Examined in this article is the taxation rate employed during the second half of the Goryeo dynasty period, in order to raise our understanding of the taxation rate later adopted by the Gwajeon-beob institution. Among several taxations rates that were supposedly used in the Goryeo period, the “one-fourth” rate and the “one-tenth” rate are especially examined, and results of such research are also compared with the taxation rate of the Joseon period.
First, the “one-fourth” rate. This rate, which we cannot find any traces of being used in the Joseon period, was employed in Goryeo. Considering the examples of military lands and garrison farms, the one-fourth rate of Goryeo seems to have been applied in cases of lands which the collectors did not actually own but were authorized to collect taxes from them. And the taxation rate for ‘Official lands’ are clearly indicated in records as one-fourth. Meanwhile, the rate that would have been applied to “Private lands” are yet to be clearly determined. However, considering the military land cases, a rate similar to the ‘Official lands’ would have been applied to the Private lands as well.
Scholars have believed for a long time that the one-tenth rate was employed during the Goryeo period. Yet before Yi Seong-mu suggested for the first time that Goryeo did employ that rate (and spreaded the idea quite widely), early scholars considered one-fourth as the dominant taxation rate of Goryeo. And most interestingly, the Joseon kings and officials did not believe that one-tenth rate was used in Goryeo either. According to their remarks, it seems like they believed that the one-tenth rate was employed only at the end of the Goryeo dynasty, with the launch of the Gwajeon-beob institution.
There are some historical records that are supposedly testifying to the existence of a one-tenth rate in Goryeo. After the time of Yi Gyu-bo, new Sa-Daebu figures frequently commented upon the one-tenth rate, but only as an ideal concept. They viewed the rate as a method to launch (more like reincarnate) ideal land systems from the past such as Gyunjeon-je(均田制) or Jeongjeon-je(井田制) and therefore suggested the concept more than once. And kings like Chungseon-wang and Gongmin-wang who agreed with the necessity of such reforms, also mentioned the rate as well as ideal land systems in their royal edicts. So, we can say that the one-tenth rate was part of the new Sa-Daebu figures’ “dreams” of an ideal society, and was not a practical taxation rate that was employed in real life.
As a result, it becomes clear that the official rate in Goryeo land taxation was actually one-fourth. Historical figures who lived in the latter half period of Goryeo believed that the land system should be reformed, and newly modeled after the ancient Jeongjeon-je and Gyunjeon-je systems. And in order to do so, they argued that the one-tenth rate should be employed. So, as King Sejong later argued, the one-tenth rate was newly employed with the launch of the Gwajeon-beob system, which was a huge accomplishment on part of the reformer officials.