表里俱病者，俱伤于邪也，非表邪实、里正虚之谓也。气者，六淫是也。试以寒热明其
例。
表里俱寒者，治宜温中以散寒，里气壮而外邪可退矣。仲景于身体疼痛，下利清谷，先
温其
里，后攻其表者，是指示大法如此。其实表里两感于寒，温里、发表，一时并用，正不必分
先后也。
表里俱热者，治宜甘寒，佐以辛凉解散，如叶香岩温热治法。若阳明腑实者，更先以苦
寒咸
寒攻下之，如服承气，大便得通，而汗自出是也。二者表里同气。故重在里，治其里而表亦
即应手而愈矣。即或表有未尽余邪，再略清其表可也。若先攻其表，不但里虚，而表不能净
；即令表净，而正气受伤，里邪又将从何路以驱除之?
表热里寒者，如其人素属中寒，而新感风热，治宜解表而已。如其人内伤生冷，外伤风
热，表里俱属新邪，则治宜辛凉疏表之中，佐以芳香理气，以化内寒。
表寒里热者，如其热是因表邪，腠理闭遏所致，但解表而已。如其热是因温邪蕴结，而
表又
新感风寒，轻者辛凉疏其里热，而外寒自祛；重者寒力足蔽其热，治宜辛香轻悍，急通其表
，免致表邪久束，里热愈深，渍入经络，沾滞血分，便难措手，但剂中宜佐凉滋，不可过燥
，表解急清里热。二者表里异气，故重在表，所谓先攻其易也。若先攻里，不但表邪内陷，
恐里邪未易去，而表邪已坚矣。此法之大体也。又当随时消息病势之缓急，以为施治之先后
，神明于法中，而非死板法也。其庶几乎?
大抵病由外陷内者，须开其表而撑其里，使邪仍从原路出也。昔人尝谓∶少阴之邪，仍
以太
阳为出路；太阳之邪，仍以阳明为出路。故凡外邪内陷日久者，服药后能转见表证，即是邪
气退出也。又如内伤饮食，以致恶寒，则攻滞之中，必兼理气；内伤精血，以致发热，则养
阴之中，必寓潜阳。此又表里互虚、互实之治法也。
表证和里证同时存在的，是指表里两方面的正气都受到了邪气的伤害，并不是指表邪盛实而里气正虚的情况。这里所说的“气”，指的是六淫（风、寒、暑、湿、燥、火六种外感病邪）。试以寒证和热证为例来说明。
表里俱寒的，治疗应当温补中焦以驱散寒邪，只要里气强壮，外邪自然可以退去。张仲景在遇到身体疼痛、下利清谷（大便中有未消化的食物）的情况下，主张先温补里气，后解除表邪，这是指示了大的治疗法则。其实，如果是表里同时感受寒邪，温里和解表的方法可以同时使用，并不一定非要分先后顺序。
表里俱热的，治疗应当用甘寒之法，辅以辛凉解散的方法，就像叶天士治疗温热病的方法那样。如果是阳明腑实证，更应当先用苦寒或咸寒的药物攻下，比如服用承气汤，等到大便通畅，汗液自然就会排出。这两种情况属于表里同气（性质相同）。所以治疗重点在于里，治好了里证，表证也会随即痊愈。即使表部还有未尽的余邪，再稍微清解一下表邪就可以了。如果先攻解表邪，不但会导致里气更虚，而且表邪也不能彻底清除；即使表邪清除了，但正气已经受伤，里的邪气又该通过什么途径来驱除呢？
表热里寒的，如果这个人平时就属于中焦虚寒，又新近感染了风热，治疗只需解表即可。如果这个人内伤于生冷饮食，外伤于风热，表里都属于新受的邪气，那么治疗应当在辛凉疏解表邪的同时，辅以芳香理气的药物，以化解内部的寒邪。
表寒里热的，如果这个热是因为表邪导致腠理闭塞而引起的，只需解表即可。如果这个热是因为温邪蕴结在内，而体表又新近感受了风寒，轻症时，用辛凉药物疏通内部的里热，外部的寒邪自然会被祛除；重症时，寒邪的力量足以掩盖住里热，治疗应当用辛香轻扬峻猛的药物，迅速开通表邪，以免表邪长期束缚，导致里热更深，浸渍进入经络，粘滞于血分，那时就很难处理了。但在药方中应当佐以清凉滋润的药物，不可过于燥烈，待表邪解除后，立即清解里热。这两种情况属于表里异气（性质不同），所以治疗重点在于表，这就是所谓的“先攻其易”（先解决容易解决的表邪）。如果先攻治里证，不但会导致表邪内陷，恐怕里的邪气也不容易去除，而表邪却已经坚固难解了。这是这种方法的大致原则。另外，还应当随时斟酌病势的缓急，来决定治疗的先后顺序，在法则中灵活运用，而不是死板地套用方法。这样差不多就可以了吧？
大抵疾病由外部陷入内部的，必须开通表邪并扶持里气，使邪气仍然从原来的路径排出。前人曾说：少阴经的邪气，仍以太阳经作为出路；太阳经的邪气，仍以阳明经作为出路。所以凡是外邪内陷时间较长的，服药后如果能重新出现表证，就是邪气退出的表现。又如因内伤饮食而导致恶寒的，在攻逐积滞的同时，必须兼有理气的作用；因内伤精血而导致发热的，在滋养阴液的同时，必须寓含潜阳的作用。这又是表里互虚、互实的治疗法则。
When both exterior and interior syndromes are present, it means that the righteous qi (Zheng Qi) of both levels has been injured by pathogenic factors; it does not refer to a situation where exterior pathogens are excess and solid while interior righteous qi is deficient. The "qi" mentioned here refers to the Six Excesses (Liu Yin: Wind, Cold, Summerheat, Dampness, Dryness, Fire). Let us clarify this with examples of Cold and Heat.
