What is the theoretical work about Guqin performance aesthetics?

As the name implies, The History of Qin is a historical work about Qin. The first five volumes of this book contain the stories of 156 people related to Qin from ancient times to the present in chronological order, and the last volume is a discussion of the theoretical laws of Guqin. The ethos is "responding to the law", "interpreting the string", "being clear", "imitating the image", "commenting on the tune", "singing the melody", "writing the story" and so on.

The last volume of Qin Shi, the interpretation of strings, lightness, likeness, pan-system and perfection, all involve the specific production of guqin. The article "The Beauty of Perfection" holds that the first step for a saint to make a utensil is to distinguish among all things and choose the most suitable material. When making guqin, Fu should have been screened and tested repeatedly. He chose phoenix tree among all the trees, thinking it was the best material for making guqin. Then he chose a tree with good quality among phoenix trees, and also paid attention to cultivating it for later use.

The ancients also believed that the material of guqin was closely related to its growing environment. The article "Qin History Perfect" holds that the truly excellent guqin materials must be hidden in the mountains and winding valleys, which is very difficult to obtain. Indus, the material of guqin, grows in a dangerous and secluded place, and its natural gas must be supreme; Thunder, sleet, floating pressure on the plane tree, and the sound of rare birds perching on the plane tree can make the plane tree feel a sad voice; And clouds and fog, zero dew and wind nourish and nourish it, making it deep and heavy.