经曰。观天之道。执天之行。尽矣。盖天一而地二。北辨而南交。入精神之运以行矣。拟之于象。则水火
也。画之于卦。则坎离也。两者相须。弥满六合。物物得之。况于人乎。盖精神生于道者也。是以上古真人。
把握万象。仰观日月。呼吸元气。运气流精。脱骨换形。执天机而行六气。分地纪而运五行。食乳饮血。省约
俭育。日夜流光。独立守神。肌肉若一。故能寿敝天地。无有终时。此其道生之要也。夫道者能却老而全角。
身安而无疾。夫水火用法象也。坎离言交变也。万亿之书。故以水为命。以火为性。土为人。人为主性命者也。
是以主性命者在乎人。去性命者亦在乎人。养性命者亦在乎人。何则。修短寿夭。皆自人为。故经曰。精神内
守。病安从来。又曰。务快其心。逆于生乐。所以然者。性命在乎人。故人受天地之气。以化生性命也。是知
形者生之舍也。气者生之元也。神者生之制也。形以气充。气耗形病。神根据气位。气纳神存。修真之士。法于
阴阳。和于术数。持满御神。专气抱一。以神为车。以气为马。神气相合。可以长生。故曰。精有主。气有元。
呼吸元气。合于自然。此之谓也。智者明乎此理。吹嘘呼吸。吐故纳新。熊经鸟伸。导引按跷。所以调其气也。
平气定息。握固凝想。神宫内视。五脏昭彻。所以守其气也。法则天地。顺理阴阳。交媾坎离。济用水火。所
以交其气也。神水华池。含虚鼓漱。通行荣卫。入于元官。溉五脏也。服气于朝。闭息于暮。阳不欲迭。阴不
欲复。炼阴阳也。以至起居适早晏。出处协时令。忍怒以全阴。抑喜以全阳。泥丸欲多掷。天鼓欲常鸣。形欲
常鉴。津欲常咽。体欲常运。食欲常少。眼者身之
鉴也。常居欲频修。耳者体之牖也。城廓欲频治，面者神之庭也。神不欲复。发者脑之华也。脑不欲减。体者
精之元也。精不欲竭。明者身之宝也。明不欲耗。补泻六腑。淘炼五精。可以固形。可以全生。此皆修真之要
也。故修真之要者。水火欲其相济。土金欲其相养。是以全生之术。形气贵乎安。安则有伦而不乱。精神贵乎
保。保则有要而不耗。故保而养之。初不离于形气精神。及其至也。可以通神明之出。神明之出。皆在于心。
独不观心为君主之官。得所养。则血脉之气。王而不衰。生之本无得而摇也。神之变无得而测也。肾为作强
之官。得所养。则骨髓之气。荣而不枯。蛰封藏之本。无得而倾也。精之处无得而夺也。夫一身之间。心居而
守正。肾下而立始。精神之居。此宫不可太劳。亦不可竭。故精太劳则竭。其属在肾。可以专啬之也。神太用则
劳。其藏在心。静以养之。唯精专然后可以内守。故昧者不知于此。欲拂自然之理。谬为求补之术。是以伪胜
真。以人助天。其可得乎。
《黄帝内经》说：观察天道的规律，执守天行的法则，就足够了。大概天数为一，地数为二，北方与南方分别辨别并交汇，进入精神的运行之中从而得以施行。比拟于物象，就是水和火；画之于卦象，就是坎卦和离卦。两者相互依存，充满天地四方（六合），万物都从中获得滋养，何况是人呢？大概精神是由“道”所化生的。所以上古的真人，把握万象的变化，仰观日月的运行，呼吸元气，使运气流动、精气充盈，甚至能脱去旧骨、更换形体，执掌天机而运行六气，划分地纪而运转五行。他们食用乳汁、饮用血液，生活节俭简约以蓄养生命，日夜流光溢彩，独立坚守精神，肌肉浑然一体。因此能够寿命与天地同久，没有终结之时。这就是“道生”的要旨。所谓“道”，能够使人祛除衰老而保全青春，身体安宁而没有疾病。水火是用来取法象征的，坎离讲的是交感变化。万卷书籍中，所以把水视为命根，把火视为本性，土视为人。人是主宰性命的人。因此，主宰性命的在于人，损害性命的也在于人，保养性命的也在于人。为什么呢？寿命的长短、生命的夭折，都是人为造成的。所以《内经》说：精神如果内守，病邪从哪里来呢？又说：一味追求心意的快乐，违背了生命的乐趣。之所以这样，是因为性命掌握在人自己手中。所以人承受天地的清气，从而化生出性命。由此可知，形体是生命的居所，气是生命的本源，神是生命的主宰。形体依靠气来充实，气耗损则形体生病，神依据气的位置而存在，气纳入则神留存。修真之士，效法阴阳，调和术数，保持精力充沛以驾驭精神，专一其气，抱持合一。以神为车驾，以气为马匹，神气相合，就可以长生。所以说：精有主宰，气有本源。呼吸元气，合乎自然，说的就是这个道理。聪明的人明白这个道理，通过吹嘘呼吸，吐出故气，吸纳新气；像熊一样悬挂伸展，像鸟一样伸颈舒展，运用导引和按跷的方法，以此来调畅他们的气机。平定气息，稳固握拳，凝聚意念，神气内守并内视，五脏清晰明朗，以此来守护他们的气机。效法天地，顺应阴阳之理，使坎离交媾，济助水火，以此来交融他们的气机。吞咽口中的津液（神水华池），含漱空虚，通行营卫之气，进入元宫，灌溉五脏。早晨服食清气，傍晚闭息，阳气不希望重叠，阴气不希望反复，以此来炼化阴阳。以至于起居适应早晚，行动符合时令，克制愤怒以保全阴气，抑制喜悦以保全阳气。泥丸宫（脑部）希望多活动，天鼓（耳部）希望常鸣响，形体希望经常照镜自省，津液希望经常吞咽，身体希望经常运动，饮食希望经常减少。眼睛是身体的镜子，经常居住的地方希望频繁修整；耳朵是身体的窗户，城墙（指头部或面部轮廓）希望频繁治理；面庞是神灵的大厅，神灵不希望反复外露；头发是脑部的荣华，脑部不希望减损；身体是精气的本源，精气不希望枯竭；目光是身体的宝贝，目光不希望耗散。补泻六腑，淘炼五精，可以巩固形体，可以保全生命。这些都是修真的要旨。所以修真的要旨在于：水火希望它们相互济助，土金希望它们相互滋养。因此保全生命的技艺在于：形和气贵在安宁，安宁就有条理而不混乱；精神和贵在保藏，保藏就有要领而不耗散。所以保养它们，起初离不开形、气、神、精。等到达到极致时，就可以通晓神明的出入。神明的出入，都在于心。难道没看过心作为君主之官吗？得到滋养，那么血脉之气就会旺盛而不衰败，生命的根本就不会被动摇。神的变化就不会被测度。肾作为作强之官，得到滋养，那么骨髓之气就会繁荣而不枯槁，蛰伏封藏的根本就不会被倾覆，精的处所就不会被剥夺。在全身之中，心居上而守正，肾在下而立始。精神和精气的居所，这个宫殿不可以太劳累，也不可以枯竭。所以精如果太劳累就会枯竭，它归属于肾，可以专门加以爱惜节制。神如果太使用就会劳损，它藏于心，用静的方法来修养它。只有精专然后才可以内守。所以愚昧的人不知道这一点，想要违背自然的道理，荒谬地追求进补的技术。因此虚假战胜了真实，用人力去辅助天道，这怎么可能做到呢？
