大伤寒者。冬月天气严寒。水冰地冻。而成杀厉之气。体弱之人。触犯之者。中则即病
。名曰正伤寒。不即病者。乃寒邪藏于肌肤之间。伏于荣卫之内。至春因温暖之气而发者
名曰温病。至夏因暑热而发者名曰热病。虽曰伤寒。实为热病。凡治伤寒。必先辨明六经。
而后
。而诊之则尺寸俱浮。浮紧有力为伤寒。浮缓无力为伤风。而太阳经症可辨矣。太阳病已。
以次而传经。必传于胃。发于一三日之间。便觉目疼鼻干不得眠。日晡潮热。不恶寒而反恶
热者。乃太阳阳明胃经受病也。而诊之则尺寸俱长。长而微洪者脏病。长而沉数者腑病。而
阳明症可辨矣。阳明病已。以次而传经必传于胆。发于三四日之间。便觉胸胁痛而耳聋。寒
热呕而口为之苦。乃足少阳胆经受病也。而胗之则尺寸俱弦。弦而滑数者病发厥。弦而和者
病欲散。而少阳经病可辨矣。少阳病已。以次而传经必传于脾。发四五日间。便觉腹满或痛
。而咽喉干燥。大便不通。小便如常。或自利。手足温而渴者。为传经腑热。起无头疼发
热。但恶寒自利不渴。手足冷者。为直中阴经。乃是太阴脾经受病也。而胗之则尺寸俱沉。
沉实有力为里实热。沉迟无力为里虚寒。而太阴经症可辨矣。太阴病已。以次而传经必传于
肾。发于五六日间。便觉口燥舌干而渴。手足乍温乍冷。便秘谵语者为热。或泄泻清谷不渴
。手指甲而青者为寒。乃足少阴肾经受病也。而胗之则尺寸俱沉。沉实有力知其热。沉迟
无力别其寒。而少阴经症可辨矣。少阴病已。以次而传经必传于肝。发于六七日间。便觉烦
懑而囊缩。谵语而渴者为热。口吐涎沫小腹痛不渴。身冷如冰者为寒。乃足厥阴肝经受病也
。而胗之则尺寸俱沉。沉实有力是其热。沉迟无力定知寒浮缓者病自愈而厥阴经症可辨矣。
又有两感伤寒者何也。假如一日太阳与少阴俱病。头疼为太阳邪盛于表。口干烦满为少阴邪
盛于里。二日阳明与太阴俱病。身热谵语为阳明邪盛于表。不欲食腹满为太阴邪盛于里。三
日少阳与厥阴俱病。耳聋为少阳邪盛于表。囊缩而厥。为厥阴邪盛于里。若水浆不入。又
不知人者。六日死。以其一脏一腑同受其邪。此两感之所以不救也。然其间亦有轻重之不同
。表重于里者。宜先救其表。而后及于里。里重于表者。宜先救其里。而后及于表。此又
求于一生于万死之中。不得已而施治也。其不两感于寒。更不传经者。至七八日间。其本经
之邪渐遏。至十二日则精神清爽而自愈。然伤寒传经种种不同。未可执为一定之序。有始于
太阳。以次而传入阴经。而不传少阴者。或太阳不传阳明少阳。而即传少阴者。或不由阳经
而直入阴经者。或始终即在一经。而不传者。或二阳三阳同受而为合病者。或太阳阳明先后
受而为并病者。种种不一详。审而治可也。又有中寒一症。或卒。中天地之寒气。或口得寒
物直中阴经。六脉沉弱无力。身倦手足厥冷。口噤不语。非若伤寒之邪。循经渐深也。然真
正伤寒。与感冒伤寒。及似伤寒。而非伤寒者。何以辨之。盖寒者。冬月严凝。肃杀之气也
。自霜降以后。春分以前。皆属冬。此时感冒而即发者。乃为真正伤寒也。若冬伤于寒不即
病。至春分后而发者。名曰温病。其症发热咳嗽。身痛口渴不恶寒。其脉弦数不紧。右手反
盛于左手。盖怫然在内故也。冬伤于寒春亦不病。到夏至后而发者。名曰热病其脉洪数。其
症热渴。比春更甚。温热二症俱不恶寒而渴。不恶寒则病非外来。渴则热自内达于表间。有
恶寒者。乃冒非时暴寒。非若冬月之甚也。其有不因冬伤于寒。而春自伤于风。夏自伤于暑
者。则自有伤风伤暑之别。而又不可以温热并论矣。或有感于天行时气。而病相同者。谓之
温疫。其症头疼身痛。发寒发热。一家一方长幼传染者是也。或足膝等处忽然红肿。或软弱
发热头疼。谓之香港脚伤寒。或心腹饱闷。呕逆头疼。发热恶寒。右手关脉紧盛。左手三奇和
平。而身不痛者。是伤食也若头痛而身亦痛左右手俱紧盛。谓之夹食伤寒。左手脉来紧盛。
右手洪滑。或寸脉沉伏。身热恶寒。隐隐头痛。喘咳烦闷。胸胁体痛。是夹痰伤寒。头痛发
热恶寒。但右手脉来空虚。左手脉来紧盛。是劳力伤寒。左手脉来紧涩。右手脉沉芤。心胸
胁下小腹有痛处。汗至胫而回。是蓄血伤寒。太阳症则如狂。阳明症则善忘。少阳症则寒热
似疟。此皆类伤寒。而非伤寒也。其余伤寒中杂症颇多。不能枚举。皆诸病门中所有者。但
杂症一兼伤寒。即所谓伤寒杂症。医者以意求之。则不言而自喻矣。
Da Shanghan (Major Cold Damage) refers to the condition where, during the severe cold of winter, water freezes and the ground cracks, forming a lethal qi (vital energy/pathogenic factor). Individuals with weak constitutions who are exposed to this pathogen will fall ill immediately upon infection, which is termed Zheng Shanghan (True Cold Damage). If illness does not occur immediately, the cold pathogen hides between the skin and muscles, lying dormant within Ying (Nutritive Qi) and Wei (Defensive Qi). When spring's warm air arrives, it may manifest as Wenbing (Warm Disease); if it manifests in summer due to summer-heat, it is called Rebing (Heat Disease). Although collectively referred to as Shanghan, they are essentially Heat Diseases. In treating Shanghan, one must first differentiate the Six Channels (Taiyang, Yangming, Shaoyang, Taiyin, Shaoyin, Jueyin), and only then proceed with diagnosis.
