My Medical Convictions 9

How Traditional Chinese Medicine Diagnoses Diseases Using the Concepts of "Excess" and "Deficiency"

As previously discussed, the core mission of medicine is to address the issues of "excess" and "deficiency" in the human body. But how do we diagnose whether a patient is suffering from "excess" or "deficiency"?

It is common knowledge among ordinary Chinese people that Traditional Chinese Medicine (TCM) diagnoses diseases through the "Four Diagnostic Methods": inspection (Wang), auscultation and olfaction (Wen), inquiry (Wen), and palpation and pulse-taking (Qie). In ancient times, when medical examinations and laboratory tests were underdeveloped, our ancestors devised this system to assess a patient's basic condition and determine the etiology based on the body's external manifestations.

We refer to this method as "observing the exterior to know the interior" or "inferring the interior from the exterior." The key to this approach is "perceiving the subtle to understand the obvious," meaning that doctors deduce significant, systemic changes from minor, localized alterations. Frankly speaking, this is a highly challenging task, and ancient physicians were well aware that the accuracy of such judgments was quite limited.

To improve accuracy, traditional TCM requires collecting the most comprehensive information possible for a holistic assessment. This is what TCM emphasizes as "synthesizing the Four Diagnostic Methods." It stresses that when examining a disease, these four diagnostic methods must be organically integrated and comprehensively analyzed to make a thorough and accurate assessment of the condition, thereby avoiding the limitations of relying on a single diagnostic method.

Even with the synthesis of the Four Diagnostic Methods, accurately diagnosing a disease remains extremely difficult. For instance, pulse diagnosis, inquiry, and inspection may yield contradictory conclusions. During pulse-taking, a patient's pulse might indicate "deficiency," but inquiry might reveal symptoms and sensations that point to an "excess" syndrome. In such cases, reaching a definitive conclusion is highly challenging. Consequently, some doctors propose "discarding the pulse and following the symptoms," while others suggest "discarding the symptoms and following the pulse." Deciding when to apply which principle relies entirely on the individual doctor's subjective interpretation ("the physician relies on intuition"), which makes the issue exceedingly complex.

Speaking of pulse diagnosis, Wang Shuhe pointed out as early as in Mai Jing (The Pulse Classic) that doctors often experience a phenomenon where "the mind is clear, but the fingers are confused." This means that while studying pulse theory, one might feel they have fully understood it, but when actually taking a patient's pulse, they are completely bewildered, unable to determine the specific pulse type or the corresponding disease.

In fact, I am about to say something that might not only enrage hardcore TCM enthusiasts but also cause some patients to resent me. What I want to say is that the fundamental reason for this is that TCM pulse diagnosis is unreliable.

I once read Traditional Chinese Medicine and Science by Professor Jiang Chunhua, a highly respected figure in the TCM community. In the book, he mentioned that, commissioned by the Ministry of Health, he organized a scientific study on pulse diagnosis. He gathered several renowned senior TCM doctors in Shanghai and had them independently take the pulses of the same group of patients. The results showed extremely low consistency. How low was it? The proportion of identical pulse diagnosis results was only about 15%. Based on this, he concluded that pulse diagnosis was too subjective and of little research significance, leading him to shift his focus to tongue diagnosis. In reality, tongue diagnosis is just as unreliable as pulse diagnosis.

After reading his article, I gave up on in-depth research into TCM pulse diagnosis. I personally believe that investing time and energy into researching such an unreliable diagnostic technique is a waste of time. The more you study it, the more confused you become. Just think about it: every teacher has their own set of pulse theories without a unified standard. If we study TCM under multiple teachers, what will the outcome be? We will only end up with no consensus at all.

A few days ago, when discussing this issue with someone, a friend asked me on the spot, "So you don't take your patients' pulses anymore when treating them?" I replied that I do take their pulses, for two reasons:

First, there are indeed a few typical pulse types that have practical significance. For example, Jie (knotted) and Dai (intermittent) pulses are not easily misdiagnosed. These pulses exhibit regular pauses during beating, indicating heart problems. Another example is the Xian (wiry) pulse, which has a certain correlation with abnormal blood pressure. Identifying such pulses plays a role in assessing the patient's condition, and this assessment is relatively accurate. There are several other similar pulses, which I will elaborate on in a dedicated article when the opportunity arises.

