原病式曰或言下痢白为寒者误也若果为寒则不能消谷何由反化为脓也所谓下痢谷反为脓
血如
世之谷肉果菜湿热甚则自化腐烂溃发化为脓血也其热为赤热属心火故也其湿为黄湿属脾土故
也燥郁为白属肺金也经曰诸气愤郁皆属于肺谓燥金之化也然诸泻痢皆兼于湿今反言气燥者谓
湿热甚于肠胃之内而肠胃拂郁结而又湿至于否以致气液不得宣通因以成肠胃之燥使烦渴不止
也假如下痢赤白俗言寒热相兼其说尤误岂知水火阴阳寒热者犹权衡也一高则必一下一盛则必
一
衰岂能寒热俱甚于肠胃而同为痢乎如热疮疡而出白脓者岂可以白为寒与其在皮肤之分属金故
色白
也次在血脉之分属心火故为血也在肌肉属脾土故作黄脓在筋部属肝木故其脓色带苍深至骨属
肾水故紫黑血出也各随五脏之部而见五色是其标也本则一出于热但分浅深而已大法下迫窘痛
后重里急小便赤涩皆属燥热而下痢白者必多有之然则为热明矣
按河间谓赤白不当分冷热乃属肺金心火之化又谓五色各属五脏本则一出于热其论至当但
世患
此疾者赤白居多今既以不当分冷热为治若专以辛苦寒退热此则治本之法所谓心火肺金之化者
抑有别与盖心主血肺主气白属肺金此气受病也赤属心火此血受病也赤白相杂血气俱受病也知
此则肝青脾黄肾黑之说亦可得而互明矣
《原病式》说：有人说下痢白色属于寒证，这是错误的。如果真的是寒证，就不能消化谷物，怎么会反而化为脓呢？所谓下痢中谷物反而化为脓血，就像世间的谷、肉、果、菜在湿热极盛时，自然会腐烂溃烂，化为脓血一样。其中红色是因为热，热归属于心火；黄色是因为湿，湿归属于脾土；白色是因为燥郁，燥郁归属于肺金。经典说：“各种气机愤懑郁结的病证，都归属于肺”，这是指燥金的化生作用。然而所有的泻痢都兼夹湿气，现在反而说气燥，是指湿热在肠胃内部非常严重，导致肠胃拂逆郁结，加之湿气阻滞，致使气液不能宣通，从而造成肠胃的干燥，使得烦渴不止。
假如下痢赤白相间，世俗说法认为是寒热夹杂，这种说法更是错误。要知道，水与火、阴与阳、寒与热，就像秤杆上的权衡一样，一端高则另一端必低，一方盛则另一方必衰，怎么可能寒和热同时在肠胃里都很严重而共同导致痢疾呢？比如热疮疡发出白色脓液，怎么能因为白色就认为是寒证呢？那是因为它在皮肤部分，归属于金，所以颜色白；其次在血脉部分，归属于心火，所以是血；在肌肉部分，归属于脾土，所以作黄脓；在筋部，归属于肝木，所以其脓色带苍青色；深至骨骼，归属于肾水，所以有紫黑色的血出。这些都随着五脏所属的部位而显现五色，这是表象，根本原因都出于热，只是深浅不同而已。大凡出现肛门急迫窘痛、后重里急、小便赤涩等症状，都属于燥热，而下痢白色的情况也一定多有发生，因此这显然是热证。
按察河间（刘完素）认为，赤白不应当区分冷热，而是属于肺金、心火的化生作用；又认为五色各归属于五脏，根本原因都出于热，他的论述非常恰当。但是，世上患此病的人，赤白相间的居多。现在既然以不应当区分冷热来治疗，如果专门用辛苦寒凉的药物来退热，这是治本的方法。所谓心火、肺金的化生作用，或许另有区别吧？大概心主血，肺主气，白色属于肺金，这是气受病；红色属于心火，这是血受病；赤白相间，则是气血都受病。懂得这一点，那么关于肝青、脾黄、肾黑的说法也可以由此互相阐明。
The *Yuan Bing Shi* (Treatise on the Original Causes of Disease) states: Some say that dysentery with white discharge indicates a cold syndrome; this is an error. If it were truly cold, digestion of grains would be impaired, and how could it transform into pus? The so-called transformation of grain into pus and blood in dysentery is akin to how grains, meats, fruits, and vegetables in the world naturally rot, disintegrate, and transform into pus and blood when subjected to excessive damp-heat. The redness is due to heat, which belongs to Heart Fire; yellowness is due to dampness, which belongs to Spleen Earth; whiteness is due to dryness and stagnation, which belongs to Lung Metal. The Classics state: "All conditions involving qi frustration and stagnation belong to the Lung," referring to the transformation of Dry Metal. However, all types of diarrhea and dysentery involve dampness. To claim qi dryness here implies that damp-heat is severe within the intestines and stomach, causing them to become obstructed and stagnant. Coupled with dampness blocking flow, qi and fluids fail to circulate freely, resulting in intestinal dryness and incessant thirst and irritability.
If dysentery presents with both red and white discharge, the common belief that this indicates a mixture of cold and heat is even more erroneous. Water and fire, yin and yang, cold and heat are like the beam and weights of a scale; if one side rises, the other must fall; if one prevails, the other must decline. How can cold and heat both be excessively severe in the intestines and stomach simultaneously to cause dysentery? For instance, hot sores may produce white pus; can we consider it cold simply because it is white? This is because it is located in the skin layer, associated with Metal, hence white. Next, in the blood vessels, it is associated with Heart Fire, hence blood. In the muscles, it is associated with Spleen Earth, hence yellow pus. In the tendons, it is associated with Liver Wood, hence pus tinged with bluish-green. Deep in the bones, it is associated with Kidney Water, hence purple-black blood. Each color appears according to the location corresponding to the Five Zang organs; these are the manifestations, while the root cause is always heat, differing only in depth. Generally, symptoms such as tenesmus, urgency, rectal heaviness, and dark, scanty urine belong to dryness-heat. Since white dysentery often accompanies these, it is clearly a heat syndrome.
Liu Wansu (Hejian) argued that red and white discharge should not be distinguished by cold or heat, but rather attributed to the transformations of Lung Metal and Heart Fire. He further stated that the five colors correspond to the Five Zang organs, yet their root origin is heat; his theory is highly appropriate. However, in clinical practice, mixed red and white cases are prevalent. If treatment ignores the distinction between cold and heat and solely employs pungent, bitter, and cold herbs to clear heat, this addresses the root cause. Regarding the transformations of Heart Fire and Lung Metal, there may be distinct nuances. The Heart governs blood, and the Lung governs qi. White discharge relates to Lung Metal, indicating a disease of qi; red discharge relates to Heart Fire, indicating a disease of blood; mixed red and white indicates disease affecting both qi and blood. Understanding this allows for a mutual clarification of the theories regarding Liver (green), Spleen (yellow), and Kidney (black).