五脏各有天性，遂其性则欲，违其性则苦，本脏所苦为泻，本脏所欲为补。盖指水润下作咸，火炎上作苦，
木曲直作酸，金从革作辛，土稼穑作甘。五味而言，如肝苦急，急食甘以缓之。肝欲散，急食辛以散之，以辛补
之，以酸泻之。心苦缓，急食酸以收之。心欲软，急食咸以软之，以酸补之，以甘泻之。脾苦湿，急食苦以燥之。
脾欲缓，急食甘以缓之，以甘补之，以苦泻之。肺苦气上逆，急食苦以泄之。肺欲收，急食酸以收之，以酸补之，
以辛泻之。肾苦燥，急食辛以润之。肾欲坚，急食苦以坚之，以苦补之，以咸泻之。虽然苦者直行而泄，过苦则
伤气，须咸以佐，辛者横行而散，过辛则伤皮毛，须苦以佐。酸者束而收敛，过酸则伤筋，须辛以佐。咸者止而
软坚，过咸则伤血，须甘以佐。甘之一味，可上可下，土位居中而兼五行也，过甘则伤胃，须酸以佐。淡品无味，
五脏无归，专入太阳，微利小便，过利乃伤，须统五味而消息之。知其数者，其于苦欲补泻益得共平，而心肝脾
肺肾各尽其性矣。
万物皆药也。利而行之，无有窒碍，方书之所以作也。是故阴中阳、阴中阴、阳中阴，阳中阳，品药之性也。
君为
王，臣为辅，佐为助，使为用，制方之旨也。逆则衰，从乃制，经以时，权得中，治病之法也。辛甘味薄为阳，
辛甘则发散，味薄则通，阴中阳也；酸苦味浓为阴，酸苦则收降，味浓则泄，阴中阴也；味咸气薄为阴，味咸则
滋利，气薄则和解，阳中阴也；味淡气浓为阳，味淡则渗泄，气浓则温热，阳中阳也。必热必寒，必固必散，君
之主也；不宣不明，不授不行，臣之辅也；或劫或和，或发或补，佐之助也；能升能降，能合能开，使之用也。
殛暴须夺，破留须行，溃坚须攻，除湿须泄，“逆则衰”也；热病用寒药而导寒攻热者必热，阳明病发热大便硬
者，大承气汤，酒制大黄热服之类也；寒病用热药而导热去寒者必寒，少阴病下利，服附子干姜不止，白通汤加
人尿猪胆汁之类也；塞病用通药而导通除塞者必塞，胸闷烦惊，小便不利，柴胡加龙骨牡蛎汤之类也；通病用塞
药而导塞止通者必通，太阳中风，下利，心下痞硬，十枣汤之类也，“从乃制”也。惊者平之，劳者温之，散者
收之，损者益之，“经以时”也；治远以大，治近以小，治主以缓，治客以急，“权得中”也。易曰∶同声相应，
同气相求，水流湿，火就燥，本乎天者亲上，本乎地者亲下，物各从其类也。为其从类，乃根据类品药，缘药制方，
按方治病，荡荡平平，与物皆春，功其成也。或曰∶药阴则无阳，药阳则无阴，眼药杂沓，无用君臣佐使，眼病
纯一，不必逆从经权，此齐东野人，谓之瞽而惑于大道者也。
Each of the Five Zang Organs has its own innate nature. Following its nature is termed "Desire" (Yu), while violating its nature is termed "Bitterness/Suffering" (Ku). The method used to address the organ's suffering is "Draining/Reducing" (Xie), and the method used to address its desire is "Tonifying/Nourishing" (Bu). This refers to the principles stated in the *Book of Documents*: Water moistens and flows downward, corresponding to the Saline flavor; Fire flares upward, corresponding to the Bitter flavor; Wood bends and straightens, corresponding to the Sour flavor; Metal can be forged and changed, corresponding to the Pungent flavor; Earth sows and reaps, corresponding to the Sweet flavor. Regarding the five flavors: For example, when the Liver suffers from tension/spasms (Liver Ku Ji), one should urgently consume Sweet substances to relax it. When the Liver desires dispersion (Liver Yu San), one should urgently consume Pungent substances to disperse it; using Pungent substances constitutes tonification, while using Sour substances constitutes draining. When the Heart suffers from laxity/flaccidity (Heart Ku Huan), one should urgently consume Sour substances to astringe it. When the Heart desires softening (Heart Yu Ruan), one should urgently consume Saline substances to soften it; using Sour substances constitutes tonification, while using Sweet substances constitutes draining. When the Spleen suffers from dampness (Spleen Ku Shi), one should urgently consume Bitter substances to dry it. When the Spleen desires relaxation (Spleen Yu Huan), one should urgently consume Sweet substances to moderate it; using Sweet substances constitutes tonification, while using Bitter substances constitutes draining. When the Lungs suffer from rebellious Qi ascending (Lung Ku Qi Shang Ni), one should urgently consume Bitter substances to drain/descend it. When the Lungs desire consolidation/astringency (Lung Yu Shou), one should urgently consume Sour substances to astringe them; using Sour substances constitutes tonification, while using Pungent substances constitutes draining. When the Kidneys suffer from dryness (Kidney Ku Zao), one should urgently consume Pungent substances to moisten them. When the Kidneys desire firmness (Kidney Yu Jian), one should urgently consume Bitter substances to firm them; using Bitter substances constitutes tonification, while using Saline substances constitutes draining. Although Bitter substances move directly and drain, excessive use damages Qi, requiring Saline substances as assistants. Pungent substances move horizontally and disperse, but excessive use damages the skin and hair, requiring Bitter substances as assistants. Sour substances bind and astringe, but excessive use damages the sinews, requiring Pungent substances as assistants. Saline substances stop and soften hardness, but excessive use damages Blood, requiring Sweet substances as assistants. The Sweet flavor alone can move up or down; since Earth resides in the center and encompasses the Five Elements, excessive use damages the Stomach, requiring Sour substances as assistants. The Dan (Light/Bland) flavor has no taste, does not belong to any of the Five Zang, enters exclusively into the Taiyang channel, slightly promotes urination, but excessive promotion causes damage; therefore, one must weigh and adjust among all five flavors. Those who understand these numbers will achieve greater balance in applying the methods of addressing suffering and desire through tonification and draining, allowing the Heart, Liver, Spleen, Lungs, and Kidneys to fully exert their natures.
