The Yijing is a personal spiritual diary kept by Kenneth Goodall from 1982 until his death in 2020. It records the development and practice over several years of Yijing Gongfu, a yoga system for men based on a synthesis of Confucian moral and Daoist sexual self-cultivation exercises. The moral exercises include consultation and study of the Yijing, the ancient Chinese divination text that constitutes the foundation of Chinese philosophy. The sexual exercises are based on the teachings of the contemporary Daoist Dr. Stephen Chang in his books "The Great Tao" and "The Tao of Sexology" along with several ancient Chinese physicians' instructions unearthed in 1973 from the tomb of 168 BCE in Mawagndui, Hunan, China. In addition, Yijing Gongfu includes the Neo-Confucian meditation practice called quiet-sitting. The journal, totaling some 400 notebooks, records the author's Yijing inquiries and his interpretations of Yijing responses both at the time of inquiry and in later rereadings of the notebooks. Also recorded are the yoga's development process and the author's sexual exercise sessions. The notebooks include innumerable extracts from the author's reading of Eastern and Western spiritual texts, not only the works of such Neo-Confucian thinkers as Zhu Xi, Lai Zhide, and Gao Panlong but also the writings on self-cultivation practices by Henry David Thoreau, Sri Aurobindo, Epictetus, Ignatius de Loyola, and many others. Goodall was an American writer and editor with special interest in psychology. He began keeping the journal in 1974 after undergoing two powerful spiritual experiences that converted him to a life of solitude, voluntary poverty, celibacy, and fasting retreats in the California mountains and high desert. He began Yijing study in 1979. The notebooks for the first several years were discarded or destroyed and thus the record begins in 1982.

-written by Kenneth Goodall, edited by Katie Webber.