Introduction
Calligrapher Liu Jiekuan writes: "There are few true scholars in the world; many are the unsatisfactory things in life, both past and present." There are very few people in the world who can truly read and understand the principles within books, while the unsatisfactory events in life have been numerous since ancient times. Source: Song Dynasty, Liu Kezhuang, "Complete Works of Mr. Houcun," Volume II, Fourth Series of Collected Editions by Jing Old Manuscript.