In TCM Pattern Differentiation, What Matters Most Is Distinguishing a Formula's Indications

Professor Hu Xishu wrote a short essay titled "On Formula Patterns." The essay is concise and to the point, and captures the crux of TCM clinical practice. Old Master Hu said: "In TCM pattern differentiation, we do not differentiate only the six meridians and eight principles; more importantly, we must use them to distinguish the indications of formulas and herbs... The indication of a formula is abbreviated as the 'formula pattern' (fang-zheng). The indication of a given formula is called the pattern of that formula—for example, Guizhi Tang pattern, Mahuang Tang pattern, Gegen Tang pattern, Da Qinglong Tang pattern, Chaihu Tang pattern, Baihu Tang pattern, and so on. The formula pattern is the continuation of six-meridian and eight-principle differentiation; it is the very cutting edge of differentiation. Whether TCM treatment works depends crucially on whether the formula pattern is correctly identified. However, identifying formula patterns is not as simple and obvious as six-meridian and eight-principle differentiation; one must carefully study and memorize the specific pattern and treatment of each formula."

In another essay, "On the Unique Theoretical System of the Shanghan Lun," Old Master Hu said: "Pattern differentiation and treatment describes the TCM method of using herbs to treat disease; it is also often called 'syndrome differentiation and treatment.' I think 'pattern differentiation and treatment' is more plain-spoken. After all, if there is such a pattern, use such herbs—why need to quote classics and argue at length? In the old society, to be read by the wealthy gentry and to appear scholarly, making it easier to sell one's skills and beg for a living, that pitiable posture is no longer necessary."

Old Master Hu was one of the rare clear-headed figures in the TCM world; he saw the long-standing abuses of TCM over thousands of years. TCM has fallen into abstract speculation, and the more it talks, the more abstruse it becomes. The root cause is that physicians, within a Confucian cultural circle where 'excellence in study leads to office,' have historically held little status or dignity. When wealthy families invited physicians to treat illness, the physicians had to please them by learning to speak medicine in the Confucian literati's jargon in order to earn a living. Over time this became the fashion; the root of TCM healing was forgotten, and TCM was kidnapped by the nearly fantastical theory of yin-yang and the Five Phases. TCM gradually drifted further from practice. By the logic of yin-yang and the Five Phases, almost no disease would be untreatable—but in reality disease is not so easy to cure. The result was that TCM physicians talked bigger and bigger, while clinical results grew less and less satisfactory, making TCM appear extremely dishonest.

This is true not only in China but also in places influenced by Chinese culture, such as Japan. As a result, famous Japanese kampo physicians also had to package themselves in Confucian culture. Even a towering figure of kampo medicine like Asada Sohaku had to rely on Confucianism to raise his status, because everyone felt that medical skill was merely a trivial craft and Confucian learning was what was truly great. Most unknown TCM physicians in ancient China, like peddlers with rattling bells, had to walk the streets ringing hand-bells to drum up business. Such physicians were commonly called bell physicians; their social status was very low, and scholars were ashamed to sink to being bell physicians. To win trust and earn a living, bell physicians had to curry even more favor with Confucianism.

What is most closely tied to clinical efficacy are the formula pattern and the herb pattern—and these are also the hardest parts of TCM to learn. To master them, one must put in hard work memorizing a vast body of formula-herbal knowledge. The so-called theories of yin-yang, the Five Phases, the six meridians, and the eight principles can be discussed glibly by any reasonably bright scholar after a month of study. But formula patterns and herb patterns are innumerable and tangled; mastering them requires extraordinary effort. To skillfully treat patients by formula and herb patterns in the clinic requires even harder work, integrating study and reflection.

There are four or five hundred commonly used Chinese herbs, plus various less common medicinal herbs, totaling about 17,000 species. As for historically effective formulas, there are no fewer than 100,000. Flipping through the Zhongyao Da Cidian (Great Dictionary of Chinese Materia Medica) and the Zhongyi Fangji Da Cidian (Great Dictionary of TCM Formulas), one realizes that it is impossible for a TCM physician to learn all the indications and contraindications of these herbs and formulas. In the future, with AI assistance, it may be possible; relying on the human brain alone, one can only learn a limited portion. TCM physicians should therefore be realistic: mastering the treatment of one specialty's diseases and memorizing the indications of three to five hundred commonly used herbs and one or two thousand formulas in that specialty is already remarkable. The yin-yang and Five-Phase theories that can be crammed in a month or two only produce a batch of talkative pseudo-TCM practitioners.

Where did TCM formula patterns and herb patterns come from? Were they invented by sages? Of course not. Huangdi, Qibo, Yi Yin, Shennong—these were merely tiger-skin banners ancient people flaunted to bolster their own prestige, and those banners remain tools for physicians to beg a living. The ancients vividly summarized this as "borrowing the mouths of sages to establish teachings." Huangdi was busy ruling the state; how could he have so much time to study medicine? As Professor Hu Xishu put it, TCM formula patterns and herb patterns are "a great achievement gradually accumulated by the broad laboring masses in their long struggle against disease. They have a long historical development process and absolutely were not—and could not have been—created by any single era, much less by any single person."

