内经素问有热论篇首言热病者。皆伤寒之类。又有刺热篇。言五脏热病。此系杂证。灵枢又有热病篇。其中言
热病三日。或七八日。或已得汗或未曾汗。或口中干。胸胁满或头痛耳聋。皆伤寒之类也。黄帝岐伯论伤寒。惟以
热为主。至仲景论伤寒。则寒热并举。何也。夫人身之中。有阴有阳。有寒有热。有虚有实。此其常也。有阳极似
阴。有阴极似阳。有热极而寒。有寒极而热。有大实若虚。有大虚若实。此其变也。余曾辩注伤寒论一十四卷。若
阳邪热实之证。已畅发而无余蕴矣。兹更集中寒论三卷。于仲景书中。摘其所谓真阴虚寒之证。逐条辩解。每方注
明只因仲景当日。不分阴阳虚实寒热而总谓之伤寒。余因不得已而述是书也。或云。内经中无寒论。及寒病篇。故
仲景当日。以寒病杂之伤寒论中。不敢创为一论。更分一门。今吾子知尊仲景矣。又别立中寒方论。得母僭欤。余
答云。前圣之制作。专待后人之阐扬。据仲景自论云。撰用素问九卷。八十一难。阴阳大论。胎胪药录。并平脉辩
证。为伤寒杂病论。合十六卷。虽曰伤寒。而痉湿 霍乱等杂病。俱在其中。所未分者。岂特一中寒邪。丹溪有云。
仲景辩伤寒矣。而未及乎中寒。非曰无中寒也。言未及辩别也。中寒未及辩别。以致俗医。有以伤寒皆变为热。并
无所谓真阴证者。有以阳证入阴。即阴虚为阴证者。有以热病服凉药太过。即变为阴证者。有以头不痛之杂病。为
阴证者。有以曾犯房室为阴证者。殊不知中寒之人。三焦火衰。元气大虚。又受外来风寒之邪。其为中也。或中于
阳。或中于阴。皆寒病也。其中于阳而为寒病者。以始入太阳。太阳与少阴为表里。少阴者。肾也。邪在太阳。膀
胱为寒水之经。肾家无火。不能御寒。为真阴证。犹之阳邪传入阴经。亦热病也。又有胸以前受寒气。及冷物入胃
。胃为阳明之腑。与太阴脾脏相根据附。胃中无火。则脾气大寒。亦为真阴证。犹之伤寒挟食。邪已入腑。为实热病
也。此其义仲景实未尝及。然于霍乱一病。有寒多不饮水者。用理中汤丸加附子。斯言已得之矣。又有寒中厥阴之
经肝脏虚。寒气上攻而头痛者。亦为真阴证也。又有小儿未犯房室。而中寒。如慢惊之类。亦为真阴证也。此但举
其大略。而后学可以起悟。愚以中寒之证。仲景立法。中经者。皆主温散。问有中脏者。亦主热发。所以诸汤中附
子。生用者极多。而炮者甚少。偶有同人参白术芍药当归共剂者。或从气虚。或从血少也。其有或吐或利。四肢厥
逆。胃气大虚。无热可发者。法当温补。更有里寒虽极。肠胃中实者。又宜温中消导。若例用补药。岂不大误。此
皆仲景所未言及者。愚以后贤方论补之而已。
The *Su Wen* (Basic Questions) chapter of the *Nei Jing* (Inner Canon) contains a section titled "Re Lun" (Discourse on Heat Diseases), which states at the beginning: "All heat diseases belong to the category of Shang Han (Cold Damage)." There is also the "Ci Re Pian" (Chapter on Acupuncture for Heat Diseases), discussing heat diseases of the five Zang organs, which fall under miscellaneous diseases. The *Ling Shu* (Spiritual Pivot) also has a "Re Bing Pian" (Chapter on Heat Diseases), stating: "In heat disease lasting three days, or seven to eight days, whether sweating has occurred or not, whether the mouth is dry, chest and hypochondrium are full, or there is headache and deafness, all these belong to the category of Shang Han." In the dialogue between Huang Di (Yellow Emperor) and Qi Bo regarding Shang Han, only heat was emphasized. However, when Zhang Zhongjing discussed Shang Han, he presented both cold and heat. Why is this?
Within the human body, there is Yin and Yang, cold and heat, deficiency and excess; this is the normal state (Chang). However, there are also abnormal states (Bian): extreme Yang resembling Yin, extreme Yin resembling Yang, extreme heat generating cold, extreme cold generating heat, great excess appearing as deficiency, and great deficiency appearing as excess. I previously annotated fourteen volumes of the *Shang Han Lun* (Treatise on Cold Damage), thoroughly expounding upon syndromes of Yang pathogenic factors and heat excess without omission. Now, I have concentrated my efforts on compiling three volumes of the *Zhong Han Lun* (Treatise on Intermediate Cold), extracting from Zhongjing’s works those syndromes described as "true Yin deficiency-cold," explaining them item by item. For each formula, I note the reason: simply because Zhongjing, at that time, did not distinguish between Yin/Yang, deficiency/excess, cold/heat, but collectively termed them "Shang Han." Thus, I felt compelled to write this book.
