阴阳应象论云诸脉者皆属于目目得血而能视五脏六腑精气皆上注于目而为之精精之窠为
眼骨之
精为瞳子筋之精为黑眼血之精为络其窠气之精为白眼肌肉之精则为约束里撷筋骨血气之精而
与脉并为系上属于脑后出于项中故邪中于项因逢其身之虚其入深则即随眼系入于脑则脑转脑
转则引目系急目系急则目眩以转矣邪中其精其精所中不相比也则精散精散则视岐故见两物目
者五脏六腑之精荣卫魂魄之所常营也神气之所主也故神劳则魂魄散志意乱是故瞳子黑眼发于
阴白眼赤脉发于阳故阴阳合传而为精明也目者心之使也心者神之舍也故神精乱而不转卒然见
非
常之处精神魂魄散不相得故曰惑也夫十二经脉三百六十五络其血气皆上走于面而走空窍其清
阳气上散于目而为精其气走于耳而为听因心事烦冗饮食失节劳役过度致脾胃虚弱心火大盛则
百脉沸腾血脉逆行邪害空窍天明则日月不明矣夫五脏六腑之精气皆禀受于脾上贯于目脾者诸
阴之首也目者血脉之宗也故脾虚则五脏之精气皆失所司不能归明于目矣心者君火也主人之神
宜静而安相火化行其令相火者包络也主百脉皆荣于目既劳役运动势乃妄行又因邪气所并而损
血脉故诸病生焉凡医者不理脾胃及养血安神治标不治本是不明正理也
凡心包络之脉出于心中以代心君之行事也与少阳为表里瞳子散大者少阴心之脉挟目系厥
阴肝之
脉连目系心主火肝主木此木火之势盛也其味则宜苦宜酸宜凉大忌辛辣热物以助木火之邪也饮
食中常知此理可也夫辛主散热则助火故不可食诸酸主收心气泻木火也诸苦泻火热则益水也尤
忌食冷水大寒之物此则能损胃气不行则元气不生元气不生胃气下流胸中三焦之火及心火乘于
肺
上入脑灼髓火主散溢瞳子开大大热之物又助火邪此盖不可食验也药中云茺蔚子一味辛及主益
睛辛者是助火也故去之乃加黄芩黄连泻中焦之火芩能泻上焦肺中之火以酒洗之乃寒因热用也
又去青葙子为助阳火也加五味子以收瞳人间大且火之与气势不两立故内经曰壮火食气气食少
火少火生气壮火散气诸酸之物能助元气孙真人云五月常服五味助五脏气以补西方肺金法云以
酸
补之以辛泻之辛泻气则明矣或曰药中有当归其味亦辛而甘其不去者何此辛甘一味以其
和血之圣药况有甘味又欲以为向导为诸药之使耳
《阴阳应象大论》中说：“所有的经脉都联系于目。”眼睛得到血液的滋养才能看见事物。五脏六腑的精气都向上灌注到眼睛，从而形成眼的视觉功能。精气汇聚之处称为眼，骨骼的精气表现为瞳子，筋的气血精气表现为黑眼（虹膜），血液的精气表现为络脉（眼内血管），气的精气表现为白眼（巩膜），肌肉的精气则表现为眼睑（约束）。这些来自筋骨、气血的精气与经脉结合，形成目系，向上连接脑后，出于项中。因此，邪气侵袭项部，如果恰逢人体正气虚弱，邪气就会深入，随着目系进入脑部。邪入脑则导致头晕，头晕会牵引目系紧张，目系紧张就会导致眩晕和视物旋转。
邪气侵入眼的精气，如果所侵部位不相协调，就会导致精气散乱，精气散乱就会出现复视，所以看到两个物体。眼睛是五脏六腑精气的汇聚处，也是营卫、魂魄经常营守的地方，更是神气所主宰的部位。因此，精神过度劳累会导致魂魄散乱、意志混乱。所以，瞳子和黑眼发源于阴，白眼和赤脉发源于阳，阴阳和谐交融才能形成明亮的视力。眼睛是心的使者，心是神的居所。如果精神紊乱不能正常运作，突然看到不寻常的景象，导致精神、魂魄分散而不相协调，这就叫做“惑”（迷惑、幻觉）。
十二经脉和三百六十五络穴，其气血都上行于面部并通达各个孔窍。清阳之气上行散布于目而形成视觉，浊气下行走于耳而形成听觉。如果因为心事烦冗、饮食失节、劳役过度，导致脾胃虚弱、心火亢盛，那么百脉沸腾，血脉逆行，邪气侵害空窍，就像天明的日月失去光明一样。五脏六腑的精气都禀受于脾，向上贯通于目。脾是诸阴之首，眼睛是血脉的宗汇。所以脾虚则五脏的精气都失去统摄，不能使目光清明。心是君火，主人的神志应当安静平和；相火行使命令，相火即心包络，主管百脉，都荣养于目。既然劳役运动使得相火妄行，又因邪气侵犯而损伤血脉，各种疾病就产生了。凡是医生不调理脾胃及养血安神，只治标不治本，是不明白正理的表现。
心包络的经脉出于心中，代替心君行事，与少阳胆经互为表里。瞳子散大，是少阴心经的脉气挟持目系所致；厥阴肝经的脉气连接目系。心主火，肝主木，这是木火之势旺盛的表现。在口味上适宜苦味、酸味、凉性食物，大忌辛辣热物，以免助长木火的邪气。饮食中常懂得这个道理就可以了。辛味主散热，但会助火，所以不可食用；酸味主收敛，能泻心气、平抑木火；苦味能泻火热，从而益水。尤其忌讳食用冷水和大寒之物，这会损伤胃气，导致气机不行，元气不生。元气不生，胃气下流，胸中三焦之火及心火就会乘势上逆侵犯肺脏，进而入脑灼烧骨髓。火主散溢，会导致瞳子开大。大热之物又会助长火邪，这些都是不可食用的验证。
药物方面，《药性论》等医书云：茺蔚子一味辛温，主要作用是益睛。但辛味助火，所以要去除它。改为加入黄芩、黄连以泻中焦之火；黄芩能泻上焦肺中之火，用酒洗制，属于“寒因热用”的方法。又去掉青葙子，因为它助阳火。加入五味子以收敛瞳孔。人间的道理是，火与气势不能两立，所以《内经》说：“壮火食气，气食少火；少火生气，壮火散气。”各种酸味的食物能辅助元气。孙思邈说：“五月常服五味子，以助五脏之气。”补法云：“以酸补之，以辛泻之。”辛味泻气，这就能使视力明亮了。有人问：药方中有当归，其味亦辛甘，为什么不除去呢？这是因为辛甘合用是和血的圣药，况且有甘味作为向导，作为诸药的使药。