Second, taking a pulse provides psychological comfort to patients, making them feel that the doctor is treating them earnestly. After all, patients are eager for treatment, and Chinese patients have a deep-rooted recognition of the TCM diagnostic methods of "inspection, auscultation, inquiry, and palpation." Doctors are often called "walking placebos." Not taking a patient's pulse would make them feel uncomfortable, thereby losing the "placebo effect."

After I personally abandoned pulse research and shifted my focus to studying objective clinical symptoms, the effective rate of my treatments increased significantly. Why is this? Because clinical symptoms lack subjectivity, making them more accurate. When using medications to treat diseases, the most crucial step is finding an accurate basis for medication. Using highly objective clinical symptoms as the basis makes it less prone to errors.

Therefore, although I quote the ancient concept of "synthesizing the Four Diagnostic Methods," I do not entirely agree with it. Personally, I lean towards not practicing this synthesis in the traditional sense. Once inquiry is combined with pulse diagnosis, it often leads to self-contradiction and misdiagnosis. However, the underlying idea of synthesizing the Four Diagnostic Methods is not wrong; doctors indeed need to collect comprehensive information to assess a patient's condition for greater accuracy. The only debatable point is whether this comprehensive information should include TCM pulse and tongue diagnosis.

To be frank, most of the time, my own pulse-taking and tongue diagnosis are merely for show, just to comfort the patients. I place more value on the highly objective information collected through inspection, auscultation, and inquiry, cross-referencing it with the patients' various Western medical test reports. This approach makes misdiagnosis less likely.

Many of my articles are quite uncomfortable to read, and this one should be no exception. I am fully aware of this. I would like to apologize and clarify in advance that these are merely my personal views. My opinions might be wrong, and I do not force anyone to agree with me.

I also have no objections to other doctors diagnosing diseases through pulse diagnosis. Perhaps some doctors have a special talent in this area and can indeed cure diseases through pulse-taking. It is just that my own skills are inadequate, and I have not reached such a high level, so I will not make reckless claims to deceive others.

As a side note, "palpation" in the Four Diagnostic Methods does not only refer to pulse-taking (commonly known as feeling the pulse); it also includes abdominal and physical examinations. Fuzheng Qilan (A Unique Guide to Abdominal Diagnosis), co-authored by Japanese Kampo medicine scholars Inaba Katsu and Wakuda Tora, provides a detailed introduction to TCM abdominal and physical examination techniques. This book has been translated into Chinese, and those interested can purchase and read it.

So, how does TCM determine whether a patient has "excess" or "deficiency" through the Four Diagnostic Methods? Here, we must mention another principle in TCM diagnostics: "evaluating abnormalities against normal standards." "Normal" refers to the usual state of a healthy person, or in TCM terminology, the state of a "Pingren" (healthy individual). "Abnormality" refers to the state of being ill.

Simply put, "evaluating abnormalities against normal standards" means using the normal state of a healthy person or the patient's baseline as a reference to judge whether the patient's current state is "excess" or "deficiency." If a patient is weaker or more depressed than normal, we call it "deficiency"; if they are stronger or more hyperactive than normal, we call it "excess."

Pulse diagnosis is the most distinctive diagnostic method in TCM. I have personally basically excluded it from my diagnostic methods; this is merely my personal inclination. For friends who wish to study TCM pulse diagnosis, you can read Chapter 19, "Treatise on the True Visceral Pulses of the Jade Machine," in the Huangdi Neijing (Yellow Emperor's Inner Canon) to learn what constitutes an "excess pulse" and a "deficiency pulse."

Additionally, there are specialized pulse works such as Wang Shuhe's Mai Jing (The Pulse Classic) and Li Shizhen's Binhu Maixue (Binhu's Study of the Pulse), which contain extensive explanations. Because I personally do not believe in the accuracy of pulse diagnosis, although I studied these in my early years, I will not offer random interpretations.

It is easy to detect abnormalities in patients through inspection, auscultation, and inquiry. However, in modern times, this is not always the case. Many patients are diagnosed with major diseases like cancer through Western medical tests but show no clinical symptoms because they are still in the early to middle stages. In such cases, how should we prescribe medication? This requires referring to the concepts of "overt symptoms" and "covert symptoms" mentioned in the section "Symptoms Are the Common Language Communicating Various Medical Systems" in this book.

