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Mung beans (Vigna radiata) are originally substances belonging to the central earth of the Spleen. However, the skin of the mung bean is cold in nature while the flesh is neutral, thus it can reach from the interior to the exterior to resolve heat. Therefore, in the surgical formula *Huxin San* (Heart-Protecting Powder), mung bean powder is used to allow toxins to disperse outward. The world believes that mung beans can detoxify all kinds of medicinal errors, not knowing that mung beans can only suppress heat and toxins; they cannot make ingested erroneous medicines without heat and toxins vanish into nothingness.

The flowers and fruits of the Hyacinth Bean (Lablab purpureus) are white. Between the fruits, where the sprouts hide, there is another line shaped like an eyebrow, exceptionally pure white. Moreover, after the White Dew solar term, the fruits become more abundant, indicating that it obtains the most Metal Qi. All beans are sweet in taste and enter the Spleen, so they can distribute clear and肃 (solemn/clearing) commands during the summer when dampness is abundant and Spleen Qi is weak, restoring the robust and fertile Qi of the earth. This is why *Qianjin Fang* (Essential Prescriptions Worth a Thousand Gold) and *Ju Fang* (Formulas of the Imperial Medical Bureau) use the seeds for treating Huoluan (Cholera-like disease). However, its power to tonify the Spleen is extremely strong; it is suitable only when the Spleen is constrained by dampness but without abdominal pain or depression. Thus, it makes sense that *Bencao Mingyi Bie Lu* (Additional Records of Famous Physicians in Materia Medica) states that it treats continuous vomiting and diarrhea in Huoluan by attributing this effect to the leaves rather than the seeds. Huoluan involves the interference between Yin-Yang and clear-turbid Qi. When the Hyacinth Bean is in peak heat, its flowers have not yet appeared, but its branches and leaves stand tall and unyielding. These cool, shady leaves do not yield to the fierce sun, causing no harm. Used for Huoluan caused by disorder of clear and turbid Qi, it naturally allows the clear to return to clarity and the turbid to return to turbidity. Then, the record in *Tang Bencao* (Tang Dynasty Materia Medica) stating that crushing one handful of fresh Hyacinth Bean, mixing with a little vinegar, and taking the juice immediately cures muscle cramps after vomiting and diarrhea proves that *Bie Lu* is not false.

It is commonly said that staying under a Hyacinth Bean shed for cooling off can cause malaria, and some even refuse to eat the beans as vegetables. This also has reasons. The Hyacinth Bean uses its shady leaves to resist the fierce sun, and since both flowers and fruits are white, it fully possesses Metal Qi, clearly showing it does not fear summer heat. Because they do not fear each other, they contend. Malaria is a disease of contention between pathogenic factors and healthy Qi, hence the taboo. Beans obstruct Spleen Qi, how can they resolve toxicity? Zhang Zhongjing therefore stated that those suffering from alternating chills and fever should not eat them.

Dan Chi (Fermented Soybean) is recorded as bitter and cold in *Bie Lu*. Li Shi-zhen stated that Black Soybeans (*Soyae Semen Nigrum*) are neutral in nature, but become warm when made into fermented soybean. Since it undergoes steaming and fermentation, it can ascend and disperse. I privately believe that Zhang Zhongjing used it as an emetic because he took advantage of its combination with Gardenia (Gardeniae Fructus) — one warm and one cold, one ascending and one descending — considering its warm and ascending nature as primary.

*Bie Lu* states it treats irritability and restlessness (Fan Zao), but Zhang Zhongjing only used it to treat irritability (Fan), not restlessness (Zao). If irritability is accompanied by restlessness, it can occur in Yang meridians or Yin meridians: for Yang meridians, formulas like *Da Qing Long Tang* (Major Blue Green Dragon Decoction) or *Da Cheng Qi Tang* (Major Order the Qi Decoction) are used; for Yin meridians, formulas like *Si Ni Tang* (Frigid Extremities Decoction), *Gan Cao Gan Jiang Tang* (Licorice and Dried Ginger Decoction), or *Wu Zhu Yu Tang* (Evodia Decoction) are used, none of which use Dan Chi. Generally, irritability in Yang meridians requires releasing the exterior or purging downward; irritability in Yin meridians urgently requires restoring Yang. How could Dan Chi be competent for these tasks? Attributing the treatment of irritability and restlessness to Dan Chi in *Bie Lu* is indeed questionable.

Irritability (Fan) has deficiency and excess patterns: In deficiency patterns, healthy Qi is weak and pathogens have entered but not gathered, causing mental vexation and discomfort (Ao Nu); in excess patterns, pathogens block the chest and diaphragm, causing chest knotting pain. Although termed excess, it differs from the water-food accumulation in Jie Xiong (Chest Binding) syndrome, so it can be treated by inducing vomiting. This pattern involves heat without cold and is unrelated to the Kidney. The reason for using fermented soybean is that it is bitter-warm and tends to ascend/vomit, while Gardenia drains heat and descends; together they induce vomiting to remove pathogens, rather than pacifying Yin rebellion.

