脏腑内景，各有区别。咽喉二窍，异途施化。喉在前，其质坚空，连接肺本，通呼吸之气，分布
于五脏，为气息之要道∶咽在后，其质柔空，下按胃本，水谷由此而入胃，乃运粮之关津。二道并行，
各不相犯。盖饮食必历气口而下，气口有一会厌，当饮食方咽，会厌即垂，气口乃闭，故水谷下咽，
不混入喉。若言语呼吸，则会厌开张，所以当饮食言语，水谷乘气送入喉管，遂呛而咳矣。喉下为肺，附
着脊之第三椎。肺形四垂，六叶白莹，谓为华盖，以复诸脏，虚如蜂窠，呼之则虚，吸之则满，上通于
鼻，下无透窍。肺之下有心，附着脊之第五椎。心有系络，上联于肺，其象尖圆，形如莲蕊，其中有窍，
多寡不同，上通于舌，下无透窍，其脾肝肾三脏，各有一系，上透膈膜，以通于心，外有赤黄裹脂，是
为心胞络，此即膻中，故经言膻中为心主之宫城。心下有膈膜，与脊胁相着，遮蔽浊气，使不得上
熏心肺。膈膜之下有脾，当十一椎下。脾膜连着于胃，形如刀镰，闻声则动，动则摩胃，食乃消化。
有系上通于心，开窍于脾之下。左有肝，着脊之十三椎下。肝有七叶，亦有二、三叶者，有独叶者。亦
有系，上通于心，开窍于目，下亦无窍。肝之短叶间，有胆附焉。胆有汁，主藏而不泻。肝
之下有肾，附于脊之第十四椎下。肾有两枚，形如豇豆，相并而曲，附于脊之两旁，相去各一寸五
分。外有黄脂包裹，俱通脊中，上至髓海，下至尾 。亦各有一系，上系则通于心，下系则通精窍，
开窍于二阴。两肾之前，膀胱之后，出大肠之上左，居小肠之下右，是谓命门，又曰子宫，〔即
经所谓胞中也。〕在男则为精室，在女则为血室。〔胞胎系此。〕两肾俱属水，但左属阴，右属阳，
越人谓左为肾，右为命门，非也。命门即两肾之中，通肾之下系，为相火，一阳处二阴之间，所以成
乎坎也。此喉之一窍，施气运化，熏蒸流行，以成脉胳者如此。咽通胃脘，胃之上脘，名曰贲门，饮
食之精气，从此输脾达肺，宣布于诸脉；胃之中脘，盛受水谷，而腐熟之。胃之下，左有小肠，小肠
上口即胃之下脘，名曰幽门，前附脐上二寸，后附于脊，水谷由此而入。左回叠积十六曲，小肠下口
，即大肠之上口，名曰阑门，至是而泌别清浊，水液渗入膀胱，滓秽传入大肠。大肠居胃之下，右当脐
，左回亦十六曲，故曰回肠。广肠即回肠之更大者，附脊，以受回肠之渣滓。左环叠积，以下直肠，
抵肛门，总名大肠。膀胱当十九椎，居肾之下，广肠之前，有下口，无上口。水液由此别回肠随气
渗入，下连前阴，溺之所出；其入其出，皆由气化。此咽之一窍，资生气血，转化糟粕而入出者如此。
三焦者，上焦处于膈膜之上，主纳，纳而不出，经言上焦如雾者，宗气积于胸中，如天之雾也。中焦当
胃之中脘，主腐熟水谷，中焦如沤者，言荣血化于中焦，随气流行，以奉生身，如水泡处浮沉之间也。
下焦起于阑门之下，主出而不纳，下焦如渎者，如川渎之水，逝而不返也。学人但能熟此，则脏腑
之内景，便照然于心目矣。
The internal structures of the Zang-Fu organs (Viscera) differ from one another. The throat (Hou) and pharynx (Yan) are two orifices that function via different pathways. The throat is located anteriorly, with a firm yet hollow texture, connecting to the root of the Lung (Fei), governing the Qi of respiration, and distributing to the five Zang organs; it serves as the critical pathway for breath. The pharynx is located posteriorly, with a soft yet hollow texture, extending downward to connect to the root of the Stomach (Wei); food and fluids enter the stomach through it, serving as the passageway for nourishment. These two channels run parallel without interfering with each other. Generally, food and drink must descend through the air passage (Qi Kou). At this passage lies the epiglottis (Hui Yan); when swallowing begins, the epiglottis droops to close the air passage, ensuring that food and fluids do not mix into the throat. However, during speech or breathing, the epiglottis opens. Therefore, if one speaks while eating, food may be carried by the airflow into the trachea, causing choking and coughing.
