（《素问·太阴阳明论》）
黄帝问曰∶太阴阳明为表里，脾胃脉也，生病而异者何也？（太阴脾也，阳明胃也，虽皆属土，然一表一里，故所
受所伤有不同矣。）岐伯对曰∶阴阳异位，更虚更实，更逆更从，或从内，或从外，所从不同，故病异名也。（脾为脏，
阴也。胃为腑，阳也。阳主外，阴主内，阳主上，阴主下，是阴阳异位也。阳虚则阴实，阴虚则阳实，是更虚更实也。
病者为逆，不病者为从，是更逆更从也。凡此者，皆所从不同，故病名亦异。）帝曰∶愿闻其异状也。岐伯曰∶阳者天气
也主外，阴者地气也主内，（胃属三阳，故主天气。脾属三阴，故主地气。）故阳道实，阴道虚。（阳刚阴柔也。又外邪多
有余，故阳道实。内伤多不足，故阴道虚。一曰阴道实则阳道虚矣，所谓更虚更实者，亦通。）故犯贼风虚邪者阳受之，
食饮不节起居不时者阴受之。阳受之则入六腑，阴受之则入五脏。（贼风虚邪，外伤也，故阳受之而入腑。饮食起居，内
伤也，故阴受之而入脏。）入六腑则身热不时卧，上为喘呼；入五脏则 满闭塞，下为飧泄，久为肠 。（不时卧，不能
以时卧也。阳邪在表在上，故为身热不卧喘呼。阴邪在里在下，故为 满飧泄肠 。 音嗔。飧音孙。 音僻。）故喉主
天气，咽主地气。（喉为肺系，所以受气，故上通于天。咽为胃系，所以受水谷，故下通于地。）故阳受风气，阴受湿气。
（风，阳气也，故阳分受之。湿，阴气也，故阴分受之。各从其类也。）故阴气从足上行至头，而下行循臂至指端；阳气
从手上行至头，而下行至足。（《逆顺肥瘦篇》曰∶手之三阴，从脏走手；手之三阳，从手走头。足之三阳，从头走足；
足之三阴，从足走腹。即此之谓。盖阴气在下，下者必升；阳气在上，上者必降。脾阴胃阳，气皆然也。）故曰阳病者上
行极而下，阴病者下行极而上。（阳病极则及于下，阴病极则及于上，极则变也。非惟上下，表里亦然。）故伤于风者，
上先受之；伤于湿者，下先受之。（阳受风气，故上先受之。阴受湿气，故下先受之。然上非无湿，下非无风，但受有先
后耳。曰先受之，则后者可知矣。）
帝曰∶脾病而四肢不用何也？岐伯曰∶四肢皆禀气于胃而不得至经，必因于脾乃得禀也。（此下言胃气必因脾气乃得
行也。）今脾病不能为胃行其津液，四肢不得禀水谷气，气日以衰，脉道不利，筋骨肌肉皆无气以生，故不用焉。（四肢
之举动，必赖胃气以为用，然胃气不能自至于诸经，必因脾气之营运，则胃中水谷之气化为精微乃得及于四肢也。若脾
病则胃气不行，故各经脉道日以衰微，而四肢不为用矣。为，去声。下同。）帝曰∶脾与胃以膜相连耳，而能为之行其津
液何也？（此下言三阴三阳之脉皆禀于脾胃之气也。膜，模、莫二音。）岐伯曰∶足太阴者三阴也，其脉贯胃属脾络嗌，
故太阴为之行气于三阴。（为之者，为胃也。脾脉贯胃属脾，足太阴也，故为之行气于三阴。三阴者，五脏之谓。）阳明
者表也，五脏六腑之海也，亦为之行气于三阳。（阳明者，太阴之表也，主受水谷以溉脏腑，故为五脏六腑之海。虽阳明
行气于三阳，然亦赖脾气而后行，故曰亦也。三阳者，即六腑也。）脏腑各因其经而受气于阳明，故为胃行其津液。（因
其经，因脾经也。脏腑得禀于阳明者，以脾经贯胃，故能为胃行其津液也。）四肢不得禀水谷气，日以益衰，阴道不利，
筋骨肌肉无气以生，故不用焉。（阴道，血脉也。此复明脾主四肢之义。）
（《素问·太阴阳明论》）
黄帝问道：足太阴脾经与足阳明胃经互为表里，分别对应脾和胃的脉象，但它们生病时表现却不同，这是什么原因呢？（足太阴属脾，足阳明属胃，虽然两者都归属于五行中的土，但一为表一为里，所以它们所感受的病邪和受到的损伤有所不同。）
岐伯回答说：阴阳二气的位置不同，虚实状态交替变化，病势或逆或顺，有的病起于内，有的病起于外，由于受病的途径不同，所以疾病的名称也不同。（脾属于脏，属阴。胃属于腑，属阳。阳主外，阴主内；阳主上，阴主下，这就是阴阳位置的不同。阳虚则阴实，阴虚则阳实，这就是虚实状态的交替。发病的是逆证，未发病的是顺证，这就是病势的逆从变化。大凡这些情况，都是因为受病的途径不同，所以疾病名称也各异。）
黄帝说：我希望了解它们不同的具体症状。岐伯说：阳气如同天气，主要主管体表；阴气如同地气，主要主管体内。（胃属于三阳经，所以主管天气。脾属于三阴经，所以主管地气。）因此，阳气的性质多实，阴气的性质多虚。（这是指阳刚阴柔的道理。另外，外来的邪气大多表现为有余之实证，所以阳道多实。内伤的疾病大多表现为不足之虚证，所以阴道多虚。还有一种说法是阴道实则阳道虚，这也就是前面所说的虚实交替，也是讲得通的。）
所以，遭受贼风虚邪等外感病邪的人，阳气先受邪；饮食不节制、起居无规律导致内伤者，阴气先受邪。阳气受邪则病入六腑，阴气受邪则病入五脏。（贼风虚邪属于外伤，所以由阳经受邪而传入腑。饮食起居失调属于内伤，所以由阴经受邪而传入脏。）
病邪进入六腑，就会出现身体发热、不能按时睡眠，向上发展为气喘呼叫；病邪进入五脏，就会出现胸腹痞满闭塞，向下发展为完谷不化的泄泻，时间久了会发展为肠澼（一种痢疾类疾病）。（“不时卧”是指不能按时入睡。阳邪在表在上，所以出现身热、不卧、气喘呼叫。阴邪在里在下，所以出现痞满、飧泄、肠澼。“嗔”音同“嗔”，“孙”音同“孙”，“僻”音同“僻”。）
所以，喉主管天气，咽主管地气。（喉是肺系的通道，用来呼吸受气，所以上通于天。咽是胃系的通道，用来吞咽水谷，所以下通于地。）
因此，阳经容易受到风邪侵袭，阴经容易受到湿邪侵袭。（风属于阳气，所以阳分容易受之。湿属于阴气，所以阴分容易受之。这是各从其类的缘故。）
阴气从足部上行至头部，然后下行沿手臂到达手指末端；阳气从手上行至头部，然后下行到达足部。（《灵枢·逆顺肥瘦篇》说：手部的三条阴经，从内脏走向手部；手部的三条阳经，从手部走向头部。足部的三条阳经，从头部走向足部；足部的三条阴经，从足部走向腹部。说的就是这个道理。大概因为阴气在下，下方的气必然上升；阳气在上，上方的气必然下降。脾阴和胃阳的气机运行都是这样的。）
