病有不能顺治，可逆治。
有人苦头眩，头不得举，目不得视，积时年许。先生视之，使悉解衣倒悬，令头去地一、
二寸，濡布拭身体，令周匝，候视诸脉尽出五色。乃令弟子数人，以钺刀决脉，五色血尽，
视赤血出乃下。以膏摩，被覆，汗出周匝，饮以葶苈犬血散之立愈。此即逆治之法也。（孙
思邈注）
冷浴生大热。
有妇人久病经年，世谓寒热交往病。冬日十一月中，先生令坐石槽中，以寒水汲灌之，
云当满百。始七八灌，战欲死，灌者亦惧而欲中止。先生令满数，至将八十灌，热气乃蒸出，
嚣嚣高二、三尺，满百灌，乃令燃火温床浓覆，良久汗洽出，着粉汗糁便愈。按∶冷浴有反
激之力，初极冷，继极热，足以清毛管，出廉料。有经络肌肤为寒湿所困，不能发汗者，冷
浴最效。余体肥，从不服表剂，不适则冷浴，浴后辄觉肌畅神爽，始信仙方不欺人也。惟体
弱者不宜冒昧行之，违之则有损。又冷浴之后，宜用干布揉擦，斯不可不察耳。（孙思邈注）
物生于土，土燥物枯，可掘而润之，据此可以治脾。
一人病腹中半切痛，十余日中，须眉堕落，先生视之曰∶“此脾半腐也，宜刳腹，施以
洗伐。”即饮以药，令卧，破腹视脾，半腐坏，刮去恶肉，以膏敷创，饮之药，百日而平复。
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Diseases may be treated by contrary methods when they cannot be treated by following the disease's trend.
A person suffered from severe dizziness, unable to lift his head or look around, for over a year. The Master examined him and instructed him to undress completely and hang upside down, with his head positioned one or two inches above the ground. He then wiped the patient's entire body with a damp cloth until it was thoroughly moistened, waiting for the various pulses to display five colors. Subsequently, he ordered several disciples to pierce the blood vessels with an axe-like knife. Once the blood of the five colors had drained completely and bright red blood began to flow, the patient was lowered. Ointment was massaged onto the skin, the patient was covered with blankets until profuse sweating occurred throughout the body, and he was administered Tingli Quanxue San (Descurainia Seed and Dog Blood Powder), resulting in immediate recovery. This is the method of contrary treatment. (Commentary by Sun Simiao)
Cold bathing can induce high fever.
A woman had been ill for years, a condition known as alternating cold and heat. In mid-winter during the eleventh lunar month, the Master instructed her to sit in a stone trough while cold water was poured over her repeatedly, specifying that this should be done one hundred times. After only seven or eight applications, she trembled violently as if near death, and the attendants were afraid and wished to stop. The Master insisted on completing the prescribed number. By the time nearly eighty applications had been completed, internal heat began to steam out, rising two or three feet high. After one hundred applications, fire was lit to warm the bed, which was then heavily covered. After a long period, profuse sweating ensued. After applying powder to the sweat, she recovered. Note: Cold bathing has a counter-irritant effect; the initial extreme cold followed by extreme heat is sufficient to open the pores and expel metabolic waste. For conditions where meridians and muscles are constrained by cold-dampness, preventing sweating, cold bathing is most effective. I have a robust physique and never take diaphoretic formulas; when unwell, I use cold bathing, after which I always feel my muscles relaxed and spirit refreshed. Only then did I believe these immortal prescriptions do not deceive people. However, those with weak constitutions should not attempt this rashly, as doing so causes harm. Furthermore, after cold bathing, one should rub the body with a dry cloth, a detail that must not be overlooked. (Commentary by Sun Simiao)
All things are born from Earth; if the soil is dry, things wither. One can dig the earth to moisten it; based on this principle, the Spleen can be treated.
A man suffered from severe cutting pain in the abdomen for more than ten days, during which his beard and eyebrows fell out. The Master observed and said, "This is half-rotten Spleen tissue. It is necessary to perform laparotomy and cleanse the area." He immediately administered medicine, laid the patient down, performed a laparotomy to inspect the Spleen, found half of it rotten, scraped away the necrotic flesh, applied ointment to the wound, and administered further medication. The patient recovered fully after one hundred days.