Below the throat lies the Lung, attached to the third thoracic vertebra of the spine. The Lung has a hanging shape with six lobes, white and lustrous, referred to as the "Canopy" (Hua Gai) because it covers and protects the other organs. Its interior is spongy like a honeycomb; it becomes empty upon exhalation and full upon inhalation. It connects superiorly to the nose but has no opening inferiorly. Below the Lung lies the Heart (Xin), attached to the fifth thoracic vertebra. The Heart is connected by ligaments to the Lung superiorly. It is pointed and round, resembling a lotus stamen, with varying numbers of orifices inside. It connects superiorly to the tongue but has no opening inferiorly. The Spleen (Pi), Liver (Gan), and Kidney (Shen) each have a ligamentous connection penetrating the diaphragm to communicate with the Heart. Externally, they are wrapped in yellowish fat, forming the Pericardium (Xin Bao Luo), also known as the Tan Zhong (Chest Center). Thus, the classics state that the Tan Zhong is the palace city of the Heart.
Below the Heart is the diaphragm, adhering to the spine and ribs, which blocks turbid Qi from ascending to smoke the Heart and Lungs. Below the diaphragm lies the Spleen, positioned below the eleventh thoracic vertebra. The Spleen's membrane connects to the Stomach, shaped like a sickle; it moves upon hearing sounds, rubbing against the Stomach to aid digestion. It has a ligament connecting upward to the Heart and an opening below the Spleen itself. To the left is the Liver, attached below the thirteenth thoracic vertebra. The Liver typically has seven lobes, though some have two, three, or even a single lobe. It also has a ligament connecting upward to the Heart, opens into the eyes, and has no inferior opening. Between the short lobes of the Liver attaches the Gallbladder (Dan). The Gallbladder contains bile and functions primarily to store rather than excrete.
Below the Liver lie the Kidneys, attached below the fourteenth thoracic vertebra. There are two Kidneys, shaped like kidney beans, curved and adjacent, attached to both sides of the spine, each about 1.5 cun apart. They are wrapped externally in yellow fat and connect to the spinal marrow, extending up to the Sea of Marrow and down to the tailbone. Each Kidney has a ligament: the upper one connects to the Heart, and the lower one connects to the essence orifice, opening at the two yin orifices (urethra and anus). Located anterior to the two Kidneys, posterior to the Bladder, superior to the large intestine on the left, and inferior to the small intestine on the right, is the Gate of Life (Ming Men), also called the Uterus (Zi Gong) [which refers to the Bao Zhong mentioned in the classics]. In males, this is the chamber of essence; in females, it is the chamber of blood [where the fetus is anchored]. Both Kidneys belong to Water, but the left belongs to Yin and the right to Yang. Yue Ren (Bian Que) claimed the left is the Kidney and the right is the Ming Men, which is incorrect. The Ming Men is situated between the two Kidneys, connecting to the lower ligament of the Kidneys, serving as the Minister Fire (Xiang Huo). With one Yang line situated between two Yin lines, it forms the Kan hexagram. This describes how the throat orifice facilitates Qi transformation, steaming and circulating to form the meridians.
The pharynx connects to the Wei Guan (Stomach region). The upper part of the Stomach is named the Fen Men (Cardia); the essence of food and drink is transported here to the Spleen and then to the Lung, spreading through the vessels. The middle part of the Stomach receives and ripens food and fluids. Inferior to the Stomach, on the left, is the Small Intestine. Its upper opening is the lower part of the Stomach, named the You Men (Pylorus), located anteriorly 2 cun above the umbilicus and posteriorly against the spine, where food and fluids enter. The Small Intestine loops back sixteen times on the left. Its lower opening is the upper opening of the Large Intestine, named the Lan Men (Ileocecal Valve). Here, clear and turbid substances are separated; fluid seeps into the Bladder, while waste enters the Large Intestine.
The Large Intestine is located below the Stomach, aligned with the umbilicus on the right, and looping back sixteen times on the left, hence called the Hui Chang (Returning Intestine). The Guang Chang (Rectum) is the larger continuation of the Hui Chang, attached to the spine, receiving residue from the returning intestine. It loops to the left, descends straight to the anus, and is collectively termed the Large Intestine. The Bladder is located at the nineteenth thoracic vertebra, below the Kidneys and anterior to the rectum. It has a lower opening but no upper opening. Fluids separate from the Hui Chang and seep in according to Qi movement, connecting inferiorly to the external genitalia as the exit for urine; both entry and exit are governed by Qi transformation. This describes how the pharynx orifice aids in generating Qi and Blood, transforming waste for excretion.
Regarding the San Jiao (Triple Burner): The Upper Burner is above the diaphragm, governing reception without excretion. The classics state "The Upper Burner is like mist," referring to Zong Qi (Gathering Qi) accumulating in the chest, resembling heavenly mist. The Middle Burner corresponds to the middle of the Stomach, governing the ripening of food and fluids. "The Middle Burner is like a fermenting vat" indicates that Ying Blood (Nutritive Blood) is generated in the Middle Burner, circulating with Qi to nourish the body, similar to bubbles floating in water. The Lower Burner begins below the Lan Men, governing excretion without reception. "The Lower Burner is like a ditch" signifies water flowing in a river channel, moving forward without returning. If students master these details, the internal landscape of the Zang-Fu organs will become clear in their minds and eyes.