【纲】仲景曰。伤寒五六日。头痛。汗出。微恶寒。手足冷。心下满。口不欲食。大便硬。脉沉
细者。此为阳微结。必有表复有里也。脉沉。亦在里也。汗出为阳微结。假令纯阴结。不得复有外
症。悉入在里矣。此为半在表半在里也。脉虽沉细。不得为少阴病。所以然者。阴不得有汗。今
头汗出。故知非少阴也。可与小柴胡汤。设不了了者。得屎而解。
【目】成无己曰。邪之客于表者为寒。邪与阳相争则为寒矣。邪之入于里者为热。邪与阴相争
则为热矣。邪在半表
里。外与阳争而为寒。内与阴争而为热。是以往来寒热。邪居表多则多寒。邪居里多则多热。邪
半在表半在里。则寒热亦半矣。邪在表者。必渍形以为汗。邪在里者。必荡涤以取利。其余不外不内。半表半
里。又非发汗所宜。又非吐下所对。是当和解则可矣。小柴胡是也。
戴原礼曰。论中有曰太阳经病者。太阴经病者。有曰伤寒者。中风者。有但曰厥者。下利者。
有但曰病者。有但曰某经者。盖以邪中其经。故以经名之。非特谓伤寒之候。谓兼有杂病也。凡云
伤寒而不云经者。故非杂病也。谓六经俱有之症。难以一经拘之。中风亦然。凡云下利及厥。与夫称
病患等名症者。谓六经、伤寒、中风、杂病等候。俱有是症也。善治病者。须要详辨。太阳传经之
邪。各经直中之邪。曾无汗吐下之症。火逆、水喷之症。结胸、发黄、血滞、痞利、厥逆之症。如
中风、伤寒、杂病之候。一切之疾。不拘六经。但分表里。盖六经俱有表里二症。但有表症。即发
汗。但有里症。即攻下。或表里症俱见。则宜以攻里发汗之药。分表里病症多少用之。病在半表里。
和解之。此传经之治也。杂病寒症在表者。辛温汗之。寒中里者。大热救之。亦在明其表里而已。
李 曰。凡病或渴或不渴。或胸中烦不烦。或呕不呕。或腹胁痛不痛。或咳。或心下悸。或小
便不利。少阳所主也。或烦或呕者。邪在表。方传里也。若见耳聋胁痛寒热。呕而口苦。胸胁紧满。
脉弦数。即是半表半里。脉大胸满。多痰。或挟宿食。可吐。百问云。气浮上部。填塞心胸。头
痛多涎。此吐症也。经云。其高者因而越之。脉虽大。无甚痰者。不可吐。只宜和解。
[General Principle] Zhang Zhongjing stated: In the course of a cold damage disease, after five or six days, if headache, sweating, slight aversion to cold, coldness of the hands and feet, fullness in the epigastrium, anorexia, hard stools, and a deep, fine pulse are present, this is termed "Yang Wei Jie" (mild Yang constraint). There must be both exterior and interior manifestations. A deep pulse indicates the pathology is within the interior. Sweating occurs due to mild Yang constraint. If it were a pure Yin constraint, there would be no exterior symptoms remaining; all symptoms would have entered the interior. This represents a condition where the pathogen is half in the exterior and half in the interior. Although the pulse is deep and fine, it cannot be diagnosed as Shao Yin disease. The reason for this judgment is that Yin conditions typically do not present with sweating. Since there is sweating on the head, we know this is not Shao Yin disease. Xiao Chai Hu Tang (Minor Bupleurum Decoction) may be administered. If the patient remains uncomfortable after taking the medicine, recovery will occur upon defecation.
[Detailed Commentary] Cheng Wuji stated: When pathogens lodge in the exterior, they are considered Cold; when pathogens contend with Yang Qi, chills manifest. When pathogens enter the interior, they are considered Heat; when pathogens contend with Yin, fever manifests. When pathogens reside in the half-exterior/half-interior region, contending outwardly with Yang causes chills, while contending inwardly with Yin causes fever. Hence, alternating chills and fever occur. If pathogens are predominantly in the exterior, chills are more prominent; if predominantly in the interior, fever is more prominent. When pathogens are half in the exterior and half in the interior, the chills and fever are also mixed. For pathogens in the exterior, one must soak the body to induce sweating; for pathogens in the interior, one must purge the bowels to promote evacuation. For those neither purely exterior nor purely interior, but in the half-exterior/half-interior state, neither diaphoresis nor emesis/purgation is appropriate; instead, harmonization should be employed, such as with Xiao Chai Hu Tang.
Dai Yuanli stated: In medical texts, some refer to Tai Yang meridian diseases, others to Tai Yin meridian diseases; some are called Shang Han (Cold Damage), others Feng Zhong (Wind Strike); some are merely referred to as Jue (cold extremities/shock), others as Li Xie (diarrhea); some are simply called Bing (disease), others by specific meridians. This is because pathogens strike specific meridians, so they are named after those meridians, indicating not only Shang Han patterns but also concurrent miscellaneous diseases. Whenever Shang Han is mentioned without specifying a meridian, it implies these are not mere miscellaneous diseases but symptoms common to all Six Meridians, which cannot be confined to a single meridian; the same applies to Feng Zhong. Whenever Li Xie (diarrhea) and Jue (shock/cold extremities) are mentioned, along with general terms like "patient," it refers to symptoms that can appear across Six Meridian diseases, Shang Han, Feng Zhong, and miscellaneous diseases. A skilled physician must distinguish carefully. Whether it is pathogenic factors transmitted from Tai Yang, or direct invasion into various meridians, whether cases lacking prior sweating, vomiting, or purging treatments, or those involving fire-induced complications, water-spitting complications, Jie Xiong (chest binding), jaundice, blood stasis, Pi Li (fullness and diarrhea), or Jue Ni (rebellious cold), as well as patterns of Feng Zhong, Shang Han, and miscellaneous diseases—all ailments should not be rigidly bound by the Six Meridians but differentiated by Exterior and Interior. Generally, each of the Six Meridians has both Exterior and Interior presentations. If only Exterior symptoms exist, employ diaphoresis; if only Interior symptoms exist, employ purgation. If both Exterior and Interior symptoms are present, use herbs capable of both purging the interior and inducing sweating, dosed according to the predominance of exterior versus interior pathology. For conditions in the half-exterior/half-interior, apply harmonization. This is the treatment method for transmitted meridian diseases. For miscellaneous disease cold patterns in the exterior, use acrid-warm diaphoretics; for cold striking the interior, use intense heat remedies. It ultimately depends on clarifying the Exterior and Interior status.
Li stated: In any disease, whether there is thirst or not, vexation in the chest or not, vomiting or not, abdominal or hypochondriac pain or not, coughing or not, palpitations in the epigastrium or not, or difficulty in urination—these are all governed by the Shaoyang. Vexation or vomiting indicates the pathogen is in the exterior and about to transmit to the interior. If ear deafness, hypochondriac pain, alternating chills and fever, vomiting with bitter taste, tightness and fullness in the chest and hypochondrium, and a wiry, rapid pulse are present, this is a half-exterior/half-interior pattern. If the pulse is large, the chest is full, phlegm is abundant, or there is retained food, emesis may be used. Bai Wen states: Qi floating to the upper part, filling the chest and heart, causing headache and excessive salivation, constitutes a symptom requiring emesis. The Classic states: "For high-seated pathogens, cause them to ascend and vomit." However, even if the pulse is large, if there is no severe phlegm, emesis should not be used; only harmonization is appropriate.