The Eight Guiding Principles (ba-gan)

diagnostics

The Eight Principles are a comprehensive framework that synthesizes the findings of all four diagnostic methods. These are four pairs: external–internal (where the disease is located), cold–heat (its nature), deficiency–excess (the balance of forces between the body and the pathogen), and yin–yang (a generalizing pair that unites the others). By determining the syndrome’s position along these axes, the physician obtains the “framework” of the diagnosis, from which the principle of treatment follows: external cold-fullness is treated differently than internal heat-emptiness. This is the foundational level, upon which more detailed systems (zang-fu, the six levels, etc.) operate.