Tan Qiao's "Book of Changes" is a book recommended by Mr. Nan Huaijin in his speech. This book is a thin volume and the language is relatively easy to understand. Good use of metaphors, very vivid. There are many places in the book that are inspiring and worth savoring. To give a brief example: "Wandering clouds have no quality, so the five colors are embedded, and the mirror is flawless, so all things are like." This is the Taoist understanding of the nature of mind, which is consistent with the Sixth Patriarch Huineng's "Bodhi has no tree, and the mirror is not a stand, and it is empty. "If there is nothing, how can we stir up dust?" It is similar to what Mr. Ji, a disciple of Mr. Yangming, said: "The heart of a sage is like a bright mirror, and the heart of an ordinary person is like a dark mirror. It is like using a mirror to observe things." "Looking at things, you have to work hard on them, but you don't know that the mirror is dim, so how can you illuminate them?" The teacher's investigation of things is like polishing a mirror to make it clear.