Why is China's calligraphy a unique art of all mankind?

China's calligraphy is an ancient art, which develops with the development of Chinese civilization. China's calligraphy has a long history, from bronze inscriptions in Oracle Bone Inscriptions to Da Zhuan, Xiao Zhuan and Li Shu to the Eastern Han Dynasty and Wei and Jin Dynasties, cursive script has been passed down for thousands of years. Therefore, it is a unique art of all mankind.