"Xiangshi, or mutual enhancement, means one herb acts as the main agent, while another serves as an assistant. When used together, the assistant boosts the main herb's efficacy." Zhu Yanyi scanned the room, her voice clear and steady.
"The Yellow Emperor's Inner Canon, specifically the Suwen section, states: 'The herb that treats the primary disease is the Sovereign; the one that assists the Sovereign is the Minister; the one that responds to the Minister is the Envoy.' Herbs, too, have a hierarchy of Sovereign, Minister, and Envoy.
The Sovereign herb targets the main disease or symptom, playing the leading role. Its potency is paramount, and its dosage is often the largest. The Envoy herb acts as a messenger in treatment. It not only guides other herbs to the correct meridians but also harmonizes the entire formula. In every prescription, the Sovereign is essential—the head of the group. Remember this well. Actually, the most widely used Envoy herb, one you all know very well, is licorice root."
Zhu Yanyi didn't need any notes; she continued her lecture with ease. "Since ancient times, many people believed that using licorice was merely to mask the bitter taste of other medicines. But we, who study Traditional Chinese Medicine, should know that licorice is warm in nature. It tonifies the spleen and boosts qi, clears heat and detoxifies, resolves phlegm and stops coughing, relieves spasms and pain, and harmonizes other herbs. That’s why many doctors favor it—because licorice rarely harms the body."
Her words drew laughter from the students.
Zhu Yanyi smiled lightly. "Don’t laugh. I’m serious. Today, many doctors who run private clinics often aim for 'no merit, but no fault.'
But treating illness isn't about avoiding blame. Disease harms human health. If a doctor only seeks to avoid mistakes, they are gambling with the patient's life. That is irresponsible.
As doctors, our primary goal is to restore health so people can live happily. Therefore, if any of you leave here and become 'no-fault' doctors, do not claim to have attended my lectures. I absolutely forbid my students from being merely 'no-fault' doctors. If you choose not to practice medicine, that is one thing. But if you do practice, you must be true healers who save lives from suffering."
Zhu Yanyi cleared her throat. "Alright, that was a digression. Let’s return to our topic. I mentioned earlier that herbal compatibility has seven emotions. I just discussed Xiangshi (mutual enhancement). Next is Xiangwei (mutual fear).
I said there is a Sovereign, naturally there are Ministers and Envoys. I spoke of Xiangshi; now I speak of Xiangwei. What is Xiangwei? It means the toxic side effects of one herb are suppressed by another. For example, Pinellia fears fresh ginger. Fresh ginger can suppress the toxicity of Pinellia. Raw Pinellia can irritate the throat, causing pain and hoarseness. But when processed with ginger to become ginger-processed Pinellia, its toxicity is greatly reduced. This is a classic example of Xiangwei compatibility."
Zhu Yanyi looked up at the crowd. "In many modern Western medicines, there are minor side effects that many people ignore, assuming they will fade over time.
But in Traditional Chinese Medicine, we must understand the nature of the herbs first. We use another herb to eliminate the side effects of the first, ensuring the patient suffers no adverse reactions. This is Xiangwei. Simply put, using a literary idiom, it is 'suppressing evil and promoting good.'"
Zhu Yanyi continued, "The fifth of the seven emotions is Xiangsha (mutual killing). Hearing the word 'kill,' you might think it’s bad. But you are mistaken. If Xiangwei is about suppressing side effects, then Xiangsha is about eliminating them.
Xiangsha means one herb can neutralize the toxicity of another. For instance, sheep blood neutralizes the poison of Gelsemium; Jin Qian Cao neutralizes the poison of Tripterygium.
There is no qualitative difference between Xiangwei and Xiangsha. They are just two different ways of describing the same compatibility relationship: one focuses on having one's own toxicity suppressed by another, while the other focuses on one's ability to eliminate another's toxicity."
The students were now fully engaged, their attention peaked.
"The sixth emotion is Xiangwu (mutual antagonism). I once heard an ancient story. A wealthy family took in a cousin girl whose parents had died. She inherited a vast fortune, so she lacked for nothing. However, she was frail and drank ginseng soup year-round. We know today that drinking ginseng daily can cause illness even in healthy people, but let’s ignore the logic of the story.
The point is, this cousin girl drank ginseng soup. Her relatives treated her well, giving her the best food and never stopping her ginseng. Yet, within three or five years, she died. Her fortune went to the family. In truth, the family had bribed the maid who prepared the medicine to add radish seeds to the ginseng soup."
Zhu Yanyi looked at the class and smiled. "Do you know what radish seeds are?"
The students exchanged glances and shook their heads.
"Radish seeds are the dried, mature seeds of the radish. In Chinese medicine, they are called Laifuzi, a pleasant-sounding name. They aid digestion, relieve bloating, descend qi, and resolve phlegm. However, when combined with ginseng, they weaken ginseng’s ability to tonify qi. This is Xiangwu. Theoretically, Xiangwu means one herb destroys the efficacy of another.
Just like in the story, adding a few radish seeds to ginseng over years killed a person." Zhu Yanyi said calmly. "Of course, this is just a story. I am not teaching you to use herbs to kill people. If I did, I would be a sinner for eternity."
Zhu Yanyi joked about the danger of Xiangwu. "Don’t blame me for being scary. There are many such antagonistic pairs in Chinese medicine.
Everyone knows about 'food incompatibilities.' This is a typical example of Xiangwu.
For instance, eating tofu and honey together can cause deafness. Eating kelp and pig blood together can cause constipation. There are many such examples in Chinese dietary culture."
She added, "Some might say, 'Zhu Yanyi, you are talking about food, not medicine.' I want to say that in Chinese culture, food is medicine. We just call daily edible herbs 'food.'
Edible medicine is simply called food. For example, rice. Rice is food to fill your stomach. But do you know that rice can be paired with five flavors and provides almost all the nutrients the body needs?"