing 察民情) for the first "guideline"; the observation of venerating dignitaries (chong jingwei 崇敬畏) and the restriction of desires (jie yiyu 戒逸欲) for the second guideline; being respectful in words and actions (qin yanxing 謹言行) and rectifying one's sense of decorum(zheng weiyi 正威儀) for self-cultivation; and appreciating one's consort (zhong feipi 重妃匹), observing the orderliness in one's home (yan neizhi 嚴內治), fixing the roots of the state (ding guoben 定國本) and instructing one's relatives (jiao qishu 教戚屬) for the equalization of the family. Except for the "guideline" of self-cultivation, there are third-level measures for each theme. Each description is highlighted with quotations from the Classics, historiographical books and the ancient Confucian masters, in order to exemplify their meaning.
The author explains that the root of (society on) earth was the imperial court (chaoting zhe, tianxia zhi ben 朝廷者，天下之本), whose centre was the emperor (ren jun zhe, chaoting zhi ben 人君者，朝廷之本), and the emperor's centre was his own mind (xin zhe, ren jun zhi ben 心者，人君之本). The root of the state was each single family, just like the individual person ist he root of the family. The character (xing 性) of the individual is a reflection of the Heavenly order (li 理), and the human order therefore identical with the will of Heaven. The ruler is the terrestrial representative of the Heavenly will and therefore had to obey Heaven's orders (tianming 天命). Once the Heavenly Way was made clear, it was no more possible to deceive Heaven. The Heavenly will, and therefore also the human character, was purely good. Yet because of individual desires (si yu 私欲) this naturally good character was tainted. This was true for all human beings, except so-called "sage persons" (shengren 聖人).
Kindheartedness (ren 仁) was the strongest virtue among the masses, and therefore also to be desired as "kindhearted government" (renzheng 仁政). A ruler who did not know hat his character is good by nature, would be unable to known that he – and everyone - had the potential to become a sage like the ancient rulers Yao 堯 and Shun 舜. If a person was not behaving in a virtuous manner, this was due to the influence of "matter" (qizhi 氣質). In order to "purify" this substance, learning and teaching were necessary as tools to to remind oneself of one's naturally good character, and to instruct others about this fact. Learning helped preserving the Heavenly order and to discard human desires (cun tian li, qu ren yu 存天理、去人欲). "Goodness" could be divided into great and small. It could be achieved by rectifying the "three guidelines" (sangang 三綱) and the the "six ropes" (liuji 六紀) of human relationship. The guideline of a minister was his ruler, that of a son his father, and that of a wife her husband. Those persons in the senior position had therefore to rectify themselves (zheng shen 正身) in order to rectify their subordinates.
Only that ruler was a good one who was able to discern between officials of talent and the "mean men" (xiaoren 小人) or machinating officials (jianchen 奸臣). In his way to govern (zhiti 治體 "order the corpus of the state") the ruler had to know when to apply reward and punishment (de xing 德刑) and to clarify the difference between (commonsense) propriety and (private) profit (yili 義利). He had to known why the people might turn against him, when they had to cultivate the fields and when could respire. A sage ruler levied light taxes, makes sparingly use of corvée, and does not spend easily the funds of the state. A ruler must forego all his private wishes and desires, must not indulge in pleasures and refrain from expensive enterprises.
Among all virtues, respect (jing 敬) was the most important because without respect, the desire for personal profit would harm all other persons, and all wishes would be without a clear aim. Respect would inevitability result in kindheartedness and sincerity. In the process of self-cultivation, respect was the precondition of all thoughts and comportment, and of tranquil and stable words. Self-restraintment and respect expressed in a ruler's thoughts, words and deeds would be echoed by the lower ranks of the officials and the people by loyalty (zhong 忠), trustworthy (xin 信) and subservience (fu 服). The correct status of a ruler's heart would be reflected by the authority that his proper behaviour emanated (wei yi 威儀). His actions (dongzuo 動作), proprieties (liyi 禮義) and his sense of decorum (weiyi 威儀) had distinct standards, which to follow meant to correspond to the will of Heaven and Earth. Nourishing them would bring fortune and luck. This was also true for the actions, thoughts and conduct of all other persons in the network of human relationship.
Because Zhen Dexiu's book is a purely philosophical treatise on does not mention concrete measures for governing a state, the Ming-period 明 (1368-1644) scholar Qiu Jun 邱浚 xxx wrote a kind of supplement, the Daxue yanyi bu 大學衍義補.
The Daxue yanyi is to be found in the Zhen Dexiu's collected works Zhen Xishan quanji 真西山全集 and the series Siku quanshu 四庫全書, Qinzaotang siku quanshu huiyao 摛藻堂四庫全書薈要 and Xijing qinglu congshu xubian 西京清麓叢書續編.