Opening of office to secondary sons and the petitions of the jungin
In late Joseon the seoeol (sons of concubines) and the jungin petitioned collectively against discrimination in office. Under Jeongjo the way opened for the seoeol, and in 1851 restrictions on them were largely lifted.
The seoeol, descendants of yangban by concubines, were barred from the civil examination and, even when appointed, could rise only to a limited rank. In late Joseon they demanded an end to this discrimination through collective petitions. In 1777 Jeongjo issued regulations opening office to them, and appointed seoeol scholars such as Yi Deok-mu, Yu Deuk-gong, Park Je-ga and Seo I-su as editors (geomseogwan) of the Gyujanggak. In 1851, under Cheoljong, the Sinhae opening admitted them to the prestigious posts.
Inspired by this, the jungin — who held technical posts and administrative duties — launched a large petition movement in 1851 demanding access to the prestigious posts, but it was rejected. The jungin formed poetry societies, developing a literature of the alleys (wihang munhak) and publishing joint anthologies such as the Sodae pungyo and Pungyo sokseon. Interpreters and others who travelled to Qing absorbed new knowledge and formed one strand of the Enlightenment thought.
