There were four great calligraphers in the Song Dynasty: Su Huang, Mi Cai, and Su Huang were Su Shi and Huang Tingjian. Su Shi is natural, Huang Tingjian is vigorous, Mi Fu is elegant, and Cai Xiang is subtle. Each has its own demeanor and can be called a masterpiece. The four schools of the Song Dynasty drew heavily on the heritage of the Jin and Tang Dynasties, and were determined to innovate, each with its own strengths.
From the perspective of calligraphy style, Su Shi is plump and innocent; Huang Tingjian is vertical and horizontal, high and hidden; Mi Fu is handsome and bold, calm and happy. They were all good at learning from the ancients and full of innovative spirit. Their calligraphy style was unique and highly praised by people at that time. They were listed among the four schools without any objection. It is generally believed that the so-called Cai refers to Cai Xiang (Jun Mo). His calligraphy is based on the Jin and Tang Dynasties, and pays attention to ancient meanings and laws. However, some people think it is Cai Jing. Who exactly he refers to has always been controversial.