The Chinese doctor makes a diagnosis in terms of yin and yang, chi, Blood, and organ imbalance. The term Blood refers to much more than the material substance. Blood is the process of nourishing the organism; it occurs in a mutually regulating relationship with chi and Moisture (body fluids). In forming a diagnosis, the doctor is guided by the Eight Principles, which are four sets of polar categories (yin and yang, cold and heat, deficiency and excess, and interior and exterior). The Eight Principles serve as the framework for the data gathered through physical examination, tongue and pulse diagnosis, and observation of symptoms. Once the doctor forms a cohesive picture of the pattern of disharmony, he or she can formulate a treatment plan to restore balance.

The tongue is considered a sensitive barometer of human health in traditional Chinese medicine. Subtle changes in its color, texture, and coating indicate specific body imbalances and reveal the progress of the illness to the experienced doctor. The pulse, like the tongue, is also a barometer of harmony or disorder. By feeling positions on each wrist along the radial artery, the well-trained Chinese diagnostician can detect underlying imbalances in internal organs and in the body as a whole.