Chinese Diagnostics is guided by TCM theory. It investigates the relationship between humans and environmental conditions. In ancient Chinese philosophy, “the universe and the body are one”; “every part of a human body is an organic connected whole.” So, all human diseases relate to the nature of the environment or universe. Therefore, “a part reflects the whole” and “inspect the exterior to exam the interior.” Holistic integrity or overall analysis is a TCM diagnosis technology and principle, and includes: part vs. whole, exterior vs. interior, tangible vs. intangible, and differentiation of syndromes.
The dynamic “function state” of a group of symptoms reflects the body’s reaction to exterior physical, chemical, and biological changes. Symptoms constantly change and may not be testable, measurable, or simulated in lab animal research. Subtle, interrelated, and constantly changeable symptoms, such as chest distress, heart-throbbing, headache, dizziness, fatigue, nausea, poor appetite, physogastry, shortness of breath, and kidney Yang or Yin deficiency syndrome, may call for or be uncovered by tests for a particular disease in CWM. In TCM these dynamic symptoms are the real evidence and form the Zheng (
, group of symptoms) of the dynamic function state 
of the whole body, and are not equivalent to the “infection focus” of CWM.
CWM’s infection focus examines the external expression of diseases, and recognizes structural damage by reductionism. Because sometimes TCM’s syndrome or symptoms may be seen earlier than the infection focus, TCM can be a preventive alert to problems or hint at treatment. Humans have a capacity to self-report physical and mental conditions and reactions. In some cases, this information reported in the context of the doctor–patient relationship may be more sensitive and direct than instrument tests. TCM recognizes and utilizes these unique advantages.
TCM usually treats disease as a dynamic, temporary state, and uses “accumulation,” “conglomeration,” “soft or hard” and “lumped or scattered” to characterize the disease status and the corresponding treatment. Patients can recognize subtle changes in their bodies, and the TCM physician can address the problem at all stages. At an early disease stage, it is often much easier to treat a disease by restoring physiological balance. TCM’s major advantage is for the “future disease” (in the very early stage) treatment or in disease prevention. This benefits the sub-healthy, or patients who have difficult, complicated diseases. In many cases, TCM can complement or supplement mainstream CWM.
Tongue examination, pulse-taking, and patient attitude observation are trustworthy approaches that separate TCM from CWM. The TCM technique incorporates intuitive wisdom, a multivalued logic derived from Fuzzy System theory (approximate rather than precise reasoning widely used to deal with very complicated macroscopic systems). A good TCM physician may diagnose a liver problem before lab tests show an abnormality, because TCM diagnostic techniques are highly sensitive to internal changes at a microscopic level. A TCM physician may easily guide patients to a normal status.