However, we should not be entirely misled by modern medical theories; Western medicine is not necessarily more effective than TCM in handling patient symptoms. TCM's approach of classifying and treating various symptoms is much superior to that of Western medicine. When studying Western medicine, I found it too mechanical in this regard. Therefore, when dealing with specific symptoms, I often prefer using Chinese herbal medicine.

For example, constipation is a common symptom. TCM classifies constipation into at least three major categories: "excess-type constipation," "deficiency-type constipation," and "mixed excess-deficiency constipation." These categories have subtle differences in clinical manifestations, different accompanying symptoms, and completely different medication principles during treatment.

Western medicine does not make such fine distinctions. Upon seeing constipation, it simply prescribes laxatives (such as lactulose or glycerin enemas). This approach is sometimes effective, sometimes ineffective, and sometimes even counterproductive.

In contrast, TCM uses various purgative Chengqi decoctions (such as Da Chengqi Tang, Xiao Chengqi Tang, Tiaowei Chengqi Tang, Taohe Chengqi Tang, and Da Chaihu Tang) for excess-type constipation; various tonic formulas (such as Buyang Huanwu Tang and Renshen Yangrong Tang) for deficiency-type constipation; and formulas that integrate pathogen elimination and healthy Qi tonification (such as Zengye Chengqi Tang and Xinjia Huanglong Tang) for mixed excess-deficiency constipation. This classified treatment significantly improves the effective rate.

With even finer classification, excess-type constipation can be further divided into several subtypes. Different subtypes require selecting the most suitable formula from different Chengqi decoctions, making the treatment even more precise. For example, excess-type constipation caused by blood stasis may present with accompanying symptoms such as obvious sublingual varicose veins, skin purpura, and patient mania. Such patients should be treated with Taohe Chengqi Tang, which has both blood-activating and laxative effects, and may even need to be combined with Xiayuxue Tang.

If a doctor's research into symptoms is refined to this extent, their clinical efficacy will be excellent. This is because it approaches finding a one-to-one relationship between formulas/medications and specific symptoms. Prescribing medication in this way can be described as the most ideal evidence-based medicine model, or the precision medicine model that everyone anticipates. There is no reason for the effective rate not to be high.

Having developed to this day, TCM has accumulated a massive database of formulas and indications for Chinese herbal medicines. I often browse the 10-volume Zhonghua Bencao (Chinese Materia Medica) compiled by the State Administration of Traditional Chinese Medicine and the 8-volume Zhongyi Fangji Da Cidian (Comprehensive Dictionary of TCM Formulas) published by the People's Medical Publishing House to accumulate knowledge of herbs and formulas. I take notes, organize the herbs and formulas relevant to my research direction, and review and use them frequently. Gradually, I have accumulated my own effective medication regimens.

I also extensively read real clinical case records of TCM treatments to understand how other doctors select formulas and prescribe medications. I cross-reference these with my accumulated knowledge of formulas and herbs. When reading case records, for any unfamiliar herbs or formulas, I repeatedly consult Zhonghua Bencao and Zhongyi Fangji Da Cidian to further accumulate knowledge and deepen my impression of these herbs and formulas.

I cannot say this is the best way to learn TCM, but this method and approach align most closely with my own cognitive characteristics, making it the most suitable learning method for me. I advocate rigor, seeking truth from facts, and evidence-based reasoning. I do not like relying on pure deduction or constructing unverified new formulas based on philosophical thinking.

Because formulas formulated according to so-called theories of Yin-Yang and Five Elements generation and restriction are usually speculative, and medicine is a practical and empirical science. Using speculative formulas is not entirely ineffective; sometimes such formulations work or even work very well. However, they often turn patients into guinea pigs for newly formulated prescriptions, resulting in lower efficacy and safety, which is highly unsafe for both patients and doctors.

Since I am currently writing the general introduction section, this chapter only introduces the basic principles and will not elaborate on each specific symptom and diagnostic method. Such detailed writing will be arranged in the subsequent specific discussion section, where I will provide detailed introductions based on specific symptoms and diseases.