汪明珠After reading this book, I found that there is the same sentence in the preface and postscript of the reissue: This is not a finalized manuscript, nor can it be said to be a finished manuscript, it is just a record of attempts. This sentence is indeed in place, theoretical innovation will never be finalized, or even finalized. People should have the spirit of continuous exploration throughout their lives. Fei’s tireless spirit of theoretical innovation, quality and truth-seeking, and his practical and exploratory spirit also deeply moved me. His academic spirit of modesty, seriousness, pragmatism, and the courage to march into unknown fields also taught me.