所以说，阳病往往向上发展到极点转而向下，阴病往往向下发展到极点转而向上。（阳病极盛则会波及下部，阴病极盛则会波及上部，到了极点就会发生转化。不仅仅是上下如此，表里之间也是这样。）
所以，被风邪伤害的，上部先受邪；被湿邪伤害的，下部先受邪。（阳经受风气，所以上部先受邪。阴经受湿气，所以下部先受邪。然而上部并非没有湿邪，下部并非没有风邪，只是受邪有先后顺序罢了。说“先受之”，那么后受的情况就可以推知了。）
黄帝说：脾生病会导致四肢不能使用，这是什么原因呢？岐伯说：四肢都依赖胃气提供的营养，但胃气不能直接到达经脉，必须依靠脾的转输才能布达。（这部分下文要说明胃气必须借助脾气才能运行的道理。）
现在脾生病，不能为胃传输津液，四肢得不到水谷精微的营养，正气日益衰退，脉道不通畅，筋骨肌肉都没有生气来源，所以四肢就不能活动了。（四肢的动作，必须依赖胃气的作用，然而胃气不能自己到达各条经脉，必须依靠脾气的营运，将胃中水谷之气化为精微，才能到达四肢。如果脾生病，胃气就无法运行，所以各条经脉的气血日益衰微，而四肢也就不能使用了。“为”字读去声，下同。）
黄帝说：脾和胃仅通过膜相连而已，为什么脾能为胃传输津液呢？（这部分下文要说明三阴三阳的经脉都禀受脾胃之气的道理。“膜”字读模、莫两个音。）
岐伯说：足太阴脾经是三阴经之一，它的经脉贯穿胃，连属脾，联络咽喉，所以太阴脾经为三阴经传输精气。（所谓“为之”，是为胃服务。脾脉贯穿胃、连属脾，属于足太阴经，所以它为三阴经传输精气。所谓的三阴，就是指五脏。）
足阳明胃经是阳经，是五脏六腑气血汇聚的海源，它也为此为三阳经传输精气。（阳明经是太阴经的表里配合者，主管接受水谷以灌溉脏腑，所以被称为五脏六腑之海。虽然阳明经为三阳经传输精气，但也依赖脾气后才能运行，所以说“亦”。所谓的三阳，即指六腑。）
脏腑各自通过其所属的经脉从阳明胃经接受精气，所以脾能为胃传输津液。（“因其经”，是指通过脾经。脏腑之所以能禀受于阳明，是因为脾经贯穿胃，所以能为胃传输津液。）
四肢得不到水谷精微的营养，日益衰弱，阴经（血脉）不利，筋骨肌肉没有生气来源，所以四肢就不能使用了。（“阴道”指血脉。这里再次阐明脾主四肢的道理。）
(Suwen: Treatise on the Differences between Taiyin and Yangming)
The Yellow Emperor asked, "Taiyin (Spleen Meridian of Foot-Taiyin) and Yangming (Stomach Meridian of Foot-Yangming) are exterior-interior pairs, corresponding to the pulses of the Spleen and Stomach respectively. Why do they manifest different diseases?" (Taiyin belongs to the Spleen, Yangming belongs to the Stomach. Although both belong to Earth in the Five Elements, one is exterior and the other interior; therefore, the pathogenic factors they receive and the injuries they sustain differ.)
Qibo replied, "Yin and Yang occupy different positions, alternating between deficiency and excess, and between reversal and compliance. Some diseases originate internally, others externally. Because the pathways of onset differ, the names of the diseases also differ." (The Spleen is a Zang organ, belonging to Yin. The Stomach is a Fu organ, belonging to Yang. Yang governs the exterior, Yin governs the interior; Yang governs the upper, Yin governs the lower. This constitutes the difference in position between Yin and Yang. When Yang is deficient, Yin becomes excessive; when Yin is deficient, Yang becomes excessive. This is the alternation of deficiency and excess. Disease manifestation represents 'reversal' (Ni), while health represents 'compliance' (Cong). This is the alternation of reversal and compliance. All these cases arise because the pathways of onset differ, hence the disease names vary.)