In cases of simultaneous exterior and interior Cold, treatment should focus on warming the Middle Jiao to disperse Cold. Once the interior righteous qi is strengthened, the exterior pathogens can be repelled. Zhang Zhongjing, in cases involving body pain and diarrhea with undigested food (Xia Li Qing Gu), advocated first warming the interior and then attacking the exterior. This indicates the general principle of treatment. In reality, when both exterior and interior are simultaneously affected by Cold, methods for warming the interior and releasing the exterior can be used concurrently, without necessarily requiring a strict sequence.
In cases of simultaneous exterior and interior Heat, treatment should employ Sweet-Cold methods, assisted by Pungent-Cool methods to dissipate and resolve, similar to Ye Tianshi's approach to treating Warm Diseases. If there is Yangming Fu-organ excess syndrome, one should first use Bitter-Cold or Salty-Cold purgatives, such as administering Chengqi Tang. Once the stool becomes unobstructed, sweat will naturally occur. These two scenarios involve the same nature in both exterior and interior (Biao Li Tong Qi). Therefore, the emphasis is on the interior; treating the interior will cause the exterior symptoms to resolve promptly. Even if some residual exterior pathogens remain, a slight clearing of the exterior suffices. If one attacks the exterior first, it will not only further weaken the interior but also fail to completely clear the exterior pathogens; even if the exterior is cleared, the righteous qi will be damaged, leaving no proper pathway to expel the interior pathogens.
In cases of exterior Heat and interior Cold, if the patient constitutionally suffers from Middle Jiao Cold and has recently contracted Wind-Heat, treatment requires only releasing the exterior. If the patient has suffered internal injury from raw/cold foods and external injury from Wind-Heat, meaning both exterior and interior involve newly acquired pathogens, treatment should combine Pungent-Cool methods to疏解 (release/disperse) the exterior with Aromatic methods to regulate Qi and transform interior Cold.
In cases of exterior Cold and interior Heat, if the heat is caused by the closure of Cou Li (pores/skin texture) due to exterior pathogens, simply releasing the exterior is sufficient. If the heat is due to the accumulation of Warm pathogens internally, compounded by a new contraction of Wind-Cold externally, mild cases can be treated with Pungent-Cool methods to vent interior Heat, causing external Cold to dispel spontaneously. In severe cases, the power of Cold may mask the Heat; treatment should utilize light, penetrating, and vigorous Pungent-Aromatic agents to rapidly open the exterior. This prevents the exterior pathogens from binding for long, which would drive interior Heat deeper, infiltrating the meridians and stagnating in the Blood level, making treatment difficult. However, cooling and moistening agents should be added to the prescription to avoid excessive dryness; once the exterior is resolved, interior Heat must be cleared immediately. These two scenarios involve different natures in exterior and interior (Biao Li Yi Qi); thus, the emphasis is on the exterior, following the principle of "attacking the easier target first." If one attacks the interior first, it risks driving exterior pathogens inward; moreover, the interior pathogens may not be easily eliminated, while the exterior pathogens become entrenched. This outlines the general framework of this method. Furthermore, one must constantly assess the urgency of the disease progression to determine the sequence of treatment, applying wisdom within the rules rather than rigidly adhering to fixed formulas. Is this not the way?
Generally, when diseases sink from the exterior to the interior, one must open the exterior and support the interior, allowing pathogens to exit via their original pathway. Ancients stated that Shaoyin pathogens still use the Taiyang channel as an exit route; Taiyang pathogens still use the Yangming channel as an exit route. Therefore, in cases of prolonged interior sinking of exterior pathogens, if symptoms reappear at the exterior level after medication, it indicates the expulsion of pathogens. Similarly, if Chills result from dietary injury, resolving stagnation must be accompanied by regulating Qi; if Fever results from injury to Essence and Blood, nourishing Yin must incorporate subduing Yang. These represent the treatment methods for mutual deficiency and excess between exterior and interior.