The *Classic* states: Observe the Way of Heaven, and hold fast to its operations; this is sufficient. The number of Heaven is one, and the number of Earth is two; North and South are distinguished and intersected, entering the movement of spirit and essence to be executed. Compared to images, they are Water and Fire; drawn as trigrams, they are Kan (Water) and Li (Fire). These two depend on each other, filling the Six Directions (the entire universe), and every thing derives from them, let alone humans. Spirit and essence are born from the Dao. Therefore, the True Persons of antiquity grasped the myriad phenomena, looked up at the sun and moon, breathed in primordial Qi, circulated Qi and flowed with essence, shed old bones and changed forms, held the secrets of Heaven while moving the Six Qi, divided the registers of Earth while operating the Five Phases. They consumed milk and drank blood, practiced frugality and restraint in nurturing life, their radiance flowing day and night, standing alone and guarding their spirit, with muscles becoming one. Thus, they could live as long as Heaven and Earth, having no end. This is the essential point of "Dao generating life." The Dao can eliminate aging and preserve youth, keeping the body safe and free from disease. Water and Fire are used for symbolic representation; Kan and Li speak of interaction and transformation. In tens of thousands of books, Water is regarded as the root of Life (Ming), Fire as Nature (Xing), and Earth as Human. Humans are those who master Life and Nature. Therefore, mastering Life and Nature depends on humans; losing Life and Nature also depends on humans; nourishing Life and Nature also depends on humans. Why? Because longevity or shortness of life, whether one lives long or dies young, is all determined by human action. Thus, the *Classic* says: If spirit and essence are kept within, how can disease arise? It also says: Seeking only to please the mind goes against the joy of life. The reason for this is that Life and Nature depend on humans. Therefore, humans receive the Qi of Heaven and Earth to transform into Life and Nature. From this, we know that Form is the residence of Life, Qi is the origin of Life, and Spirit is the controller of Life. Form is filled by Qi; when Qi is depleted, Form becomes diseased. Spirit resides according to Qi; when Qi is gathered, Spirit remains. Those who cultivate the Dao follow Yin and Yang, harmonize with techniques and numbers, maintain fullness to control Spirit, concentrate Qi and embrace Unity. Taking Spirit as the chariot and Qi as the horses, when Spirit and Qi combine, one can achieve longevity. Thus it is said: Essence has a master, Qi has an origin. Breathing in primordial Qi and conforming to Nature—this is what is meant. Wise people understand this principle: blowing and breathing, expelling the old and absorbing the new; hanging like bears and stretching like birds, using Daoyin (guiding and pulling) and Anqiao (pressing and kneading) to regulate their Qi. Calming the Qi and stabilizing the breath, holding the fist firmly and concentrating thought, keeping Spirit inside and visualizing inwardly, making the five Zang organs clear and bright—to guard their Qi. Following the patterns of Heaven and Earth, complying with the principles of Yin and Yang, causing Kan and Li to interact, assisting Water and Fire—to merge their Qi. Swallowing the divine water in the floral pool, rinsing with emptiness, circulating Ying and Wei (Nutritive and