This book has three sections: The Temporal and Spatial Backgrounds of the Book of Changes, Full Explanations of Zhou Yi’s 64 Hexagrams, and Health Preservation on the Principle of Heaven and Man As One. It explains the origin and meaning of the River Map, the Luo Writing, the Eight Trigrams, and the 64 Hexagrams, and the close relationship between medical science and the Book of Changes in an easy-to-understand way.