**1800th Anniversary of the Birth of Liu Hui**

Liu Hui, from Zouping, Binzhou, Shandong Province, was a great mathematician during the Wei and Jin Dynasties and one of the founders of Chinese classical mathematical theory. His masterpieces Jiuzhang Suanshu zhu (Annotation on the Nine Chapters of Mathematics) and Haidao Suanjing (Sea Island Mathematical Manual) are China’s most valuable mathematical heritage. Jiuzhang Suanshu (The Nine Chapters of Mathematics) was written about at the beginning of the Eastern Han Dynasty. There were 246 solutions to mathematical problems. In the fourth year of the Jingyuan reign (AD 263) of the Wei Dynasty, Liu Hui annotated the Jiuzhang Suanshu and theoretically proved the solution in the Jiuzhang Suanshuthe, thus establishing a theoretical system for ancient Chinese mathematics. His theories include proof of Pythagorean theorem, number system theory, area volume theory, linear equation solution, multiple difference technique, etc. Liu Hui was the first person in China who explicitly advocated the use of logical reasoning to demonstrate mathematical propositions. His work has inspired mathematicians around the world.