The Yellow Emperor said, "I wish to hear about their specific differing symptoms." Qibo said, "Yang Qi is like Heaven's Qi, primarily governing the exterior; Yin Qi is like Earth's Qi, primarily governing the interior." (The Stomach belongs to the Three Yang meridians, thus governing Heaven's Qi. The Spleen belongs to the Three Yin meridians, thus governing Earth's Qi.) "Therefore, the pathway of Yang tends toward excess, and the pathway of Yin tends toward deficiency." (This refers to the principle that Yang is firm and Yin is soft. Furthermore, external pathogens often manifest as excess syndromes, so the Yang pathway is often solid. Internal injuries often manifest as deficiency syndromes, so the Yin pathway is often empty. Another view states that if Yin is excessive, Yang is deficient; this also aligns with the concept of alternating deficiency and excess mentioned earlier.)
Thus, those who contract thievish winds and empty evils (external pathogens) are affected by Yang first; those whose diet is irregular and daily routine unregulated are affected by Yin first. When Yang is affected, the pathogen enters the Six Fu organs; when Yin is affected, the pathogen enters the Five Zang organs. (Thievish winds and empty evils are external injuries, so they are received by Yang and enter the Fu organs. Diet and daily routine irregularities are internal injuries, so they are received by Yin and enter the Zang organs.)
When entering the Six Fu organs, it results in fever and inability to sleep at proper times, progressing upward to panting and calling out; when entering the Five Zang organs, it results in abdominal fullness and obstruction, progressing downward to undigested stool diarrhea (Sun-xie), and over time to intestinal dysentery (Chang-bi). ("Inability to sleep at proper times" means not being able to sleep according to the natural rhythm. Yang pathogens in the exterior and upper levels cause fever, insomnia, panting, and calling out. Yin pathogens in the interior and lower levels cause fullness, Sun-xie, and Chang-bi. 'Chen' sounds like 'chēn', 'Sun' sounds like 'sūn', 'Pi' sounds like 'pì'.)
Therefore, the throat governs Heaven's Qi, and the pharynx governs Earth's Qi. (The throat is the connection of the Lung system, used for receiving Qi, thus connecting upward to Heaven. The pharynx is the connection of the Stomach system, used for swallowing food and water, thus connecting downward to Earth.)
