夫人之有是身也。资始于天。资生于地。禀精气以成形。藉阴阳而赋命。顾天地有五方之殊。斯气化有五
行之异。风土于焉而变。气色由是而分矣。经曰。东方之人多青。南方之人多赤。西方之人多白。北方之人
多黑。中央之人多黄。此相应之谓也。然相应者色之常。不相应者色之变。或常或变。而无过不及者。平色
也。或常或变。而有过不及者。病色也。要之天包地外。地在天中。天气胜地气为顺。地气胜天气为逆。五色
之见。或不合乎五方之正色。而合乎四时之平色者。常也。承天而时行地道也。不合乎四时。而与声音脉
症相生者。病之顺者也。不合乎四时。而与声音脉症相克者。病之逆者也。五色之变。可比例而参观也。析
而言之。一方之间。一邑之内。地形有高下。则风气有寒温。地形有燥湿。则风气有刚柔。风气既感于中。形
色必应于外。是故坚土之人刚。弱土之人柔。垆土之人大。沙土之人细。息土之人美。HT 土之人丑。山林之
民毛而方。得木气多也。川泽之民黑而津。得水气多也。丘陵之民专而长。得火气多也。坟衍之民皙而瘠。
得金气多也。原隰之民。丰肉而痹。得土气多也。望其容貌。瞻其颜色。近者小异。远者大异。皆可以风气之
寒温。而知其色脉之常变焉。以色脉之生克。而知其病症之顺逆焉。凡四海之大。十室之小。苟有诸中。必
形诸外。准其情。察其理。相其势。度其时。引而伸之。触类而长之。风土虽变。气色虽异。岂能外乎五行哉。散
之在理。则有万殊。统之在道。则无二致矣。
人的身体，起始于天（禀受先天之精），生长于地（摄取后天水谷）。凭借天地精气而构成形体，依托阴阳二气而赋予生命。然而，天地有东、南、西、北、中五个方位的差异，因此气化也有金、木、水、火、土五行的不同。风土气候由此发生变化，面色气色也因此有所区分。《内经》说：东方的人多青色，南方的人多赤色，西方的人多白色，北方的人多黑色，中央的人多黄色。这就是相应的道理。然而，相应是面色的常态，不相应则是面色的变态。无论是常态还是变态，只要没有太过或不及的，就是平人正常的颜色（平色）。无论是常态还是变态，如果出现过度的表现，就是病态的颜色（病色）。总之，天包裹在地之外，地处于天之中。天气胜过地气为顺，地气胜过天气为逆。五色显现，如果不合乎五方对应的正色，但合乎四时变化的平色，这是常态，因为这是顺应天道而依循地道运行的结果。如果不合乎四时变化，但与声音、脉象、症状相生，这是病情顺遂的表现；如果不合乎四时变化，而与声音、脉象、症状相克，这是病情逆乱的表现。五色的变化，可以类推并参照观察。
进一步分析而言，在一个地区、一个县邑之内，地形有高下之分，风气就有寒温之别；地形有燥湿之分，风气就有刚柔之异。风气既然感应于体内，形体气色必然反映于外表。所以，生活在坚实土壤地区的人性格刚强，生活在松软土壤地区的人性格柔和；住在黑垆土地区的人体型高大，住在沙土地区的人体型细小；住在肥沃息土地区的人容貌美丽，住在贫瘠HT土地区的人容貌丑陋。居住在山林地区的民众毛发浓密且面部方正，这是因为得木气较多；居住在川泽地区的民众肤色黑且润泽，这是因为得水气较多；居住在丘陵地区的民众性格专一且身材修长，这是因为得火气较多；居住在坟衍（高平之地）地区的民众皮肤白皙且消瘦，这是因为得金气较多；居住在原隰（低湿之地）地区的民众肌肉丰满但易患痹症，这是因为得土气较多。观察他们的容貌，审视他们的颜色，相近的地方差异小，遥远的地方差异大。这些都可以通过风气的寒温，来推断其色脉的常与变；通过色脉的生克关系，来推断病症的顺与逆。凡是四海之大，或是十室之小的地方，只要内部有病邪，必定会反映在外部。审察其情状，推究其原理，观察其态势，揣度其时机，引申开来，触类旁通。即使风土变化、气色各异，难道能超出五行规律之外吗？分散来看，道理有万般殊异；统摄来看，大道则没有二致。
The human body originates from Heaven (receiving prenatal essence) and is nourished by Earth (absorbing postnatal grain and water). It takes shape through the essence of Heaven and Earth, and is endowed with life via Yin and Yang. However, Heaven and Earth differ in their five directions (East, South, West, North, Center), thus Qi transformation varies according to the Five Elements (Wood, Fire, Earth, Metal, Water). Consequently, local climate and soil conditions change, leading to distinctions in complexion and Qi color. The Classics state: People in the East tend to have a bluish-green complexion; people in the South tend to have a red complexion; people in the West tend to have a white complexion; people in the North tend to have a black complexion; people in the Center tend to have a yellow complexion. This is referred to as correspondence. Correspondence represents the normal state of complexion, while non-correspondence represents the abnormal state. Whether normal or abnormal, if there is no excess or deficiency, it is considered a "Ping Se" (Normal Complexion). If there is excess or deficiency, it is considered a "Bing Se" (Disease Complexion). In summary, Heaven envelops Earth, and Earth lies within Heaven. When Heavenly Qi overcomes Earthly Qi, it is favorable (Shun); when Earthly Qi overcomes Heavenly Qi, it is unfavorable (Ni). Regarding the