Upon pulse diagnosis, if the Cun, Guan, and Chi positions at both wrists are floating, and the pulse is floating, tight, and forceful, it indicates Shanghan; if it is floating, slow, and weak, it indicates Shangfeng (Wind Strike). Thus, the syndromes of the Taiyang Channel can be identified. After the Taiyang disease resolves, the pathogen transmits sequentially, inevitably entering the Stomach Channel (Yangming Channel). This typically occurs within one to three days, presenting with eye pain, nasal dryness, insomnia, tidal fever in the late afternoon (Ribu), aversion to heat rather than cold. This indicates pathology in the Taiyang and Yangming Stomach Channels. Pulse diagnosis reveals long pulses at all positions; a long and slightly surging pulse indicates Zang (Organ) disease, while a long and deep-rapid pulse indicates Fu (Hollow Organ) disease. Thus, Yangming syndromes can be identified.
After Yangming disease resolves, transmission proceeds to the Gallbladder Channel (Shaoyang Channel). Occurring within three to four days, symptoms include chest and hypochondriac pain, deafness, alternating chills and fever, vomiting, and bitter taste in the mouth. This indicates pathology in the Foot-Shaoyang Gallbladder Channel. Pulse diagnosis shows wiry pulses at all positions; a wiry, slippery, and rapid pulse indicates the onset of Jue (reversal/cold limbs), while a wiry and harmonious pulse indicates the disease is resolving. Thus, Shaoyang syndromes can be identified.
After Shaoyang disease resolves, transmission proceeds to the Spleen Channel (Taiyin Channel). Occurring around four to five days, symptoms include abdominal fullness or pain, dry throat, constipation, normal urination, or spontaneous diarrhea, warm hands and feet, and thirst. This indicates transmitted Fu-heat. If there is no headache or fever initially, but only aversion to cold, spontaneous diarrhea without thirst, and cold hands and feet, it is "Direct Invasion of Yin Channels," indicating pathology in the Taiyin Spleen Channel. Pulse diagnosis shows deep pulses at all positions; a deep, solid, and forceful pulse indicates interior excess-heat, while a deep, slow, and weak pulse indicates interior deficiency-cold. Thus, Taiyin syndromes can be identified.
After Taiyin disease resolves, transmission proceeds to the Kidney Channel (Shaoyin Channel). Occurring around five to six days, symptoms include dry mouth and tongue with thirst, and hands and feet that alternate between warm and cold. Constipation with delirium indicates heat; diarrhea with undigested food, no thirst, and blueish fingernails indicate cold. This indicates pathology in the Foot-Shaoyin Kidney Channel. Pulse diagnosis shows deep pulses at all positions; deep, solid, and forceful indicates heat, while deep, slow, and weak indicates cold. Thus, Shaoyin syndromes can be identified.
After Shaoyin disease resolves, transmission proceeds to the Liver Channel (Jueyin Channel). Occurring around six to seven days, symptoms include irritability and retraction of the testicles. Delirium with thirst indicates heat; salivation, lower abdominal pain without thirst, and body cold as ice indicate cold. This indicates pathology in the Foot-Jueyin Liver Channel. Pulse diagnosis shows deep pulses at all positions; deep, solid, and forceful indicates heat, deep, slow, and weak indicates cold, and floating-slow indicates spontaneous recovery. Thus, Jueyin syndromes can be identified.