Consequently, Yang meridians are susceptible to Wind pathogens, and Yin meridians are susceptible to Dampness pathogens. (Wind is Yang Qi, so it is received by the Yang aspect. Dampness is Yin Qi, so it is received by the Yin aspect. This follows the principle of similarity.)
Yin Qi ascends from the feet to the head, then descends along the arms to the fingertips; Yang Qi ascends from the hands to the head, then descends to the feet. (The *Ling Shu: Chapter on Reverse, Smooth, Fat, and Thin* states: The three Yin meridians of the hand travel from the Zang organs to the hands; the three Yang meridians of the hand travel from the hands to the head. The three Yang meridians of the foot travel from the head to the feet; the three Yin meridians of the foot travel from the feet to the abdomen. This is what is meant. Generally, Yin Qi is below, and Qi from below must ascend; Yang Qi is above, and Qi from above must descend. The movement of Spleen Yin and Stomach Yang Qi follows this pattern.)
Therefore, it is said that Yang diseases tend to move upward to an extreme and then downward, while Yin diseases tend to move downward to an extreme and then upward. (When Yang disease reaches its extreme, it affects the lower part; when Yin disease reaches its extreme, it affects the upper part. Extremes lead to transformation. This applies not only to up and down but also to exterior and interior.)
Thus, those injured by Wind are affected on the upper part first; those injured by Dampness are affected on the lower part first. (Yang meridians receive Wind, so the upper part is affected first. Yin meridians receive Dampness, so the lower part is affected first. However, the upper part is not devoid of Dampness, nor is the lower part devoid of Wind; there is merely a sequence of reception. To say 'affected first' implies the order of subsequent reception.)
The Yellow Emperor asked, "Why does Spleen disease result in the inability to use the four limbs?" Qibo replied, "The four limbs all derive their Qi from the Stomach, but Stomach Qi cannot reach the meridians directly; it must rely on the Spleen to be distributed." (The following text explains that Stomach Qi must rely on Spleen Qi to function.)
"Now, when the Spleen is diseased and cannot transport fluids and essence for the Stomach, the four limbs do not receive Water-God Qi (nutritive essence from food and drink). Qi declines day by day, the meridians become obstructed, and the sinews, bones, muscles, and flesh lack the source of Qi to generate vitality, resulting in dysfunction." (The movement of the four limbs relies on Stomach Qi. However, Stomach Qi cannot reach the various meridians on its own; it requires the Spleen's transportation to transform the Qi of food and drink in the Stomach into refined essence, which then reaches the four limbs. If the Spleen is diseased, Stomach Qi fails to circulate, causing the meridians to decline daily, and the four limbs lose their function. The character 'Wei' is pronounced with the departing tone, same as below.)
The Yellow Emperor asked, "The Spleen and Stomach are connected only by membranes; why can the Spleen transport fluids for the Stomach?" (The following text explains that the meridians of the Three Yin and Three Yang all derive from the Qi of the Spleen and Stomach. 'Membrane' is pronounced as 'mo' or 'mò'.)
Qibo replied, "Foot-Taiyin is one of the Three Yin meridians. Its vessel penetrates the Stomach, connects to the Spleen, and links to the pharynx; therefore, Taiyin transports Qi to the Three Yin meridians." (What 'transports for it' means is transporting for the Stomach. The Spleen vessel penetrates the Stomach and connects to the Spleen, belonging to Foot-Taiyin; thus, it transports Qi to the Three Yin meridians. The Three Yin refer to the Five Zang organs.)
"Foot-Yangming is the exterior meridian and the Sea of the Five Zang and Six Fu organs; it also transports Qi to the Three Yang meridians." (Yangming is the exterior counterpart of Taiyin, governing the reception of food and drink to nourish the Zang and Fu organs, hence called the Sea of the Five Zang and Six Fu organs. Although Yangming transports Qi to the Three Yang meridians, it also relies on Spleen Qi to function, hence the word 'also'. The Three Yang refer to the Six Fu organs.)
"The Zang and Fu organs each receive Qi from Yangming through their respective meridians; therefore, [the Spleen] transports fluids for the Stomach." ('Through their respective meridians' refers to the Spleen meridian. The Zang and Fu organs receive from Yangming because the Spleen meridian penetrates the Stomach, enabling it to transport fluids for the Stomach.)
"When the four limbs do not receive Water-God Qi, they decline increasingly. The Yin vessels (blood vessels) become obstructed, and the sinews, bones, muscles, and flesh lack Qi to generate vitality, resulting in dysfunction." ('Yin vessels' refers to blood vessels. This reiterates the principle that the Spleen governs the four limbs.)