The *Treatise on the Correspondence of Yin and Yang* states: "All meridians connect to the eyes." The eyes are able to see when they receive nourishment from blood. The essence of the five zang organs and six fu organs all ascend to the eyes, thereby forming visual function. The gathering place of essence is called the eye; the essence of bone manifests as the pupil (pupil); the essence of sinew manifests as the black eye (iris); the essence of blood manifests as the collaterals (intraocular vessels); the essence of qi manifests as the white eye (sclera); and the essence of muscle manifests as the eyelids (constraints). These essences derived from sinews, bones, blood, and qi combine with the meridians to form the optic nerve system (optic pathway), which ascends to connect with the back of the brain and emerges from the nape. Therefore, when pathogenic factors invade the nape, especially if accompanied by a deficiency in the body's healthy qi, the pathogens may penetrate deeply and follow the optic pathway into the brain. Pathogens entering the brain cause dizziness, which pulls on the optic pathway causing tension; tension in the optic pathway leads to vertigo and rotational visual disturbances.
If pathogenic factors invade the essence of the eye, and the invaded sites are not coordinated, the essence will scatter. Scattered essence results in diplopia (seeing double objects). The eyes are the gathering place of the essence of the five zang organs and six fu organs, the site where Ying-Qi (nutritive and defensive qi) and Hun-Po (ethereal and corporeal souls) frequently circulate, and the seat governed by Shen (spirit). Therefore, excessive mental labor causes Hun and Po to scatter and Yi (will/intention) to become chaotic. Thus, the pupils and black eyes originate from Yin, while the white eyes and red vessels originate from Yang; the harmonious interaction of Yin and Yang produces clear vision. The eyes are the messengers of the Heart, and the Heart is the residence of Shen. If Shen and Jing (essence) become disordered and fail to function normally, sudden perception of abnormal phenomena occurs, causing Shen, Jing, Hun, and Po to scatter and lose coordination; this state is called "Huo" (delusion/confusion).
