A thirty-year-old man had suffered from epigastric pain for a long time. He was sallow and emaciated with poor appetite, yet his chest often felt as if he were full after eating. He was prescribed Jiawei Zhizhu Wan (Modified Bitter Orange and Atractodes Pill), but it proved ineffective.

The condition gradually worsened; the pain became severe, causing him to cry out loudly, audible to neighbors, leading him to attempt suicide. The physician administered Tao Ren Cheng Qi Tang (Peach Kernel and Rhubarb Decoction) as a single dose, which was taken twice consecutively. This resulted in the evacuation of approximately four or five bowls of blood stasis. For three days, he remained fatigued, weak, and unable to speak. He was instructed to consume small amounts of thin rice gruel and recuperate gradually, eventually recovering completely.

The wife of Songye Kuang, an official holding the rank of Zhangke, aged over thirty, suffered from pain radiating from the epigastrium to the chest and hypochondrium, which was milder during the day and worse at night. Her Cun (Cun position) and Guan (Guan position) pulses on both wrists were wiry, slippery, and forceful. Initially, physicians diagnosed stagnation and congealed cold, prescribing dispersing and purgative agents without effect. Subsequently, formulas such as Tieshua San (Iron Brush Powder) and Simo Yin (Four-Mortar Drink) were used, also without success. Even drinking water induced vomiting and rejection. After a month of not eating, the pain intensified further. I determined that the syndrome was clearly phlegm obstruction. However, given the prolonged pain and extreme weakness, I dared not employ the emetic method. What could be done? Accidentally, a physician suggested that Wulingzhi (Trogopterus Dung) and Moyao (Myrrh) were effective when used previously, but everyone mocked him. These herbs had been used extensively before. I said there was no harm in using them again; why mock him? That physician prepared them with wine. Upon ingestion, the patient vomited immediately, expelling approximately two bowls of green phlegm. The pain ceased instantly, and she was able to eat. This indicated that the phlegm was lodged above the diaphragm; purgatives could not remove it, so only the emetic method could cure it. As the Classic says: "When there is an excess pathogen, there will be no injury," this is precisely what is meant.

The Yellow Emperor asked: "I have heard that those who speak well of Heaven must have verification in humanity; those who speak well of antiquity must align with the present; those who speak well of humanity must rectify themselves. In this way, the Dao is not confused, and its essential principles are exhausted, which is called being enlightened. Now I ask you, Master, hoping to hear knowledge that can be known through words, seen through observation, and obtained through palpation, allowing me to verify it upon myself as if removing blindness or resolving confusion. May I hear it?" Qibo bowed twice and kowtowed, replying: "What aspect of the Dao do you inquire about?" The Emperor said: "I wish to understand sudden pain in the five Zang organs of humans; what Qi causes this?" Qibo replied: "The flow of meridians never ceases, circulating endlessly around the body. When Cold Qi enters the meridians, its flow becomes sluggish, and blood coagulates and fails to move. If Cold lodges outside the vessels, blood volume decreases; if it lodges inside the vessels, Qi circulation is obstructed, resulting in sudden pain."

The Emperor said: "This pain sometimes stops suddenly, sometimes persists severely without relief, sometimes is too painful to press, sometimes relieves upon pressing, sometimes pressing yields no benefit, sometimes pulsates under the hand, sometimes heart pain radiates to the back, sometimes hypochondriac pain radiates to the lower abdomen, sometimes abdominal pain radiates to the inner thighs, sometimes pain lingers and forms masses, sometimes sudden severe pain causes unconsciousness with recovery after a short while, sometimes pain accompanies vomiting, sometimes abdominal pain is followed by diarrhea, sometimes pain accompanies constipation. All these pains differ in form; how should they be distinguished?" Qibo said: "When Cold lodges outside the vessels, the vessels become cold, contract, and cramp. Cramping pulls on small collaterals, causing sudden pain; warmth alleviates the pain. If repeatedly attacked by Cold, the pain becomes chronic. When Cold lodges within the vessels and clashes with Warmth, the vessels become full, causing severe pain that cannot be pressed. If Cold remains stagnant and Warmth rises, the vessels swell, and Qi and Blood become chaotic, making the pain severe and intolerable to pressure. When Cold lodges between the stomach and intestines, below the membrane source, blood cannot disperse, and small collaterals tense, causing pain; pressing disperses Qi and Blood, relieving pain. When Cold lodges in the vessels flanking the spine, deep pressure cannot reach it, so pressing yields no benefit. When Cold lodges in the Chong Mai (Penetrating Vessel), the vessel becomes obstructed, Qi follows the obstruction, and pulsation is felt under the hand. When Cold lodges in the Back-Shu vessels... [omitted, see Back Pain section]. When Cold lodges in the Jueyin Meridian, which connects to the genitalia and ties to the Liver, Cold in the vessels causes blood coagulation and vessel tension, leading to radiating pain between the hypochondrium and lower abdomen. When Jue Qi lodges in the inner thighs, and Cold ascends to the lower abdomen, blood coagulation below causes mutual traction, resulting in abdominal pain radiating to the inner thighs. When Cold lodges in the membrane source and collateral blood of the Small Intestine, blood coagulates and cannot enter the major meridians; Qi and Blood stagnate, forming masses over time. When Cold lodges in the Five Zang organs, Jue Qi leaks upward, Yin Qi exhausts, and Yang Qi fails to enter, causing sudden severe pain and unconsciousness; life returns if Qi recovers. When Cold lodges in the stomach and intestines, Jue Ni (Rebellious Qi) flows upward, causing pain with vomiting. When Cold lodges in the Small Intestine, it fails to gather and transform properly, causing diarrhea and abdominal pain. When Heat Qi stays in the Small Intestine, intestinal pain occurs; intense heat causes dryness and thirst, leading to hard, dry stool that cannot pass, causing pain with constipation."