What is Lianggan Shanghan (Double-Infection Cold Damage)? For example, on the first day, both Taiyang and Shaoyin channels are affected: headache indicates excessive Taiyang pathogen on the exterior; dry mouth and irritability/fullness indicate excessive Shaoyin pathogen on the interior. On the second day, both Yangming and Taiyin are affected: body heat and delirium indicate excessive Yangming pathogen on the exterior; anorexia and abdominal fullness indicate excessive Taiyin pathogen on the interior. On the third day, both Shaoyang and Jueyin are affected: deafness indicates excessive Shaoyang pathogen on the exterior; testicular retraction and cold limbs indicate excessive Jueyin pathogen on the interior. If the patient cannot take fluids and loses consciousness, death occurs after six days because one Zang and one Fu organ are simultaneously infected by the pathogen; this is why Lianggan is incurable. However, severity varies. If exterior syndrome is heavier than interior, treat the exterior first, then the interior. If interior is heavier, treat the interior first, then the exterior. This is a desperate measure to save life from death.
For those not suffering from double-infection and without transmission, by the seventh or eighth day, the pathogen in the primary channel is gradually suppressed, and by the twelfth day, mental clarity returns, and the disease heals spontaneously. However, transmission patterns vary and should not be rigidly fixed. Some start in Taiyang and transmit to Yin channels without involving Shaoyin; some skip Yangming and Shaoyang to involve Shaoyin directly; some bypass Yang channels entirely to enter Yin channels; some remain confined to one channel; some involve simultaneous infection of two or three Yang channels (Hebing/Combined Disease); some involve sequential infection of Taiyang and Yangming (Bingbing/Concurrent Disease). These cases require careful differentiation and treatment.
There is also Zhonghan (Cold Strike), caused suddenly by heaven-earth cold qi or ingestion of cold substances directly invading Yin channels. The six pulses are deep, weak, and powerless; the body is fatigued, hands and feet are cold, jaw is locked, and speech is impaired. This differs from Shanghan, where the pathogen penetrates gradually along the channels.
How to distinguish True Shanghan from Ganmao Shanghan (Common Cold-type Cold Damage) and Lei Shanghan (Shanghan-like conditions)? Han (Cold) is the severe, killing qi of winter. From Shuangjiang (Frost Descent) to Chunfen (Spring Equinox), any immediate illness after exposure is True Shanghan. If cold is contracted in winter but manifests after Chunfen, it is Wenbing (Warm Disease), with symptoms of fever, cough, body ache, thirst, no aversion to cold, wiry-rapid non-tight pulse, and right-hand pulse stronger than left due to internal constraint. If contracted in winter but manifests after Xiazhi (Summer Solstice), it is Rebing (Heat Disease), with surging-rapid pulse and more severe heat/thirst than in spring. Both Warm and Heat diseases feature thirst without aversion to cold, indicating internal heat reaching the surface. Aversion to cold suggests exposure to sudden abnormal cold, less severe than winter cold.
If illness arises from spring wind or summer summer-heat independently, it is distinct from Warm/Heat diseases. If contracted from epidemic qi with similar symptoms, it is Wenyi (Warm Epidemic), characterized by headache, body ache, chills/fever, and family contagion. Sudden redness/swelling of legs/knees or weakness/fever/headache is Hongxiangjiao Shanghan (Hongxiangjiao Cold Damage, i.e., Beriberi). Fullness in heart/abdomen, vomiting, headache, fever, aversion to cold, tight-full Guan pulse on right,平和 Pinghe (harmonious) pulses on left, and no body pain indicate Shangshi (Food Injury). Headache with body pain and tight pulses on both hands is Jiashi Shanghan (Shanghan with Food Retention). Tight left pulse, surging-slippery right pulse, or deep-fu Cun pulse, with fever, aversion to cold, vague headache, wheezing/cough, irritability, and chest/hypochondriac/body pain indicates Jiatan Shanghan (Shanghan with Phlegm). Headache, fever, aversion to cold, empty right pulse, and tight left pulse indicates Laoli Shanghan (Shanghan from Overwork). Tight-severe left pulse, deep-kou right pulse, pain in chest/abdomen, and sweat returning below knees indicates Xuxue Shanghan (Shanghan with Blood Stasis). Taiyang syndrome presents like mania; Yangming syndrome presents with forgetfulness; Shaoyang syndrome presents with chills/fever resembling malaria. These are Lei Shanghan (Shanghan-like), not true Shanghan.
Other miscellaneous disorders within Shanghan are numerous and listed in other sections. When miscellaneous disorders coexist with Shanghan, they are termed Shanghan Zazheng (Miscellaneous Disorders with Shanghan). Physicians should deduce the nature through clinical reasoning.