This study examines the issue of the study of knowledge (Ji) in Royal Learning, analyzing the emphasis on knowledge study that encompasses the characteristics of general Seonghak but reflects the specificity of the monarch. The monarch, as a representative of Heaven and a standard of ethics, had to fulfill their responsibilities through thorough discernment between public justice and private desire. This was achieved through reading and lecturing at Gyongyeon, as well as discerning and handling matters related to the royal family and politics.