【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。
【纲】张仲景说：患伤寒病五六天，出现头痛、出汗、轻微怕冷、手脚发凉、胃脘部胀满、不想吃东西、大便干硬、脉象沉细的情况，这叫做“阳微结”（阳气轻微郁结）。这必定既有表证又有里证。脉象沉，说明病位在里。出汗是因为阳气轻微郁结。假如是纯粹的阴寒内结，就不会再有体表的症状，所有症状都完全入里了。这是病邪一半在表、一半在里的表现。虽然脉象沉细，但不能诊断为少阴病。之所以这样判断，是因为阴证通常不会有汗出，现在头部出汗，所以知道这不是少阴病。可以给予小柴胡汤治疗。如果服药后病情仍不舒畅，通过排便就能痊愈。
【目】成无己说：邪气客居在体表的是寒邪，邪气与阳气相争就会表现为恶寒；邪气侵入体内的属于热邪，邪气与阴气相争就会表现为发热。邪气在半表半里之间，向外与阳气相争就表现为恶寒，向内与阴气相争就表现为发热。因此出现忽冷忽热的症状。邪气在体表较多则恶寒明显，邪气在体内较多则发热明显。邪气一半在表一半在里，那么寒热症状也就各占一半。邪气在体表的，必须通过浸渍形体来发汗；邪气在体内的，必须通过荡涤肠胃来通便泻下。其余既不在表也不在里，处于半表半里的情况，又不适合发汗，也不是催吐或攻下的对症方法，应当采用和解的方法即可，比如小柴胡汤就是这类方剂。
戴原礼说：医书中有的提到太阳经病，有的提到太阴经病；有的称为伤寒，有的称为中风；有的只称厥逆，有的只称下利；有的只称某病，有的只称某经。这是因为邪气中伤于某条经脉，所以以经脉名称来命名它，不仅仅是指伤寒的证候，还指兼有杂病的情况。凡是只说伤寒而不提具体经脉的，就不是单纯的杂病，而是指六经都可能出现的所有症状，难以用一条经脉来拘泥限定，中风也是如此。凡是提到下利及厥逆，以及称呼病患等名称的症状，是指六经病、伤寒、中风、杂病等各种证候中都可能出现的症状。善于治病的人，必须详细辨别。无论是太阳传经而来的邪气，还是各经直中的邪气，无论是曾经没有经过汗、吐、下治疗的病症，还是火逆、水喷的病症，或者是结胸、发黄、血滞、痞满下利、厥逆的病症，以及中风、伤寒、杂病的各种证候，所有的疾病，不拘泥于六经，只需分辨表里。大概六经都有表里两种症状，只要有表证，就用发汗法；只要有里证，就用攻下法。如果表里症状同时出现，就适宜使用既能攻里又能发汗的药物，根据表里病症的轻重比例来用药。病在半表半里的，用和解法治疗。这是治疗传经病的方法。杂病中的寒证如果在体表，用辛温药发汗；寒邪中于体内的，用大热药救治。这也在于明确其表里而已。
李曰：凡是生病，或者口渴或者不渴，或者心中烦闷或者不烦闷，或者呕吐或者不呕吐，或者腹部胁肋疼痛或者不疼痛，或者咳嗽，或者心下悸动，或者小便不利，这些都是少阳经所主司的症状。或者烦闷或者呕吐的，是邪气在体表，正要传入体内的表现。如果出现耳聋、胁痛、寒热往来、呕吐且口苦、胸胁紧绷胀满、脉象弦数，这就是半表半里的证候。如果脉象大、胸部胀满、痰多，或者夹杂宿食，可以用吐法。《百问》中说：气浮于上部，填塞心胸，头痛且多涎，这是应当用吐法的症状。《内经》说：病位在高处的，顺势使其涌越而出。但如果脉象虽大，却没有严重的痰浊，就不可以用吐法，只适宜用和解法。
[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.