肺居西方金位。上应阳明燥令。其与足太阴脾同名太阴者。以其为一身元气之主。出治节以佐君。其位居华盖之顶。
其职与太阴脾。同行气以给众脏。故名之也。而其实为阳中之少阴。主秋令以成万物。秋令清肃 敛。肺以丽水之金。
生形而居天河之上源。以沛雨露。故尝病躁与寒热。最为娇脏也。其气恒下行。静则下沉于肾宫。而与水相通。所谓母
隐子胎也。以其外应皮毛。皮毛属太阳之部。故太阳之伤风伤寒。与汗出中风。兼形寒饮冷。皆伤肺见症。如鼻塞声重。
气逆喘嗽。肩背痛。嚏呕胸满烦心等证。多与太阳同。至若五志之火上炎。阴虚内铄。肝火抉心而刑金。则亦伤肺。其
证为肺痈、肺痿、痿 、吐血、声嘶、息有音、鼽衄、掌中热、喘不休、白血出、皮毛焦。此皆火燥焦枯之症。虚则少
气。不能报息。耳聋嗌干。治之之法。伤于外者。与足太阳同法。其邪气盛。而闭塞愤郁。必于足太阳泻之。伤于内者。
正气衰而金被伤。必于足少阴养之。而于足太阴培之。补水培土。养金之善法也。然以金性下沉。隐于子胎。肾家水火
两病。亦能使肺两症同受。故有时水泛而为喘壅。有时水沸而为痰鸣。皆以气上逆。而有水火虚实之不同。而要其治。
总不出足太阳及少阴太阴三经之法耳。
肺位于西方金位。上对应阳明燥气的时令。它与足太阴脾同名“太阴”的原因，是因为它是全身元气的主宰，发出治节（治理调节）的功能来辅佐君主（心）。它的位置处于华盖（指肺部覆盖五脏的形态）的顶端。
它的职能与足太阴脾相同，共同运行气机以供给各个脏腑，所以名称相同。而实际上它属于阳中的少阴，主管秋令以成就万物。秋令气候清肃收敛。肺如同丽水之金，生成形体并居于天河（指人体上部气血运行的通道）的上源，以沛降雨露（比喻津液的输布）。因此肺容易患躁动和寒热的病证，是最为娇嫩的脏器。
肺的气机通常下行，静止时下沉于肾宫，从而与水相通。这就是所谓的“母隐子胎”（肺为肾之母，母子相生相藏）。因为肺外应皮毛，而皮毛属于太阳经的部属，所以太阳经受邪引起的伤风、伤寒，以及汗出后中风，兼有形体受寒、饮食生冷等情况，都会损伤肺而出现症状。如鼻塞声音重浊、气逆喘咳、肩背部疼痛、打喷嚏呕吐、胸满心烦等证候，大多与太阳经病相似。至于五志之火向上炎升，阴虚导致内部灼热，肝火挟带心火来克制肺金，也会损伤肺。其证候表现为肺痈、肺痿、肢体痿软、吐血、声音嘶哑、呼吸有声、鼻流清涕或衄血、手掌心发热、喘促不止、咳出白色泡沫痰、皮毛枯焦。这些都是火燥导致焦枯的症状。肺气虚弱则少气，不能深长呼吸，耳聋咽干。治疗的方法：如果是外邪所伤，方法与足太阳经相同。如果邪气盛实，导致闭塞愤郁，必须在足太阳经进行泻法。如果是内伤所致，正气衰弱且肺金被伤，必须在足少阴经进行滋养，并在足太阴经进行培补。补水培土，是养金的善法。然而由于金的性质下沉，隐伏于子（肾）胎之中，肾家的水火两方面的病变，也能使肺同时受到两种病症的影响。所以有时水湿泛滥导致喘促壅塞，有时水沸（虚火上炎）导致痰鸣，都是因为气机上逆，而有水火虚实性质的不同。但总括其治疗原则，总离不开足太阳、足少阴、足太阴这三条经脉的治疗方法。
The Lung resides in the West, corresponding to the Metal position. It corresponds superiorly to the Yangming dryness climate. Its shared name "Taiyin" (Greater Yin) with the Foot-Taiyin Spleen is because it serves as the master of the body's primordial Qi, issuing regulatory functions (Zhi Jie) to assist the Sovereign (Heart). Its location is at the apex of the "Huagai" (Canopy, referring to the Lung covering the other organs).
Its function is identical to that of the Foot-Taiyin Spleen: both circulate Qi to supply the various Zang organs, hence their shared name. However, essentially, it belongs to Shao Yin (Lesser Yin) within Yang, governing the Autumn season to complete all things. The Autumn climate is clear,肃 (solemn/clear), and contracting. The Lung, like Metal from Lishui, generates form and resides at the upper source of the Heavenly River (referring to the upper pathways of Qi and Blood), distributing rain and dew (metaphor for the dissemination of Body Fluids). Therefore, it is prone to disorders of restlessness and alternating cold and heat, making it the most delicate organ.
Its Qi naturally descends; when still, it sinks into the Kidney Palace, connecting with Water. This is referred to as "the Mother hiding in the Child's womb" (Lung is the Mother of Kidney, implying mutual generation and storage). Because the Lung externally corresponds to the Skin and Hair, which belong to the Taiyang (Greater Yang) domain, injuries to Taiyang such as Wind Strike (Shang Feng), Cold Damage (Shang Han), wind invasion after sweating, combined with external cold exposure or consumption of cold drinks, all damage the Lung and manifest symptoms. These include nasal congestion with heavy voice, rebellious Qi with wheezing and cough, shoulder and back pain, sneezing with vomiting, chest fullness, and vexation. Such syndromes are largely similar to Taiyang disorders.
However, if the Fire of the Five Emotions flares upward, or Yin deficiency causes internal burning, or Liver Fire joins Heart Fire to attack Metal (Lung), the Lung is also damaged. Manifestations include Lung Abscess (Fei Yong), Lung Withering (Fei Wei), flaccidity syndrome (Wu Zhong), hemoptysis, hoarseness, noisy respiration, rhinorrhea or epistaxis, heat in the palms, incessant wheezing, expectoration of white sputum, and withered skin and hair. These are all symptoms of scorching and drying due to Fire and Dryness. Deficiency leads to shortness of breath and inability to complete inhalation, deafness, and dry throat.
The treatment method: For external injury, the approach is the same as for the Foot-Taiyang Bladder channel. If pathogenic Qi is excessive, causing obstruction and stagnation, purgation must be applied to the Foot-Taiyang channel. For internal injury, where Righteous Qi is deficient and Metal (Lung) is damaged, nourishment must be applied to the Foot-Shaoyin Kidney channel, and tonification to the Foot-Taiyin Spleen channel. Nourishing Water and cultivating Earth are excellent methods for supporting Metal.
However, since the nature of Metal is to sink and hide in the Child's (Kidney's) womb, diseases of both Water and Fire in the Kidney can cause the Lung to suffer from dual pathologies. Thus, sometimes water flooding leads to wheezing and oppression; sometimes boiling water (deficient fire) leads to phlegm rales. All result from rebellious Qi ascending, differing in terms of Water/Fire and Excess/Deficiency. Nevertheless, the general treatment principle never deviates from the methods of the Foot-Taiyang, Foot-Shaoyin, and Foot-Taiyin channels.