Defensive Qi), entering the Yuan Palace, irrigating the five Zang organs. Absorbing Qi in the morning, closing the breath in the evening; Yang should not overlap, Yin should not repeat—to refine Yin and Yang. Even so, daily activities should suit early and late times, going out and staying in should accord with seasonal orders, restraining anger to preserve Yin, suppressing joy to preserve Yang. The Niwan Palace (brain) should be active often, the Heavenly Drum (ears) should ring often, the form should frequently inspect itself, saliva should be swallowed often, the body should move often, food intake should be reduced often. Eyes are the mirror of the body; places of residence should be cleaned frequently. Ears are the windows of the body; city walls (head/face contours) should be tended to frequently. The face is the court of Spirit; Spirit should not be revealed repeatedly. Hair is the glory of the brain; the brain should not diminish. The body is the origin of Essence; Essence should not be exhausted. Clarity/Vision is the treasure of the body; Vision should not be wasted. Tonifying and reducing the six Fu organs, refining the five essences, can consolidate the form and preserve life. These are all the essentials of cultivation. Therefore, the essentials of cultivation are: Water and Fire should assist each other; Earth and Metal should nourish each other. Thus, the art of preserving life emphasizes that Form and Qi must be peaceful; if peaceful, there is order without chaos. Spirit and Essence must be preserved; if preserved, there is focus without depletion. Therefore, to preserve and nourish them, one does not initially depart from Form, Qi, Spirit, and Essence. When reaching the ultimate stage, one can perceive the emergence of Spirit and Ming (Divine Light). The emergence of Spirit and Ming lies in the Heart. Have you not observed that the Heart is the Official of the Monarch? When nourished, the Qi of blood vessels prospers and does not decline, the root of life cannot be shaken, and the changes of Spirit cannot be measured. The Kidney is the Official of Strength and Ingenuity; when nourished, the Qi of bone marrow flourishes and does not wither, the root of hibernation and storage cannot be overturned, and the place of Essence cannot be deprived. Within the whole body, the Heart resides above and guards righteousness, while the Kidney stands below and establishes beginnings. The dwelling of Spirit and Essence, this palace must not be overworked, nor exhausted. Therefore, if Essence is overworked, it will be depleted; its affiliation is with the Kidney, which can be specifically cherished and restrained. If Spirit is overused, it will become fatigued; it is stored in the Heart, and should be nourished through stillness. Only through concentration can one keep it within. Thus, the ignorant do not understand this; they wish to defy the principles of Nature and absurdly seek methods of supplementation. Therefore, falsehood triumphs over truth, and human effort attempts to assist Heaven. How can this be achieved?