This book begins with the Chinese concept of the centre and the characters for the stomach and spleen. It discusses their functions as storehouses and granaries, explores their five phase resonances, and looks at earth as the source of all stability through change. The interdependent relationship between spleen and stomach is examined, along with the pre-eminence of the stomach amongst the fu. The book contains a detailed study of the spleen and stomach from the Neijing, covering the spleen's relationship with the kidneys, and the relationships with yang ming (bright yang), chong mai (the penetrating vessel), zong jin (ancestral muscle) and xu li (great luo of the stomach). A substantial appendix summarizes the functions of spleen and stomach, and selected quotations from the Neijing are given. The pathology is presented in brief with principle causes of disease.