The argument about astronomical calendar that he experienced when he was young left an indelible mark on his mind. He witnessed the ministers being at a loss in the face of science and hated his ignorance of science. In the scientific struggle between Yang Guangxian and Ferdinand ferdinand verbiest, he realized that mathematics was one of the keys to their success. Therefore, he studies mathematics hard. Later, when he talked about how eager he was to learn mathematics, he said, "You only know that I am good at arithmetic, but you don't know why I want to learn arithmetic. As a teenager, Han Chinese officials in Qin Tian prison were at odds with westerners, attacking and blaming each other, and many people died. Yang Guangxian and Tang Ruowang are outside the noon gate, making a bet to measure the sun shadow in front of Minister Jiuqing. No one in Jiuqing knows this method. I thought at that time, I don't understand, how to judge whether others are right or wrong? So I am very angry about learning math. "

This is really how he started his scientific activities. He first studied geometry with the Belgian missionary Ferdinand ferdinand verbiest. Ferdinand ferdinand verbiest died in the 27th year of Kangxi (1688), and studied under the French missionaries Zhang Cheng and Bai Jin in Beijing. In order to learn this course well, he prepared good living conditions for the missionaries and told them to study Manchu and Chinese in the Ministry of Internal Affairs. He also studied Latin hard in order to try to understand or understand the math lecture. He studied Euclid's Elements of Geometry and Battis's Practical Geometry and Theoretical Geometry in Manchu. Every time he learns a rule, he should not only try to understand it, but also try to connect with reality as much as possible.

Kangxi not only learned mathematics from foreigners, but also tried to cultivate and unite a group of mathematicians in China. He joined forces with famous mathematicians at that time, and later transferred Mei's grandson to Beijing to specialize in scientific research and compilation. In addition, mathematicians such as Chen Houyao of Taizhou, He Guozong of Daxing and Mingjiatu of Mongolia were also taught by Kangxi.

In his later years, Kangxi established the Arithmetic Museum in Changchun Garden, Beijing. Under his advocacy, Mei Gucheng and others spent ten years compiling a masterpiece, The Origin of Rhythm, Astronomy and Mathematics. The second part of this book is called "Essence of Mathematics", which contains not only the essence of mathematics in China, but also the western mathematics introduced since the late Ming Dynasty. This is a valuable math series.