manifestation of the Five Colors: if they do not conform to the standard colors of the five directions but align with the normal colors of the four seasons, this is considered normal, as it follows Heaven's timing and Earth's principles. If they do not conform to the four seasons but are mutually generating (Xiang Sheng) with voice, pulse, and symptoms, this indicates a favorable progression of disease. If they do not conform to the four seasons but are mutually overcoming (Xiang Ke) with voice, pulse, and symptoms, this indicates an unfavorable progression of disease. The variations in the Five Colors can be understood through analogy and observation.
Analyzing further, within a single region or county, terrain elevation differences lead to variations in wind and Qi (cold vs. warm); terrain moisture differences lead to variations in wind nature (rigid vs. soft). Once the local wind and Qi affect the interior, the physical appearance and complexion must reflect externally on the surface. Therefore, people living in firm soil areas tend to have rigid constitutions; those in weak/loose soil areas tend to have soft constitutions. Those in Lu soil (dark clay) areas tend to be large-statured; those in sandy soil areas tend to be slender. Those in Xi soil (fertile land) areas tend to have beautiful features; those in HT soil (barren land) areas tend to have plain features. People dwelling in mountainous and forested regions often have coarse hair and square faces, due to excessive Wood Qi. People dwelling in riverine and marshy regions often have dark and moist complexions, due to excessive Water Qi. People dwelling in hilly regions often have focused temperaments and tall statures, due to excessive Fire Qi. People dwelling in high flatlands (Fen Yan) often have fair and emaciated appearances, due to excessive Metal Qi. People dwelling in low-lying wetlands (Yuan Xi) often have plump flesh but are prone to Bi syndrome (obstruction syndrome), due to excessive Earth Qi. By observing their appearance and examining their complexion, minor differences appear in nearby areas, while major differences appear in distant areas. All these can be used to deduce the normality or variability of complexion and pulse based on the coldness or warmth of the local wind and Qi, and to determine the favorability or unfavorability of diseases based on the generating and overcoming relationships of complexion and pulse. Wherever there is a population, whether vast like the Four Seas or small like ten households, internal pathology will inevitably manifest externally. By assessing circumstances, investigating principles, observing trends, and estimating timing, one can extend knowledge and apply it analogously. Although local climates vary and complexions differ, can they possibly lie outside the laws of the Five Elements? Dispersed in principle, there are myriad differences; unified in the Dao, there is no divergence.