The Origin of Fa Li was compiled under the personal leadership of Emperor Kangxi Michelle Ye. Emperor Kangxi not only drew up the editing policy himself, but also took out the draft he had accumulated for decades as the material for compiling mathematics. French Jesuit Bai Jin wrote a letter to French King Louis XIV, saying that Kangxi personally explained geometry to Yin Zhi. Kangxi opened a library in Changchun Garden, and sent Yin Zhi to preside over the compilation of Fa Yuan Li. The origin of the calendar is a book about laws, calendars and algorithms. It is a series of astronomical mathematics music theory with high value in the history of science and technology in China. The compilation of ancient and modern books lasted for 28 years, and * * * was divided into 6 parts and 32 yards. This is the largest and most informative book in existence. Ancient and modern books are widely collected and rich in content, ranging from astronomy to geography, including human beings, animals, insects, and even literature and music. It is a collection of books before the Qing Dynasty and a treasure house for researchers in various disciplines to study and continue the achievements of their ancestors.