In this erudite yet practical book, Professor Cheng Man Ch'ing demonstrates precisely how the postures and moves of t'ai chi work, with examples from anatomy and physics, both internally as energetic principles and externally on opponents. He makes plain the spheres, triangles, and centripetal and centrifugal forces within physical exchanges such as push-hands. Contrasting Western and Chinese techniques of healing, he also explores the relationships of organs to one another in pathology and the necessary dynamics of treatment.Professor Cheng always emphasizes that disease (like an attack from an opponent) is an opportunity for training. The practitioner of t'ai chi ch'uan may serve as his or her own doctor and, likewise, as the physician or trainer of an attacker. The martial arts are not a special case of unusual power; they are simply an aspect of adapting natural and cosmic law to circumstance. At this point, philosophy itself merges with matter, physics becomes meditation, and the gravitational forces of the universe are our ally.