세종의 역법 제정과 『七政算』

Abstract

More than twenty years were required for King Sejong (r. 1418-1450) and his astronomers to pursue and accomplish a unique calendar system for the first time in Korea. Almost half of the entire period was required to acquire Shoushili (授時 曆), a Chinese calendar. The second half was focused on reducing the errors which occurred while predicting eclipses according to the Shoushili calendar and on establishing Korea's own calendar system, Chiljeongsan (七政算). In this paper, evidence of reorientation during the latter half to new goals to attain higher level tools for eclipse calculations are traced. The influence of the long period of exertion, which was devoted to gain a better prediction process and of the newly equipped astronomical instruments on the sequel system of Chiljeongsan Naepyon (七政算內篇) was also investigated. To account for the roles played by important figures during the determination of the features of the first calendar system for the Joseon dynasty, comments are added about Chiljeongnyok (七政曆), an almanac, and about Chiljeongsan Oepyon (七政算外 篇), the Korean version of a Chinese-Arabic calendar, both of which were enacted and published during the latter part of the aforementioned period.