四十难曰∶经言肝主色，心主臭，脾主味，肺主声，肾主液。鼻者肺之候，而
反知香臭；耳者肾之候，而反闻声。其意何也？
然∶肺者，西方金也，金生于巳，巳者，南方火
也，火者心，心主臭，故令鼻知香臭；肾者，北方水也，水生于申，申者，西方金，金者肺，肺
主声，故令耳闻声。
此五主，《素》《灵》无考，是摭古医经者。陈氏曰∶臭者心所主，鼻者肺之窍，心之脉上肺，
故令鼻能知香臭也。耳者肾之窍，声者肺所主，肾之脉上肺，故令耳能闻声也。或谓此以五行长生
之法推之，木长生于亥，火长生于寅，金长生于巳，水长生于申。心主臭，火也，肺开窍于鼻而有
己火，故能知臭。肺主声，金也，肾水开窍于耳，而内有申金，故能闻声。
四十一难曰∶肝独有两叶，以何应也？
然∶肝者，东方木也，木者，春也。万物之始生，其尚幼
小，意无所亲，去太阴尚近，离太阳不远，犹有两心，故有两叶，亦应木叶也。
肝有两叶，应东方之木，木者春也，万物始生之初，草木甲坼，皆两叶，乃木之本体，故肝
与之相应也。《素问·六节藏象论》言心为阳中之太阳，肾为阴中之太阴，肾水为肝之母，心火为
肝之子，肝为阴中之阳，居肾之上，心之下，故云尚近不远也。无亲，谓不专属。犹有两心，言或
从乎阳，或从乎阴也。
第四十难说：医经中说肝主管颜色，心主管气味，脾主管味道，肺主管声音，肾主管体液。鼻子是肺的外候，却反而能辨别香臭；耳朵是肾的外候，却反而能听到声音。这是什么意思呢？
回答说：肺属西方金，金生于巳（地支），巳属南方火，火对应心，心主管气味，所以使鼻子能辨别香臭；肾属北方水，水生于申（地支），申属西方金，金对应肺，肺主管声音，所以使耳朵能听到声音。
这五种“主”的关系，《素问》和《灵枢》中没有考证依据，这是摘取古代医经的说法。陈氏说：气味由心所主，鼻子是肺的窍，心的经脉上行至肺，所以使鼻子能辨别香臭；耳朵是肾的窍，声音由肺所主，肾的经脉上行至肺，所以使耳朵能听到声音。有人说是用五行长生之法来推演的，木长生于亥，火长生于寅，金长生于巳，水长生于申。心主气味，属火，肺开窍于鼻而内含有己火，所以能感知气味；肺主声音，属金，肾水开窍于耳而内含有申金，所以能听到声音。
第四十一难说：肝脏唯独有两叶，这是与什么相应呢？
回答说：肝属东方木，木对应春季。万物开始生长时，形体尚幼小，心意没有特定的亲附对象，离太阴（肾）还近，离开太阳（心）不远，犹如怀有双重心思，所以有两叶，这也与木叶的形状相应。
肝脏有两叶，对应东方的木。木对应春季，是万物开始生长的初始阶段，草木破壳而出，都是两叶，这是木的本体特征，所以肝脏与之相应。《素问·六节藏象论》说心是阳中的太阳，肾是阴中的太阴，肾水是肝的母亲，心火是肝的儿子，肝是阴中的阳，位于肾之上、心之下，所以说离得太近或太远都不准确。“无亲”，指不专门归属于某一方；“犹有两心”，指或者顺从于阳，或者顺从于阴。
Difficulty 40 states: The classic texts say that the Liver governs colors, the Heart governs odors, the Spleen governs tastes, the Lungs govern sounds, and the Kidneys govern fluids. The nose is the external manifestation of the Lungs, yet it perceives fragrances and foul smells; the ears are the external manifestation of the Kidneys, yet they hear sounds. What is the meaning behind this?
The response is: The Lungs belong to Metal in the West. Metal is born at Si (the fourth Earthly Branch). Si belongs to Fire in the South. Fire corresponds to the Heart, which governs odors; thus, it enables the nose to perceive fragrances and foul smells. The Kidneys belong to Water in the North. Water is born at Shen (the ninth Earthly Branch). Shen belongs to Metal in the West. Metal corresponds to the Lungs, which govern sounds; thus, it enables the ears to hear sounds.
These five governing relationships cannot be verified in the *Suwen* (Basic Questions) or *Lingshu* (Spiritual Pivot); they are excerpts from ancient medical classics. Chen stated: Odors are governed by the Heart. The nose is the orifice of the Lungs. The meridian of the Heart ascends to the Lungs; therefore, it enables the nose to perceive fragrances and foul smells. The ears are the orifices of the Kidneys. Sounds are governed by the Lungs. The meridian of the Kidneys ascends to the Lungs; therefore, it enables the ears to hear sounds. Some argue that this is deduced using the method of the Five Elements' Long Sheng (Long Life/Birth) cycle: Wood is born at Hai, Fire is born at Yin, Metal is born at Si, and Water is born at Shen. The Heart governs odors and belongs to Fire. The Lungs open into the nose and contain Ji Fire within; thus, they can perceive odors. The Lungs govern sounds and belong to Metal. The Kidney Water opens into the ears and contains Shen Metal within; thus, they can hear sounds.
Difficulty 41 states: Why does the Liver alone have two lobes, and what does this correspond to?
The response is: The Liver belongs to Wood in the East. Wood corresponds to Spring. When all things begin to grow, their forms are still young and small, and their intent has no specific attachment. They are close to Taiyin (Kidney/Water) but not far from Taiyang (Heart/Fire). Like having a dual mind, they have two lobes. This also corresponds to the shape of wood leaves.
The Liver has two lobes, corresponding to the Wood of the East. Wood corresponds to Spring, the initial stage when all things begin to grow. When plants and trees split their husks, they emerge with two leaves; this is the original form of Wood, so the Liver corresponds to it. The *Suwen·Liujie Zangxiang Lun* states that the Heart is the Taiyang among Yang organs, and the Kidney is the Taiyin among Yin organs. Kidney Water is the mother of the Liver, and Heart Fire is the child of the Liver. The Liver is Yang within Yin, located above the Kidney and below the Heart; hence, it is said to be neither too close nor too far. "No specific attachment" means not exclusively belonging to one side. "Having a dual mind" implies that it may follow either Yang or Yin.