China has always had a tradition of superstition and worship of authority, in both politics and academia, which is why China's social system and scientific-technological progress have been so slow. This is intellectual laziness: people are unwilling to explore new things or use their own minds to find new ways, preferring to live under the halo of the sages. Whether the truths uttered through the mouths of sages are right or wrong has already become unimportant.

Most so-called TCM fans influenced by TCM culture have also ruined themselves in this way of thinking. I often meet patients who open by asking me, "I have spleen deficiency; what medicine should I take? I have upper heat and lower cold; what medicine should I take?" Some patients, having read a few TCM books, even discuss their condition with me in an arrogant tone. It is hard for me to explain to each of them one by one that this way of seeking medical care is extremely foolish. The most important thing is to honestly describe one's symptoms to the physician and detail one's suffering.

In ancient times, physicians lacked today's advanced diagnostic equipment and could judge which herb to use only from the patient's oral account and the simple examinations the physician could perform. Precisely because of this, traditional medicine accumulated extremely rich and reliable data on "formula patterns" and "herb patterns." These are the very essence of TCM and what Professor Hu Xishu called "the cutting edge of differentiation." At the present stage, when modern medicine is not yet advanced enough to solve every problem, TCM "formula patterns" and "herb patterns" can make up for modern medicine's shortcomings: they can solve the patient's problem without necessarily knowing the true cause.

For example, suppose a patient tells the physician, "I sweat easily, I fear wind and feel cold, and I have a headache." An experienced physician can immediately recognize this as the Guizhi Tang pattern and prescribe Guizhi Decoction directly, solving the patient's problem. The physician may not know the true cause, yet by using TCM "formula patterns" the problem is successfully resolved. If instead the patient describes himself as "yang-deficient, weak, and prone to sweating," the physician will be bewildered and not know how to prescribe.

As early as the Han dynasty, a clinician like Zhang Zhongjing advocated the principle of "treating according to the pattern." In Zhang Zhongjing's Shanghan Lun and Jingui Yaolue, the overwhelming majority of the text describes "formula patterns" and the contraindications of each formula: which formula to use when a certain symptom appears, which patients cannot take which formula, and the insistence that the physician "must always know this and never err." This tightly interlocked description of formula and pattern has extremely strong practical value. If one tries to detach from formula patterns and herb patterns and elevate the principles of TCM treatment to the level of philosophical speculation, one commits absurdities and cannot guide clinical practice.

Take stroke, for example. We now know it is a cerebrovascular lesion caused by cerebral hemorrhage or cerebral infarction. If rescue is timely, most patients with cerebral hemorrhage can be saved by craniotomy and drainage, and most with cerebral infarction by thrombolysis. But how did ancient TCM discuss stroke?

Liu Wansu, in his Suwen Xuanji Yuanbing Shi, said: "When a person gets wind disease, it is not caused by external wind invading, but by improper recuperation: heart fire becomes explosively exuberant, kidney water becomes deficient and decayed and cannot control it; thus yin is deficient and yang is replete, hot qi becomes depressed, the heart-mind is clouded, sinews and bones cease to function, and the person falls suddenly unconscious." Li Dongyuan said: "The yang qi is named after the swiftest wind of heaven. This stroke is not an external wind evil but a disease of the original qi itself. Whenever a person passes forty and qi declines, or when worry, joy, anger, or rage injures the qi, this disease often occurs; it is absent in vigorous youth. The treatment is to harmonize the zang-fu and unblock the meridians, which is how one treats wind." The Lingshu Jing says: "When the foot Yangming and hand Taiyang sinews are tense, the mouth and eyes become twisted."

Although some of these descriptions fit features of stroke—for example, that stroke mainly affects people over forty—they are utterly unrelated to the true pathology of stroke. Using them to guide clinical practice naturally yields poor results. So much so that the famous Qing-dynasty physician Xu Lingtai said that the physicians of his day treated stroke patients one by one to death, with not a single survivor. Likewise, according to Xu Lingtai, TCM treatment of true "ye ge" (today's cardiac carcinoma or esophageal cancer) was also one by one fatal—"not one in a hundred survived"—again because the explanation of the pathology of "ye ge" was completely wrong.

But with today's medical resources, neither TCM nor Western medicine treats "stroke" or "ye ge" with one-by-one fatal outcomes. With the progress of medicine, today's physicians have recognized that the ancient TCM classics' explanations of the causes of these diseases were wrong; they have corrected that cognitive bias and, based on new understanding, readjusted treatment strategies, so efficacy has improved considerably.

Ancient TCM also had formulas for stroke, such as Xiao Xuming Tang, Hou Shi Hei San, Tongguan San, Kaiguan San, Qianzheng San, and Da Dingfeng Zhu. Each has its indications and contraindications; if used strictly according to those indications and contraindications, they are still effective.

So those who study TCM today should focus on learning formula patterns and herb patterns. In the past, TCM emphasized the sequence "principles, methods, formulas, herbs," regarding "principles" as most important and formulas and herbs as secondary. We cannot say this view is wrong, but it is an indisputable fact that many TCM "principles" are wrong. In that case, guiding clinical practice by the sequence of principles-methods-formulas-herbs yields poor results; guiding it by formula patterns and herb patterns works better. Contemporary TCM workers have an obligation to correct the errors of ancient TCM and to find the truly scientific "principles" for TCM clinical efficacy, rather than remaining complacent or even defending TCM through abuse.