Joseon's sedo politics(勢道政治)?a type of political mechanism that was controlled by some powerful family clans?developed during the early 19th century. While those involved with sedo politics adopted the advantages of the Tangpyeong policy(蕩平策, policy of impartiality), they also distorted it in order to preserve their families' political power. The Tangpyeong policy was first established in the 18th century by King Yeongjo(英祖) and King Jeongjo(正祖) as a means of carrying out a comprehensive socialreform.
However, after the death of King Jeongjo, certain powerful clans ceased to support the reform efforts which he had undertaken, and formed the so-called sedo politics structure by placing more emphasis on the principles of righteousness and reason(義理論) as developed by the Chu Hsi school of thought(朱子學 義理論). Political theories such as that of the virtuous monarch(君主聖學論), moralistic politics(世道政治論), and governance through moral practices(道學的 經世論) were also used to justify sedo politics. While the political structure based on such theories was first formed during the 17th century, it found itself under attack in the 18th century as a result of the emergence of the above-mentioned Tangpyeong policy and widespread reform efforts. However, tlrshis structure was resuscitated in the 19th century through the formation of sedo politics by a few politically powerful families.
These political principles were combined with a centralized bureaucratic system centered on the Bibyeonsa(Border Defense Council), whose own power was strengthened during the 18th century. As a result, sedo politics deepened the inherent contradictions within Joseon's feudal system, eventually leading to the emergence of peasant uprisings. The peasant uprisings of 1862 were a historical event which proved that these political principles were in fact obstacles to progress. In response to this national crisis, the Joseon government established a tax reform policy(三政釐正策) designed to equalize the tax burdens. This turn of events sheds some light on the role which the resistance of the people(民) played in overcoming such governance theories based on the principles of righteousness and reason(義理論).