Zhang Shi stated that Dan Chi mainly opens Yin essence to nourish upwards, and Zou Shi then used this as evidence for treating headache in Shang Han (Cold Damage) and toxic miasma. He did not realize this leads to a discrepancy of miles due to a slight error. Initially, Shang Han and toxic miasma involve body heat but actually carry Yin pathogens internally, so Xin Wen (Pungent-Warm) formulas like Cong Chi Tang (Scallion and Fermented Soybean Decoction) for sweating, or herbs like Ren Zhong Huang (Human Middle Yellow) for detoxification are appropriate. Why would they need to nourish Yin organ essence? Moreover, how can Dan Chi open Yin essence? One can realize this by brewing and tasting Dan Chi, which induces nausea.

Dan Chi is warm, not cold, and certainly does not treat restlessness. Zou Shi was too rigid about *Bie Lu*, leading to contradictory interpretations of various formulas. Black Soybeans belong to the Kidney grain category. When steamed into fermented soybean, the intention is for it to rise directly from the Kidney. Because it is a Kidney grain capable of treating Kidney deficiency consumptive diseases, many formulas by Cui Shi in *Qian Jin Fang* use it to regulate Kidney deficiency. Because as fermented soybean it does not descend quickly, it is often crushed with Rehmannia (Rehmanniae Radix) or steamed with rice and Rehmannia. Zou Shi correctly said it pulls out Yin shadows from the lowest level. However, when explaining Cong Chi Tang, he claimed it is suitable for sudden onset difficult-to-identify conditions, yet also said it treats Heat pathogens, not Cold. He ignored Ge Hong’s (Ge Zhichuan) intent: in the first one or two days of onset, headache might suggest Cold invading the Taiyang meridian, while a surging pulse might suggest Heat emerging in the Yangming meridian. Administering Cong Chi Tang resolves the pathogen without harming Yin or Yang. It is precisely because differentiation is difficult that this excellent formula was created, and later generations widely adopted it. Adding Tong Bian (Child's Urine) after decoction is because Cong Chi is pungent-warm; adding a little Tong Bian prevents injury to Yin and harmonizes with Zang Qi. If Dan Chi were inherently cold, adding cold Tong Bian would make Cong Bai (Scallion White) also cold despite its pungency, greatly reducing its exterior-dispersing power, which contradicts formulation principles.

Zou Shi cited *Su Wen* ("When Qi is cold and cool, treat with cold and cool, perform water soaking") and commentators who interpreted "water soaking" as using hot water to soak cold herbs to treat cold conditions. He then cited formulas in *Shang Han Lun* using fermented soybean that are not boiled with raw water as conforming to "treating cold with cold." *Jin Gui Yao Lue*'s *Zhi Zi Da Huang Tang* (Gardenia and Rhubarb Decoction) boils four ingredients together without sequence, not for treating cold. Alas! Zou Shi was mistaken. The so-called commentators were likely modern scholars lacking deep understanding. According to *Su Wen*, "Qi cold" refers to the North, "Qi cool" to the West, following the previous section on Northwest Qi. "Treat with cold and cool, perform water soaking" follows "disperse and cool." The former explains principle, the latter treatment. Wang Bing noted: People in the Northwest have dense skin and pores and eat hot foods, so they benefit from dispersal and cooling. Dispersal refers to warm baths to promote smooth flow inside and out. "Perform water soaking" means immersing in hot liquid. Zhang Yinan said: Northwest climate is cold and cool, suppressing human Yang heat internally, so treat with cold/cool methods. "Perform water soaking" means using liquid immersion to induce sweat. Combining these views, "soaking" in the classic definitely refers to bathing to induce sweat, a method common in the Northwest today, not soaking cold herbs in hot water. If soaking cold herbs in hot water could treat cold diseases, drugs would be universally applicable. So, why does *Zhi Zi Chi Tang* boil other herbs first and Dan Chi last? This is similar to *Xie Xin Tang* using boiling water to soak and squeeze juice. Dan Chi, being Kidney grain, aims to ascend, so it is not boiled long. Generally, using Dan Chi to induce vomiting or sweating follows this method. For example, in *Zhi Shi Zhi Zi Chi Tang*, Dan Chi is boiled only once or twice; because Zhi Shi inhibits it, using one sheng of Dan Chi and boiling briefly is fine. *Zhi Zi Da Huang Tang* boils all four ingredients because it does not aim to vomit or sweat, so longer boiling is suitable. Dan Chi is used in larger amounts here because it is paired with Da Huang and Zhi Shi, yet still intended to act upwardly. Regarding *Gua Di San* in *Jin Gui*, it uses raw water to boil for vomiting. It uses seven ge of Dan Chi without specifying water amount, implying raw water is unlimited to exhaust Dan Chi's power. Strong flavor tends to descend. Some doubt if this contradicts vomiting methods. Vomiting retained food differs from vomiting cold fluid. Vomiting retained food should slightly inhibit its floating nature. Although inhibited, combining bitter-warm Dan Chi with bitter-cold Gua Di and sour-sweet Chi Dou ultimately激ates upward movement. Bitter-cold and sour-sweet are pounded into powder, while bitter-warm is decocted; both have ascending-descending dynamics. Thus, opposing their nature to stimulate action serves as a vomiting method. Zou Shi failed to thoroughly understand the classics and formula intents, forcing connections, thereby misleading himself and others.