From the late 18c to the early 19c in Chosen dynasty, when Jung Yak-Yong lived, it was a period of rapid change in political and social aspest. That is a kind of turning point in chosen dynasty. Therefore depend on the change of his political and social situation, his comprehension on the study of Han and Song`s classic understand was starting to change. But after his exile he newly achieved his view of confucian classics. He thought that to come the truth, we must eliminate our prejudice from the concern of political and social understanding and must understand the classics with unprejudiced view. That denends middle way and justice from the political prejudice as well. That is why his view and utterence could be very meaningful at that historical turning point.