Abstract
This paper briefly examines the Book of Changes that is the philosophical background of East Asian ancient mathematics and its collection of complementary(ShíYì), and then examines the structure and contents of GyeSaJeon, which explains the basic principles of Book of Changes as one of ShíYì. GyesaJeon reveals the unique East Asian thought of dealing with numbers in the process of explaining the formation of Eight-Gwae(Bagua) and Sixty-four-Gwae based on Yin-Yang theory. It understands numbers in terms of symbols, not quantitative, and use them to represent characteristics or hierarchy of certain classes, and to explain certain principles. Based on this, the implications of using East Asian mathematics history in the mathematics classroom are discussed.