Some have said: "The *Nei Jing* lacks a 'Han Lun' (Discourse on Cold) or 'Han Bing Pian' (Chapter on Cold Diseases). Therefore, Zhongjing mixed cold diseases into his *Shang Han Lun*, daring not create a separate discourse or classify them into a distinct category. Now that you revere Zhongjing, yet establish a separate 'Zhong Han Fang Lun' (Discourse on Formulas for Intermediate Cold), is this not an overstep?"
I reply: "The creations of former sages await later generations to elucidate and promote them. According to Zhongjing’s own statement: 'I compiled the *Su Wen* nine volumes, the *Nan Jing* (Classic of Difficult Issues), the *Yin Yang Da Lun* (Great Discourse on Yin and Yang), the *Tai Lu Yao Lu* (Record of Fetal Protection and Materia Medica), along with pulse differentiation and syndrome discrimination, into the *Shang Han Za Bing Lun* (Treatise on Cold Damage and Miscellaneous Diseases), totaling sixteen volumes.' Although named Shang Han, it includes miscellaneous diseases such as Jing (Stiffness/Spasm), Shi (Dampness), and Huo Luan (Cholera-like disorder). What was not separately classified was not merely the pathogen of Intermediate Cold. Zhu Danxi stated: 'Zhongjing differentiated Shang Han but did not address Zhong Han.' This does not mean Zhong Han does not exist, but rather that it was not sufficiently differentiated. Because Zhong Han was not differentiated, common physicians have erred in various ways: some believe all Shang Han transforms into heat, denying the existence of true Yin syndromes; some consider any Yang syndrome entering the Yin meridians as a Yin syndrome caused by Yin deficiency; some believe excessive use of cooling medicines for heat diseases transforms them into Yin syndromes; some mistake miscellaneous diseases without headache as Yin syndromes; some attribute sexual indiscretion as the cause of Yin syndromes. They fail to realize that patients suffering from Zhong Han have declining Fire of the San Jiao (Triple Burner) and significant depletion of Yuan Qi (Original Qi), compounded by external invasion of Wind-Cold pathogens. The pathogen may strike the Yang meridians or the Yin meridians; both constitute Cold diseases.
When striking the Yang meridians resulting in a Cold disease, it begins in the Taiyang (Greater Yang) meridian. Taiyang and Shaoyin (Lesser Yin) are exterior-interior pairs. Shaoyin corresponds to the Kidney. When the pathogen is in Taiyang, the Bladder is the meridian of Cold Water. If the Kidney lacks Fire, it cannot resist the Cold, resulting in a True Yin syndrome. This is analogous to Yang pathogens transmitting to Yin meridians, which still constitutes a Heat disease. Furthermore, if Cold air affects the upper chest, or cold substances enter the Stomach, since the Stomach is the Fu organ of Yangming (Yang Brightness) and is closely associated with the Taiyin (Greater Yin) Spleen, a lack of Fire in the Stomach leads to severe Cold in the Spleen Qi, also constituting a True Yin syndrome. This parallels Shang Han complicated by food stagnation, where the pathogen has entered the Fu organs, becoming a Excess-Heat disease. These principles were indeed not explicitly addressed by Zhongjing. However, in the case of Huo Luan, he mentioned using Lizhong Tang Wan (Regulate the Middle Decoction/Pill) with added Fuzi (Prepared Aconite Root) for cases with much cold and no desire to drink water, which captures the essence. Additionally, when Cold strikes the Jueyin (Terminal Yin) meridian, causing Liver deficiency and Cold Qi attacking upward leading to headache, this is also a True Yin syndrome. In children who have not engaged in sexual activity but suffer from Zhong Han, such as in Slow Convulsion (Man Jing), this is also a True Yin syndrome. I list only the general outline here, so that future students may gain insight.
Regarding the treatment principles for Zhong Han established by Zhongjing: for pathogens affecting the meridians, warming and dispersing methods are primarily used. For pathogens affecting the Zang organs, hot/warming herbs are used to disperse. Consequently, raw Fuzi is used extensively in various decoctions, while processed Fuzi is rare. Occasionally, herbs such as Renshen (Ginseng Radix), Baizhu (Atractylodis Macrocephalae Rhizoma), Shaoyao (Paeoniae Radix), and Danggui (Angelicae Sinensis Radix) are combined, addressing either Qi deficiency or Blood insufficiency. In cases involving vomiting or diarrhea, cold limbs (Jue Ni), severe Stomach Qi deficiency, and absence of fever to be dispersed, the method should be Warming and Tonifying. In cases where interior Cold is extreme but there is Excess in the intestines and stomach, one should employ Warming the Middle combined with Digestion-promoting methods. To indiscriminately use tonifying herbs would be a major error. These points were not mentioned by Zhongjing; as a later scholar, I supplement them with formulas and discussions.