问曰∶手足心腋下有汗，何以是阳明腑病？答曰∶胃主四肢，为津液之主，今热聚于胃
致令出汗，乃津液之旁流也。经云∶手足 然汗出，大便难而谵语，宜下之。又问曰
∶阳明中寒，不能食，亦令手足汗出者，何也？答曰∶此胃中虚冷所致，与传经热证，便难
谵语者，自是不同。
问曰∶便闭何以属阳明腑证？答曰∶阳明居中土也，万物所归，无所复传，伤寒三阳、
三阴之邪，皆得传入，以作胃实不大便之证，法当下之。然经有八禁，详例于前，不可不辨
问曰∶转矢气，何以属阳明腑证？答曰∶矢气者，气下泄也，病患内有燥粪，结而不通
则气常下失。仲景云∶欲行大承气，先与小承气，腹中转矢气者，方与大承气汤；若不转
矢气，慎未可再攻，是知转矢气，属阳明腑也。
伤寒之邪，三阳为表，三阴为里，人皆知之，而里中之里人所不知也。何谓里中之里？
阳明胃腑是也。三阳、三阴之邪，一入胃腑，则无复传，故曰里中之里也。或谓三阴经，脏
也。阳明胃，腑也。岂有腑深于脏者乎？答曰∶阳明居乎中土，万物所归，无所复传，犹之
溪谷，为众水之所趋也。夫以阳经与阴经较，则三阴为深；以阴经与胃腑较，则胃腑为尤深
也。三阳、三阴之经，环绕乎胃腑，处处可入。有自太阳入腑者，有自本经入腑者，有自少
阳入腑者，有自太阴入腑者，有自少阴入腑者，有自厥阴入腑者，一入胃腑则无复传，故曰
里中之里也。治伤寒者，先明传经、直中，即于传经之中，辨明表里，更于表里之中，辨明
里中之里，如此则触目洞然，治疗无不切中矣。
Q: Why is sweating on the palms of the hands, soles of the feet, and axillae (armpits) considered a disease of the Yangming Fu-organ?
A: The Stomach governs the four limbs and is the master of Jin-Ye (body fluids). Now, heat gathers in the Stomach, causing sweating; this is the lateral flow of body fluids. The Classics state: "Sweating from the hands and feet with difficulty in defecation and delirium are suitable for purgation."
Another question: When Yangming is affected by cold, leading to an inability to eat, it also causes sweating on the hands and feet. What is the reason for this?
Answer: This is caused by deficiency-cold in the Stomach, which is naturally different from heat syndromes transmitted via channels (characterized by difficult defecation and delirium).
Q: Why is constipation attributed to a Yangming Fu-syndrome?
A: Yangming resides in the central Earth element, where all things return and no further transmission occurs. Pathogens from the Three Yang and Three Yin channels of Shanghan (Cold Damage) can all transmit here, forming a syndrome of gastric excess and inability to defecate; the treatment method should be purgation. However, there are eight contraindications in the Classics, detailed in previous examples, which must not fail to be distinguished.
Q: Why is passing flatus (Zhuan Shi Qi) attributed to a Yangming Fu-syndrome?
A: Zhuan Shi Qi refers to the downward discharge of gas. If the patient has dry feces inside that are knotted and obstructed, gas often leaks downward. Zhang Zhongjing said: "To administer Da Cheng Qi Tang, first give Xiao Cheng Qi Tang. If the abdomen rotates and passes flatus, then give Da Cheng Qi Tang; if there is no passing of flatus, be cautious and do not attack again." Thus, we know that passing flatus belongs to Yangming Fu-disease.
The pathogens of Shanghan consider the Three Yang as exterior and the Three Yin as interior; everyone knows this, but the "interior within the interior" is unknown to people. What is meant by "interior within the interior"? It is the Yangming Stomach Fu-organ. Once pathogens from the Three Yang and Three Yin enter the Stomach Fu, they cease to transmit further, hence it is called the "interior within the interior." Some argue: The Three Yin channels correspond to Zang-organs, while Yangming Stomach corresponds to a Fu-organ. Can a Fu-organ be deeper than a Zang-organ?
The answer is: Yangming resides in the central Earth, where all things return and no further transmission occurs, similar to how valleys are the convergence point for many waters. Comparing Yang channels with Yin channels, the Three Yin are deeper; comparing Yin channels with the Stomach Fu, the Stomach Fu is even deeper. The meridians of the Three Yang and Three Yin surround the Stomach Fu, entering from everywhere. Some enter the Fu from Taiyang, some from their own channel, some from Shaoyang, some from Taiyin, some from Shaoyin, and some from Jueyin. Once entering the Stomach Fu, there is no further transmission, hence it is called the "interior within the interior." Those who treat Shanghan must first clarify channel transmission and direct invasion, distinguish between exterior and interior during transmission, and further distinguish the "interior within the interior" amidst the exterior and interior. In this way, one will see clearly at a glance, and treatments will hit the mark without fail.