The 22th King, Jeongjo, of the Choseon Dynasty, has various nicknames such as the monarch for the people, for reformation or of literary, but he also called ‘monarch of filial piety’. King Jeongjo showed the extraorinary affection toward King Yeongjo, the grandfather, SADOSEJA, the late Crown Prince and Hyegyeonggung Hong, the mother, as a sovereign monarch and filial son.
One of his high virtues extolled by the contemporary or today people is his filial piety toward SADOSEJA, the Crown Prince. Suffering from the grief of losing his father at the age of 11, he was crowned despite of emotional distress and conspiracy against his throne from the opposite political group.
The eight-word remark, 'No throne for the son of the traitor' (‘逆賊之子 不爲君王’) was circulated in the country to baffle his throne by opposition party, Noron.
Opposition party, Noron had driven the national consensus against his legitimacy saying how the son of SADOSEJA, the Crown Prince who was executed as traitor could be a king.
King Jeongjo was concentrating on his legitimacy as monarch after managing to secure his throne with the help of the guard forces made up of his guests of honor around the Crown Prince Palace Sigangwon (東宮 侍講院) while being a Crown Prince. The project was to extol the Crown Prince of the Apostles. However, December in 1775 (Yeongjo 51), just before sovereign by proxy, the respect of his father, SADOSEJA, was banned the Crown Prince upon the strict order by King Yeongjo, which was a huge hinderance to him. In the long run, the extollment of SADOSEJA, the Crown Prince was the only way to establish his legitimacy, which was barriered fundamentally by Yeongjo.
Accordingly, he needed to establish a new 'Yimoeuiri(壬午義理) ' for his legitimacy established, but in reality, he had to pursue the long-term 壬午義理 toward the completion of the respect of SADOSEJA, the Crown Prince. So he virtue is basically gyeongmogung Palace construction and the respect of the SADOSEJA, the Crown Prince and transfer of the tomb of the Crown Prince to Suwon Provincial Office and at the same time changed its name into Hyunreungwon 顯隆園, and through various type of extollment he wanted to get the attention from officials, royal families and grass roots to discuss the possibility of the respect of SADOSEJA, the Crown Prince, which meant highly political movement through ‘Sajungjigong(私中之公)’ to mobilize his personal piety into the public piety toward his father.
So he wrote King's writing by himself to upheave SADOSEJA, the Crown Prince, directly or indirectly for 'Yimoeuiri(壬午義理) ', and published books for extollment of SADOSEJA. National projects and King's political action were associated with the Crown Prince, in order to focus him on the monarchs of three kings inherited the lineage(King Hyojong, King Hyeonjong, and King Sukjong), who could be the lords with the power of the state administration.
In relating to tomb transfer, he prepared the writing as the biography of SADOSEJA, 『Hyungreungwonji (顯隆園志)』who was depicted to better himself as ‘Swordsman (武)人’ monarch not as psychopathic enough to kill Yeongjo like traitor. In particular, extollment of SADOSEJA, the Crown Prince was made naturally through letting the people know his humility and reasonable policy making for his future subjects.
Let alone this, King Jeongjo utilized Buddhism to promote extollment of SADOSEJA that the grass roots believed in. Comparable to the Confucian "Hyokyung 孝經", the publication of the "Bumoeun Chongqing" was entrusted to Temple Yongjusa, which was the original temple visited by him.
In the preface of "Muyedobotongji", published in 1790, King Jeongjo highlighted that the Crown Prince established the Korean martial art. King Jeongjo translated this book into "Eonmun" (Korean letters for grass roots), to recruit people who wanted to stay in the military camp. These military men were accepted to set up the Jangyoungyong Ouside Camp, which was his own supporting base along with extollment of SADOSEJA, the Crown Prince.
In the end, King Jeongjo was to eventually transcended his piety toward SADOSEJA, the Crown Prince into a national project to change the culture of Choseon society, and promote the new reform under political stability.