All things can serve as medicines. Utilizing their properties to regulate the body encounters no obstruction; this is why medical formularies were created. Thus, Yin containing Yang, Yin containing Yin, Yang containing Yin, and Yang containing Yang constitute the classification of medicinal properties. The Sovereign (Jun) drug acts as the King, the Minister (Chen) drug acts as the assistant, the Assistant (Zuo) drug provides support, and the Guide (Shi) drug directs usage; this is the principle of formulating prescriptions. Treating contrary to the disease pattern leads to decline; treating in accordance with the pattern achieves control; adhering to classics and timing constitutes standard practice; exercising discretion to find the middle ground constitutes therapeutic method. Pungent and Sweet flavors that are thin/light in qi belong to Yang; Pungent and Sweet disperse, and thin qi unblocks, constituting "Yang within Yin." Sour and Bitter flavors that are thick/heavy in qi belong to Yin; Sour and Bitter collect and descend, and thick qi drains, constituting "Yin within Yin." Saline flavors that are thin/light in qi belong to Yin; Saline nourishes and lubricates, and thin qi harmonizes, constituting "Yin within Yang." Dan (Bland) flavors that are thick/heavy in qi belong to Yang; Dan permeates and drains, and thick qi warms, constituting "Yang within Yang." Being necessarily hot or cold, necessarily astringent or dispersing, is the role of the Sovereign drug; without dissemination there is no clarity, without administration there is no action, which is the assistance of the Minister drug; whether劫 (seizing/attacking) or harmonizing, whether dispersing or tonifying, is the support of the Assistant drug; being able to ascend or descend, combine or open, is the function of the Guide drug. Violent pathogens must be forcibly removed; stasis must be moved; hardness must be attacked; dampness must be drained—this is "treating contrary leads to decline." In heat diseases using cold drugs, guiding cold to attack heat inevitably results in heat retention; for example, in Yangming disease with fever and hard stool, Da Cheng Qi Tang (Major Order the Qi Decoction) or wine-processed Rhubarb taken hot are used. In cold diseases using hot drugs, guiding heat to remove cold inevitably results in cold retention; for example, in Shaoyin disease with diarrhea, if Aconite and Dried Ginger fail to stop it, Bai Tong Tang (White Pass Decoction) with human urine and pig bile is added. In obstructive diseases using unblocking drugs, guiding unblocking to remove obstruction inevitably results in continued obstruction; for example, in cases of chest fullness, irritability, fright, and difficult urination, Chai Hu Jia Long Gu Mu Li Tang (Bupleurum Plus Dragon Bone and Oyster Shell Decoction) is used. In unobstructed/diarrheal diseases using astringent drugs, guiding astringency to stop flow inevitably results in blockage; for example, in Taiyang wind-strike with diarrhea and epigastric hardness, Shi Zao Tang (Ten Jujube Decoction) is used—this is "treating in accordance achieves control." Fright is treated by calming; exhaustion is treated by warming; dispersion is treated by collecting; deficiency is treated by supplementing—this is "standard practice according to timing." Treating distant/chronic conditions requires large formulas; treating recent/acute conditions requires small formulas; treating primary conditions requires slow/gentle remedies; treating secondary/external conditions requires urgent/rapid remedies—this is "exercising discretion to find the middle ground." The *I Ching* states: Sounds resonate with each other; similar energies seek each other; water flows to wetness; fire moves toward dryness. That which originates from Heaven tends upward; that which originates from Earth tends downward. All things follow their kind. Because they follow their kind, one selects medicines based on category, forms prescriptions based on medicines, and treats diseases based on prescriptions. This approach is vast, level, and harmonious, bringing the vitality of spring to all things, thereby completing the work. Some say: Medicines are either Yin or Yang; if a medicine is purely Yin, it lacks Yang; if purely Yang, it lacks Yin. Eye medications are mixed and chaotic, requiring no Sovereign, Minister, Assistant, or Guide roles. Eye diseases are uniform/pure, so there is no need to discuss contrary/accommodating treatments or standard/discretionary methods. Such views are akin to tales told by villagers east of Qi, describing blind people confused by the Great Dao.