丹溪曰仲景论伤寒矣而未及乎中寒先哲治胃大寒而昏用附子理中而安其议药则得之矣曰
伤曰
中未闻有议其异同之者因思伤寒有即病有不即病必大发热邪循经而入以渐而深中寒则仓卒感
受其病即发而暴伤寒之人因其旧有郁热风寒外来肌腠自密郁发为热其初也用麻黄桂枝辈发表
而安以病体不甚虚也中寒之人乘其肤腠疏豁一身受邪难分经络无热可发温补自解此胃气之大
虚也伤寒热虽甚不死中寒若不急治去生甚远其虚实盖可见矣
谨按仲景论伤寒至三阴病例可汗外感也韩祗和例温中即中寒也张洁古三阴可下王海藏例
可补
皆言内伤也但韩氏不直指中寒而就于阴证立便例例可温中之法与仲景三阴病论证不同乃别立
方意指中寒而未甚莹故丹溪先生重明此意然皆宜详玩临证合宜处治也
内经曰阳虚则外寒者阳受气于上焦以温皮肤分肉之间令寒气在外则上焦不通上焦不通则
寒气
独留于外故寒栗 阴盛则内寒者因厥气上逆寒气积于胸中而不泻不泻则温气去寒独留则血凝
泣凝则脉不通其脉盛大以涩故中寒
按此言阴阳虚盛为寒本七情所动之致义见调经
东垣曰夜则恶寒昼则安静是阴血自旺于阴分也
夜则恶寒昼则恶寒是重阴无阳也当亟泻其阴峻补其阳 夜则安静昼则恶寒是阴气上溢于
阳中也
按此亦阴盛所致之本病非感寒外因也伤寒外因三阳恶寒皆表邪未解太阴手足自温故不恶
寒少阴厥阴手足厥逆而恶寒者阴盛然也与此稍异
朱丹溪说：张仲景论述了伤寒，却没有涉及中寒。先贤在治疗胃中大寒导致昏迷时，使用附子理中汤而使其安定，他们在议药方面是得当的。但是只提到“伤”，没有提到“中”，未曾听说有人讨论过它们的异同。我想到伤寒有即发和不即发的区别，必定是大发热，邪气循经而入，逐渐深入；中寒则是仓促感受，病发急骤且猛烈。患伤寒的人，因为体内原有郁热，风寒从外来侵袭，肌腠致密，郁结化热，初起时用麻黄、桂枝等药物发表，这是适宜的，因为患病体质不是很虚弱。患中寒的人，趁着肌肤腠理疏豁，全身受邪，难以分辨经络，没有热可发，需要用温补来解除，这是胃气的大虚。伤寒虽然发热严重但不会致死，中寒如果不紧急治疗，离死亡就很远了，虚实的情况大概就可以看出来了。
谨按：张仲景论述伤寒，到了三阴病，病例可以汗解，属于外感。韩祗和列举温中的方法，就是针对中寒。张洁古认为三阴病可以用下法，王海藏列举可以补的方法，都是指内伤。但是韩氏不直接指出中寒，而是就阴证立例，列举可温中的方法，与张仲景三阴病的论证不同，乃是另外设立方剂，意指中寒但不够明确透彻，所以朱丹溪先生重新阐明这个意思。然而这些都应当详细研读，临证时根据适宜的情况处理。
《内经》说：“阳虚则外寒”，是因为阳气在上焦受气，以温煦皮肤和分肉之间。如果寒气在外，则上焦不通，上焦不通则寒气独留于外，所以出现寒战。阴盛则内寒，是因为厥气上逆，寒气积聚在胸中而不能排泄，不能排泄则温气离去，寒气独留，血液凝涩，凝涩则脉道不通，其脉盛大而涩，所以发生中寒。按照此言，阴阳虚盛导致的寒冷，本是由于七情所动所致，这一义理见于《调经》篇。
李东垣说：夜间恶寒，白天安静，这是阴血在阴分旺盛的表现。夜间恶寒，白天也恶寒，这是重阴无阳，应当紧急泻其阴，峻补其阳。夜间安静，白天恶寒，这是阴气上溢于阳中。
按：这也是阴盛所致，根本病症并非感受寒邪的外因。伤寒外因导致的三阳恶寒，都是表邪未解；太阴病手足自温，所以不恶寒；少阴、厥阴病手足厥逆而恶寒，是阴盛所致，与此稍有不同。
Zhu Danxi stated: Zhang Zhongjing discussed Shanghan (Cold Damage) but did not cover Zhonghan (Cold Stroke). Ancient sages, when treating severe cold in the stomach leading to coma, used Fuzi Lizhong Tang (Aconite and Poria Decoction for Regulating the Middle) to bring peace; their discussion on medication was appropriate. However, they only mentioned "Shang" (Injury) and not "Zhong" (Stroke), and it is unheard of that anyone discussed the similarities and differences between them. I reflect that Shanghan has cases that manifest immediately and those that do not; it necessarily involves high fever, with pathogenic factors entering via the meridians and gradually deepening. Zhonghan, however, results from sudden exposure, causing immediate and violent onset. Patients with Shanghan have pre-existing stagnant heat within; when wind-cold invades externally, the muscle interstices become dense, leading to stagnation and transformation into heat. In the initial stage, using Ma Huang (Ephedrae Herba) and Gui Zhi (Cinnamon Twig) to release the exterior is appropriate because the patient's constitution is not significantly deficient. Patients with Zhonghan, taking advantage of open and loose skin pores, suffer from pathogenic invasion throughout the body, making it difficult to distinguish meridians; there is no heat to release, so warming and tonification are required for resolution, indicating a severe deficiency of Stomach Qi. Although Shanghan involves severe fever, it is not fatal; if Zhonghan is not treated urgently, death is imminent. Thus, the distinction between deficiency and excess is evident.
