4. Deficiency-Excess

4. Deficiency-Excess

Deficiency of righteous qi is deficiency, while invasion of pathogenic qi is excess; the basic meaning of deficiency-excess is the relationship between the strength of pathogenic and righteous qi. Constitution varies in strength, pathogenic factors vary in intensity, and treatment differs between tonifying and purging. The purpose of distinguishing deficiency from excess is to determine the correct therapeutic principle. Whether to attack or to tonify depends entirely on the distinction between deficiency and excess. "Purging when excess, tonifying when deficiency"—if the distinction is wrong, even a slight error can lead to a huge deviation; "tonifying deficiency, purging excess" is a major taboo for physicians.

(1) Clinical Manifestations of Deficiency and Excess

Anyone with deficiency of righteous qi or imbalance of yin and yang qi and blood falls under the category of deficiency syndrome. Causes of deficiency include congenital weakness, inadequate post-illness recuperation, or prolonged illness without proper treatment. Congenital weakness is mostly attributed to the kidneys, while acquired deficiency is mostly due to the spleen. From a modern medical perspective, so-called deficiency syndromes generally refer to the decline of physiological functions; of course, apart from congenital decline, most cases are due to prolonged illness or lack of recovery after illness. The most common clinical manifestations of deficiency include emaciation, low voice, poor appetite, fatigue, blurred vision, hearing loss, pale and swollen tongue, and a weak, fine pulse. Within deficiency syndromes, there are broadly divided categories such as qi deficiency, blood deficiency, yin deficiency, and yang deficiency. Qi deficiency includes spleen qi deficiency, kidney qi deficiency, and lung qi deficiency; blood deficiency includes heart blood deficiency and heart-spleen dual deficiency; yin deficiency includes lung yin deficiency, kidney yin deficiency, and liver-kidney yin deficiency; yang deficiency includes spleen yang deficiency, kidney yang deficiency, spleen-kidney yang deficiency, and heart yang deficiency. In recent years, there have been numerous reports on spleen yin deficiency and liver yin deficiency, and specialized monographs have even been published. These deficiency syndromes related to the zang-fu organs will be discussed in detail in zang-fu pattern differentiation. Anyone with excessive pathogenic qi, where pathogenic qi fiercely battles righteous qi, falls under the category of excess syndrome. The fundamental cause of excess is the conflict between righteous and pathogenic qi. When the body is strong, ordinary pathogenic qi cannot cause illness; when the body is weak, ordinary pathogenic qi can indeed cause illness, but the resulting diseases are mostly deficiency syndromes. If pathogenic qi is strong and righteous qi is weak, the resulting illnesses are also mostly deficiency syndromes; only when both pathogenic and righteous qi are strong does the conflict become an excess syndrome. Clinical manifestations of excess include high fever and thirst, dry and hard stools, short and red urine, coarse breathing and loud voice, abdominal pain with refusal to press, fever and chills without sweating, mental excitement, and a large, powerful pulse. In short, during excess, physiological functions exhibit pathological hyperactivity, pathogenic qi is strong, and the body's resistance to disease is also robust.

(2) True vs. False Deficiency and Excess

"The Inner Canon" says, "Great excess may show signs of deficiency, while extreme deficiency may show signs of excess." Zhang Jingyue said, "Extreme deficiency may paradoxically show signs of excess, while great excess may paradoxically show signs of deficiency—this must be carefully distinguished. For example, if a disease arises from emotional disturbances, overeating or starvation, fatigue, alcohol or sexual indulgence, or congenital deficiency, and then manifests as fever, constipation, bloating, delirium, or pseudo-rash, it may initially seem like an excess condition, but in reality, it is a deficiency. Similarly, if external pathogenic factors are not eliminated, latent pathogenic factors remain in the meridians, food stagnates and accumulates in the zang-fu organs, or qi becomes stagnant and unresolved, or stubborn phlegm and blood stasis linger, leading to prolonged illness and apparent deficiency, yet the root cause is actually excess—such cases require treating the root cause rather than being misled by superficial symptoms." The distinction between true and false deficiency-excess follows the same principle as the distinction between true and false cold-heat: whenever encountering such situations, a comprehensive analysis should be conducted, considering factors such as the strength of the constitution, the duration of the illness, careful examination of the symptoms, and detailed pulse diagnosis, to distinguish the genuine from the spurious and retain the truth.

II. Zang-Fu Pattern Differentiation

Pattern differentiation based on the zang-fu organs is what we call zang-fu pattern differentiation. It is an important component of TCM pattern differentiation and treatment, and serves as the primary method for diagnosing internal injuries.