My ancestors left behind a tattered book, the "Secret Art of Yin-Yang Feng Shui in Sixteen Characters" written by a predecessor of the "Mo Jin XIAOWEI". This book contains sixteen characters of dragon-seeking mantras. The "Secret Art of Feng Shui" is a branch of mathematics and divination. But what exactly is mathematics and divination? The rise of divination mostly occurred after the Qin and Han dynasties, with the "I Ching" serving as its overall guideline. Its essence does not go beyond yin-yang and the five elements, generation and overcoming transformations, all of which are branches of the "I Ching", supplemented with miscellaneous theories. Things are born with forms, forms are generated with numbers, multiplication and division are used to explore and explain, aiming to trace the source of creation, this is called mathematics. Stars, earth, clouds, and objects, predicting and guiding through observation, appear in classics. In later generations, there were superstitious transmissions that gradually lost their authenticity, but it cannot be said that ancient people had no such theories. Beyond this, the minor streams are vulgar and mixed, too numerous to name. The "Historical Records" and "Zhi" roughly categorize them as "Five Elements".