凡伤寒热病传经之邪。比杂病不同。必辨其脉、症、舌、表里汗下之。庶不有误。况脉者，血之腑。属阴。当其得
病之初，正气相抟。若真气未衰。脉必滑数而有力。病久热甚气衰。脉必微细而无力。方数而甚也。但可养阴退阳。此
识脉之要也。或初病即恶寒发热。后必有渴水燥热之证。或逆厥而利。此热证传经之邪也。若始终皆热证。惟热而不恶
寒。故伤寒为病。初则头痛。必无发热恶寒渴水之症。一病便有逆厥泄利。或但恶寒而无发热。此寒症也。此识症之妙
也。如舌本者。乃心之窍于舌。心属火。主热。象离明。人得病。初在表。则舌自红而无白苔等色。表邪入于半表半里
之间。其舌色变为白苔而滑见矣。切不可不明表症。故邪传于里未罢。则舌必见黄苔。乃邪已入于胃。急宜下之。苔黄
自去而疾安矣。至此医之不根据次。误用汤丸。失于迟下。其苔必黑。变症蜂起。此为难治。若见舌苔如漆黑之光者。十
无一生。此心火自炎。与邪热二火相攻。极热则有兼化水象。故色从黑而应水化也。若乃脏腑皆受。邪毒日深。为症必
作热症。虽宜下之。乃去胸中之热。否则其热散入络脏之中。鲜有不死者。譬如火之自炎。初则红，过则薪为黑色炭矣。
此亢则害。承乃制。今以前十二舌明着。犹恐未尽诸症。复作二十四图。并方治列于左。则区区推源寻流。实可决生死
之妙也。
至正元年一阳月上浣之日
凡是伤寒热病在经络间传变的邪气，与一般的杂病不同。必须辨别其脉象、症状、舌苔以及表里、发汗和攻下的适宜时机，这样才不至于出现误诊误治。况且脉是血液汇聚之所，属于阴类。在疾病初起之时，正气与邪气相互搏结，如果真气尚未衰弱，脉象必然滑数而有力；若病程日久，热势炽盛而正气衰败，脉象必然微细而无力。这是脉象由数转甚的变化规律，此时只可滋养阴液以消退阳亢，这是掌握脉诊的关键所在。
有的患者在发病之初就出现恶寒发热，随后必然会出现口渴、燥热等症状；或者出现四肢逆冷并伴有下利，这是热证在经络间传变的邪气所致。如果始终都是热证，只有发热而没有恶寒，那么伤寒作为疾病，起初会有头痛，但绝不会有发热、恶寒、口渴饮水的症状（注：此处原文逻辑似有矛盾或特指某种寒证初期表现，依文意直译），一旦患病便出现四肢逆冷、泄泻下利，或者只是恶寒而没有发热，这属于寒证。这是掌握症状辨析的奥妙所在。
至于舌本，它是心的外窍。心属火，主司热，象征离卦的光明。人患病时，邪气初在体表，舌头自然发红而没有白苔等颜色；当表邪传入半表半里的位置时，舌色会发生变化，出现白苔且显得滑润。切不可不明确表证的情况。因此，当邪气传入体内尚未解除时，舌上必然出现黄苔，这说明邪气已经入胃，应当紧急使用攻下法。黄苔自然消退，疾病即可痊愈。如果医生不依据病情次第，错误地使用汤剂或丸药，延误了攻下的时机，舌苔必然变黑，各种变症蜂拥而起，这就难以治疗了。如果见到舌苔像漆黑光亮一样的，十个人中没有能活下来的，这是因为心火自燃，与邪热这两股火势相互攻击，极热之时会产生兼化水的现象，所以颜色呈现黑色以对应水的变化。如果脏腑都受到侵害，邪毒日益加深，病症必然表现为热证，虽然应该使用攻下法，但这只能去除胸中的热邪，否则热气会散入络脉和脏腑之中，很少有能存活的人。这就好比火焰自燃，起初是红色，过后木柴就变成了黑色的炭。这就是“亢则害，承乃制”的道理。现在将前面十二种舌象明确列出，又担心不能涵盖所有症状，于是再绘制二十四幅图，并将治疗方法列在左侧，这样推究本源、寻流溯源，确实具有决断生死的高妙之处。
至正元年（1341年）农历一月上旬的日子
The pathogenic factors of cold damage (Shanghan) and febrile diseases that transmit through the meridians differ from those of miscellaneous diseases. It is essential to differentiate their pulse, symptoms, tongue coating, as well as the indications for exterior-releasing (sweating) and purgative methods, so as to avoid diagnostic errors. The pulse is the mansion of blood and belongs to Yin. At the onset of illness, when healthy Qi contends with pathogens, if the True Qi has not yet declined, the pulse will necessarily be slippery, rapid, and forceful. If the disease persists for a long time with intense heat and declining Qi, the pulse will necessarily be faint, thin, and weak. This describes the progression from a frequent to an extreme pulse; at this stage, one should only nourish Yin to subdue Yang. This is the key to mastering pulse diagnosis.
Some patients present with aversion to cold and fever at the very beginning, followed inevitably by symptoms of thirst, dryness, and heat, or even cold extremities with diarrhea; these are pathogenic factors of heat syndromes transmitting through the meridians. If it remains a heat syndrome throughout, characterized solely by fever without aversion to cold, then regarding cold damage as a disease, it initially presents with headache but strictly lacks symptoms of fever, aversion to cold, and thirst for water. If the onset involves cold extremities and diarrhea, or merely aversion to cold without fever, this constitutes a cold syndrome. This is the subtlety of symptom differentiation.
As for the root of the tongue, it is the orifice of the Heart. The Heart belongs to Fire, governs heat, and corresponds to the brightness of the Li trigram. When a person falls ill and the pathogen is initially in the exterior, the tongue naturally turns red without white coating or other colors. When exterior pathogens enter the half-exterior, half-interior region, the tongue color changes, presenting a white coating that appears slippery. One must not fail to clarify exterior syndromes. Therefore, when pathogens have transmitted into the interior but have not yet resolved, the tongue will necessarily show a yellow coating, indicating that the pathogen has entered the Stomach; urgent purgation is required. Once the yellow coating disappears, the illness will resolve. However, if physicians do not follow the sequence of the disease and erroneously use decoctions or pills, delaying purgation, the coating will inevitably turn black, and various complicated symptoms will arise, making it difficult to treat. If the tongue coating appears like glossy pitch-black, ten out of ten cases will result in death. This occurs because Heart Fire flares up independently and attacks the pathogenic heat; extreme heat generates a transformation into Water characteristics, hence the color turns black to correspond to Water. If all Zang-Fu organs are affected and pathogenic toxins deepen daily, the symptoms will manifest as heat syndromes. Although purgation is indicated, it primarily clears heat from the chest; otherwise, the heat will scatter into the collaterals and Zang-Fu organs, and survival is unlikely. This is analogous to fire burning: initially red, but eventually the fuel turns into black charcoal. This illustrates the principle that "excess leads to harm, and control follows." Now, having clearly presented the twelve tongue images above, and fearing they may not cover all symptoms, I have additionally created twenty-four illustrations and listed the corresponding treatments below. Thus, tracing the source and following the flow truly offers the profound ability to determine life and death.
On the morning days of the first lunar month of the first year of Zhizheng [1341 AD]