I try to newly comprehend comparatively old themes on the establishment of Eastern vs. Western party in the year of 1575 from the socio-economic views. I found out some new facts through this research. That is, the economic situation in the late reign of King Myeongjong and the early reign of King Seonjo, or the mid and late 16th century, had gotten worse and fallen down to collapse of Joseon Dynasty. This conclusion was very different from the dominant views that the economic growth had been continued all through the 16th century.
The second, I tried to figure out the political characteristics of the Sarim Faction(士林派) by checking out their reformation issues after they grabbed political power in King Seonjo reign. I verified the Sarim Faction divided into the conservative group which tried to resist against any reformations and the progressive group which intended to construct new state through strong reformation oriented policy. At that time, reformation issues were divided into the way of ‘enlightening people(敎民)’ which focused on enlightenment campaign to the people led by Sajok(士族) or Neo-Confucian elites and the way of ‘raising people(養民)’ which people had to be rich by operating state's system and institutes.
The ‘enlightening people’ group was comparatively radical because they tried to exclude the state's roll as a factor of reformation, but the ‘raising people’ group was pretty moderate because they acknowledged the state had their own roll to normalize the dynasty. While the radical group gathered to the Easterners in the process of reformation, the moderate group cooperated with the Westerners, or the Conservatives. Two groups fought very fiercely each other to get political initiatives. The political system of Eastern and Western party was established through this conflict in the early reign of King Seonjo, 1575.
I finally checked out the roll of King Seonjo at this political dispute. King Seonjo was never progressive person for whom many Sarim faction strongly anticipated to accomplish reformation saving the state, which was sunken to the deep sea with many chronic misleading factors by kings such as Yeonsan-gun, Jungjong, Myeongjong, and the Meritorious faction(Hun-gu Faction; 勳舊派). He had rather conservative opinions not to reform the state like the Conservatives. Due to his reluctance to the state's reformation, most of all reformations the progressive Sarim faction or Easterners eagerly drove to normalize the state were failed. At that result, Joseon dynasty confronted state's crisis not to be controlled at all by a King or officials as like King Myeongjong and his court already experienced before.