Note: Zhang Zhongjing’s discussion of Shanghan extends to the Three Yin syndromes, where cases can be treated with sweating methods, belonging to external contraction. Han Zhihe listed warming methods, which target Zhonghan. Zhang Jiegu argued that Three Yin syndromes could be treated with purgatives, and Wang Haizang listed methods suitable for tonification; all refer to internal injury. However, Han Shi did not directly point out Zhonghan but established examples based on Yin syndromes, listing methods for warming the middle, differing from Zhang Zhongjing’s argumentation for Three Yin diseases. He established separate formulas, implying Zhonghan but lacking clarity. Therefore, Mr. Zhu Danxi re-emphasized this meaning. Nevertheless, these texts should be studied in detail, and clinical treatment should be adapted appropriately.
The Neijing states: "Yang deficiency leads to external cold." This is because Yang Qi receives its energy from the Upper Jiao to warm the skin and muscle spaces. If cold pathogen remains outside, the Upper Jiao becomes obstructed. Obstruction of the Upper Jiao causes cold pathogen to remain exclusively outside, resulting in chills. "Yin excess leads to internal cold." This occurs due to rebellious Qi moving upward, causing cold pathogen to accumulate in the chest without being discharged. Without discharge, warming Qi departs, leaving cold pathogen alone. Blood coagulates and stagnates; stagnation blocks the vessels. The pulse is large and forceful yet choppy, thus causing internal cold. According to this, cold caused by Yin-Yang deficiency or excess originates from emotional disturbances, as explained in the Tiaojing chapter.
Li Dongyuan stated: Chills at night and tranquility during the day indicate that Yin Blood is flourishing in the Yin aspect. Chills at both night and day indicate excessive Yin with absent Yang; one should urgently drain the Yin and vigorously tonify the Yang. Tranquility at night and chills during the day indicate that Yin Qi overflows into the Yang aspect.
Note: This is also caused by Yin excess; the root disease is not an external factor of contracting cold. In Shanghan caused by external factors, chills in the Three Yang syndromes indicate unresolved exterior pathogens. In Taiyin syndrome, the hands and feet are warm, so there are no chills. In Shaoyin and Jueyin syndromes, the hands and feet are cold and there are chills, which is due to Yin excess. This differs slightly from the aforementioned conditions.