The twelve primary meridians and 365 acupoints have their blood and qi ascending to the face and penetrating all orifices. Clear Yang qi ascends and disperses into the eyes to form vision, while turbid Qi descends to the ears to form hearing. If mental distress, irregular diet, or overwork leads to Spleen-Stomach weakness and excessive Heart Fire, the hundred meridians will boil, blood vessels will flow retrograde, and pathogenic factors will damage the orifices, much like the sun and moon losing brightness at dawn. The essence of the five zang organs and six fu organs is derived from the Spleen and ascends to the eyes. The Spleen is the head of all Yin meridians, and the eyes are the congregation of blood vessels. Therefore, Spleen deficiency causes the essence of the five zang organs to lose control, failing to clarify vision. The Heart is the Ministerial Fire (Jun Huo), governing the spirit, which should remain calm and peaceful. The Assistant Fire (Xiang Huo) executes commands; the Assistant Fire refers to the Pericardium (Pericardium Meridian), which governs the hundred meridians that nourish the eyes. Since physical exertion causes the Assistant Fire to act recklessly, and pathogenic factors further damage the blood vessels, various diseases arise. Physicians who do not regulate the Spleen and Stomach, nourish blood, and calm the spirit, but only treat symptoms without addressing the root, fail to understand the correct principles.
The meridian of the Pericardium originates from the Heart, acting on behalf of the Heart Monarch, and is exterior-interior related to the Shaoyang (Gallbladder) meridian. Dilated pupils indicate that the Shaoyin (Heart) meridian's qi supports the optic pathway; the Jueyin (Liver) meridian connects to the optic pathway. The Heart governs Fire, and the Liver governs Wood; this represents an excess of Wood-Fire energy. Dietary tastes should be bitter, sour, and cool, strictly avoiding pungent and hot foods to prevent aiding the Wood-Fire pathogenic factors. Understanding this principle in daily diet is advisable. Pungent flavors dissipate heat but aid Fire, so they should not be consumed. Sour flavors promote consolidation, drain Heart Qi, and subdue Wood-Fire. Bitter flavors drain Heat-Fire, thereby benefiting Water. Cold water and excessively cold foods are particularly contraindicated, as they damage Stomach Qi, obstruct Qi mechanism, and prevent the generation of Yuan Qi (Primary Qi). If Yuan Qi fails to generate, Stomach Qi sinks, allowing Fire of the Sanjiao (Triple Burner) and Heart Fire to counterflow upward, invading the Lungs, entering the brain, and burning the marrow. Fire promotes dispersion, leading to dilated pupils. Hot foods further aid Fire pathogenic factors; these are verified reasons for dietary restrictions.
Regarding herbal medicine, texts such as *Yao Xing Lun* state: Elsholtzia Fructus (Chongwei Zi) has a pungent nature and primarily benefits the eyes. However, since pungency aids Fire, it is removed. Instead, Scutellariae Radix (Huang Qin) and Coptidis Rhizoma (Huang Lian) are added to drain Middle Jiao Fire; Scutellariae Radix drains Upper Jiao Lung Fire, prepared with wine washing, employing the method of "treating cold with heat" (Han Yin Re Yong). Semen Celosiae (Qingxiang Zi) is removed because it aids Yang Fire. Schisandrae Fructus (Wuweizi) is added to astringe the pupils. In human physiology, Fire and Qi cannot coexist in excess; thus, the *Neijing* states: "Strong Fire consumes Qi, Qi feeds mild Fire; mild Fire generates Qi, strong Fire scatters Qi." Various sour foods assist Yuan Qi. Sun Simiao stated: "In the fifth month, regularly consume Wuweizi to assist the Qi of the five zang organs." The supplementation method states: "Supplement with sour, drain with pungent." Pungency drains Qi, thereby clarifying vision. One might ask: Dang Gui (Angelica Sinensis) in prescriptions also has a pungent and sweet flavor; why is it not removed? Because the combination of pungent and sweet is the supreme remedy for harmonizing blood, and furthermore, the sweet flavor acts as a guide and envoy for the other herbs.