肝血温升，升而不已，温化为热，则生心火。肺气清降，降而不已，清化为寒，则生肾水。
水之寒者，六腑之悉凝也。阴极则阳生，故纯阴之中，又含阳气。火之热者，六腑之尽发也，
阳极则阴生，故纯阳之中，又胎阴气，阴中有阳，则水温而精盈。阳中有阴，则气清而神旺。神发于心
，方其在肝，神未旺也，而已现其阳魂。精藏于肾，方其在肺，精未盈也，而先结其阴魄。素问∶随
神往来者，谓之魂。并精出入者，谓之魄。盖阳气方升，未能化神，先化其魂。阳气全升，则魂变而为神
。魂者神之初气，故随神往来。阴气方降，未能生精，先生其魄。阴气全降，
则魄变而为精，魄者，精之始基，故并精而出入也。
肝主筋，其荣爪。心主脉，其荣色。脾主肉，其荣唇。肺主皮，其荣毛。肾主骨，其荣发。
凡人之身，骨以立其体干，筋以束其关节，脉以通其荣卫，肉以培其部分，皮以固其肌肤。皮
毛者，肺金之所生也。肺气盛，则皮毛致密而润泽。肌肉者，脾土之所生也。脾气盛，则肌肉丰满而充
实。脉络者，心火之所生也。心气盛，则脉络疏通而条达。筋膜者，肝木之所生也。肝气盛，则筋膜滋荣
而和畅。髓骨者，肾水之所生也。肾气盛，则髓骨坚凝而轻利。五气皆备，形成而体具矣。
Liver blood warms and ascends; if the ascent continues without cessation, the warmth transforms into heat, thereby generating Heart Fire. Lung Qi clears and descends; if the descent continues without cessation, the clarity transforms into cold, thereby generating Kidney Water.
The coldness of Water stems from the comprehensive condensation of the Six Fu Organs. When Yin reaches its extreme, Yang is born; thus, within pure Yin, Yang Qi is contained. The heat of Fire stems from the comprehensive emission of the Six Fu Organs;
when Yang reaches its extreme, Yin is generated; thus, within pure Yang, Yin Qi is conceived. With Yang within Yin, Water becomes warm and Essence (Jing) becomes abundant. With Yin within Yang, Qi becomes clear and Spirit (Shen) becomes vigorous. Spirit originates in the Heart;
while it resides in the Liver, Spirit has not yet become vigorous, but its Yang aspect, Hun (Ethereal Soul), already manifests. Essence is stored in the Kidneys; while it resides in the Lungs, Essence has not yet become abundant, but its Yin aspect, Po (Corporeal Soul), first coagulates. The *Suwen* states: "That which accompanies Spirit to come and go is called Hun." "That which enters and exits with Essence is called Po." Generally, when Yang Qi begins to ascend, it is insufficient to transform into Spirit, so it first transforms into Hun. When Yang Qi fully ascends, Hun changes into Spirit.
Hun is the initial Qi of Spirit, therefore it accompanies Spirit in its comings and goings. When Yin Qi begins to descend, it is insufficient to generate Essence, so it first generates Po. When Yin Qi fully descends,
Po changes into Essence. Po is the foundational basis of Essence, therefore it enters and exits with Essence.
The Liver governs the sinews (tendons), and its flourishing manifests in the nails. The Heart governs the vessels, and its flourishing manifests in the complexion. The Spleen governs the muscles, and its flourishing manifests in the lips. The Lungs govern the skin, and its flourishing manifests in the body hair. The Kidneys govern the bones, and their flourishing manifests in the hair.
In the human body, bones establish the structural framework, sinews bind the joints, vessels facilitate the circulation of Ying (Nutritive) and Wei (Defensive) Qi, muscles nourish the bodily parts, and skin secures the flesh and integument. Skin and hair are produced by Lung Metal. When Lung Qi is robust, skin and hair are dense and lustrous. Muscles are produced by Spleen Earth. When Spleen Qi is robust, muscles are plump and substantial. Vessels are produced by Heart Fire. When Heart Qi is robust, vessels are unobstructed and smooth. Sinews are produced by Liver Wood. When Liver Qi is robust, sinews are nourished and harmonious. Marrow and bones are produced by Kidney Water. When Kidney Qi is robust, marrow and bones are firm and agile. When the Qi of the Five Zang Organs is complete, form takes shape and the physical body is established.