Sun's book score is indeed a compulsory course for every calligrapher, and it is actually a classic calligraphy theory article that every calligrapher must learn.
Sun's Book Score is not only a classic calligraphy theory article, but also a classic calligraphy art work with excellent writing style. Although it is also a theory of preface and incompleteness, its articles are the most mature and systematic classic calligraphy theory articles in calligraphy theory.
Its content highly summarizes and refines the essence of calligraphy theory before the Tang Dynasty, involving the copying and creation of calligraphy, calligrapher's artistic accomplishment, calligraphy aesthetics and so on. His insights are original and profound, and he basically expounded the core essence of calligraphy systematically, scientifically and profoundly. His theory plays a guiding role in the study, copying and creation of calligraphy and aesthetics, and the theoretical formation of calligraphy culture. Therefore, it is also a classic calligraphy theory masterpiece with epoch-making significance in the history of calligraphy.
In fact, since the publication of Sun Shu Pu, almost all calligraphy theory's formation has been developed and deepened around the basic theory or thought of Shu Pu. The Tang Dynasty was the peak of regular script, a watershed that calligraphy theory consciously pursued, and established the position of the Tang Dynasty in calligraphy theory.
Book notation is also very important in calligraphy art, especially cursive script. More importantly, Pu Shu is an ink painting, which retains the cursive brushwork techniques before the Tang Dynasty, especially the cursive brushwork and structural techniques represented by the two kings. Before the Tang Dynasty, there was no ink book left in the world. For example, the cursive brushwork of Chunhuating Tie and Long Live Tie is recited in Sun's Book Score.