If you really want to learn the compass, there is a book for each circle. Each book is equivalent to 6-8 college credits. After completing 25 levels, you will graduate from a bachelor's degree in four years. A general understanding of Wu Mingxiu's compass, Qin Lun's poem's compass, Wang Tingzhi's compass, Wu Jinguo and Zhong Yiming's Xuankong, Zhang Wuzhe's Xuankong hexagram, Lianshan Guizang's twenty-eight constellations and gold. , can be used as a blue book for entry and further study.