《原病式》曰∶目昧不明，目赤肿痛，翳膜 疡，皆为热也。及目膜，俗谓之眼黑，亦
为热也。或平白目无所见者，热气郁之甚也。或言目昧为肝肾虚冷者，误也。是以妄谓肝生
于目，肾主瞳子，故妄言目昧为虚而冷也。然肾水，冬阴也，虚则当热；肝木，春阳也，虚
则当冷。肾阴肝阳，岂能同虚而为冷者欤。或通言肝肾之中，阴实阳虚，而无由目昧也。俗
妄谓肝肾之气衰少，而不能至于目也。不知经言热甚目瞑，眼黑也，岂由寒尔。又考仲景言
伤寒病，热极则不识人，乃目盲也。《正理论》曰∶由热甚怫郁于目而致之然也。若目无所
见，耳无所闻，悉由热气怫郁、玄府闭密而致。气液血脉，荣卫精神，不能升降出入故也，
各随郁结微甚而见病之轻重也。故知热郁于目，无所见也。故目微昏者，至近则转难辨物，
由目之玄府闭小也，隔缣视物之象也。或视如蝇翼者，玄府有所闭合者也。或目昏而见黑花
者，由热气甚而发之于目。亢则害，承乃制，而反出其泣，气液昧之，以其至近，故虽微而
亦见如黑花也。及冲风泣而目暗者，由热甚而水化制之也。故经言厥则目无所见。夫人厥则
阳气并于上，阴气并于下。阳并于上，则火独光也；阴气并于下则足阴，足阴则胀也。夫一
水不能胜五火，故目 而盲。是以冲风泣下而不止。夫风之中于目也，阳气内守于睛，是火
气燔目，故见风泣下。
按∶此论热甚怫郁，阴阳并厥，玄府闭密，致目病之由为详，盖一主于火热之化也。若
由饮食辛热，七情所动，六气淫郁，气血虚实，则东垣、子和、陈无择辈，论亦已详，然亦
有痰热湿热，与夫服食金石燥热之药致者。或久病后，荣卫虚弱，肝气肾阴不足，或元气精
气虚衰，及脱营为病，皆有虚热实热之殊，并宜分治。
《原病式》中说：视物模糊不清，眼睛红肿疼痛，眼睑生疮疡，都是由于热邪所致。以及眼睑下垂（俗称“眼黑”），也是由热邪引起。有的人平素视力正常却突然看不见东西，这是因为热邪郁结非常严重。有人说视物模糊是肝肾虚冷造成的，这是错误的。他们胡乱认为肝开窍于目，肾主宰瞳孔，所以妄称视物模糊是由于虚寒所致。然而，肾属水，对应冬季的阴气，肾虚时应当表现为热；肝属木，对应春季的阳气，肝虚时应当表现为冷。肾阴与肝阳，怎么可能同时出现虚证而表现为寒冷呢？或者笼统地说肝肾之中阴实阳虚，从而没有理由导致视物模糊。世俗之人胡乱认为肝肾之气衰少，不能上达于目。却不知道经典经文说热邪极盛会使人闭目（即眼黑），这难道是由寒邪引起的吗？又考察张仲景的说法，伤寒病中，热邪极盛时会让人神志不清，这就是目盲。《正理论》说：这是由于热邪极盛，郁结于眼部所导致的。如果眼睛看不见，耳朵听不见，全都是因为热邪郁结、玄府（汗孔及气液流通之微观孔隙）闭塞所致。气、津液、血脉、营卫、精神等，无法正常升降出入，因此根据郁结程度的轻重不同，表现出疾病的轻重差异。所以知道热邪郁结于眼部，会导致视物不见。如果眼睛轻微昏花，凑近看反而更难分辨物体，这是因为眼的玄府闭塞变小，就像隔着细绢看东西一样。有的人视物如见蝇翅飞舞，是因为玄府有所闭合。有的人眼睛昏花并看见黑点飘动，是因为热邪极盛而发于眼部。“亢则害，承乃制”（五行过亢则为害，需有制约方能平衡），于是反而出泪，气液浑浊，因为距离极近，所以即使微小的黑点也能看见如同黑花一般。以及迎风流泪且视力昏暗，是因为热邪极盛，被水气（肾水）所制约所致。所以经文说厥逆证会导致视物不见。人发生厥逆时，阳气并聚于上部，阴气并聚于下部。阳气并聚于上部，则火独旺于上；阴气并聚于下部，则足部寒冷，足冷则胀满。一水不能胜过五火，所以眼睛昏花甚至失明。因此迎风流泪不止。风邪侵袭眼部时，阳气内守于睛明穴周围，这是火气燔灼眼部，所以见到风就流泪。
按语：这段论述详细阐述了热邪极盛郁结、阴阳并厥、玄府闭塞导致眼病的缘由，其主旨在于火热之化。如果是由于饮食辛辣燥热、七情内伤、六淫之气淫溢郁结、气血虚实变化等原因，那么李东垣、张子和、陈无择等人的论述已经非常详尽。然而，也有因痰热、湿热，以及服用金石类燥热药物导致的。或者是久病之后，营卫虚弱，肝气肾阴不足，或者元气精气虚衰，以及脱营这类疾病，都有虚热和实热的区别，都应当分别治疗。
The *Yuan Bing Shi* (Treatise on the Origin of Diseases) states: Blurred vision, redness and swelling of the eyes, and ulcers or membranes on the eyelids are all caused by Heat. Additionally, ptosis (drooping of the eyelid), commonly known as "eye blacking," is also due to Heat. In cases where a person who previously had normal vision suddenly cannot see, it is because the pathogenic Heat is extremely severe and stagnant. Some claim that blurred vision is caused by deficiency-cold of the Liver and Kidney; this is erroneous. They rashly assert that the Liver opens into the eyes and the Kidney governs the pupils, thus falsely attributing blurred vision to deficiency-cold. However, the Kidney corresponds to Water and Winter Yin; when deficient, it should manifest as Heat. The Liver corresponds to Wood and Spring Yang; when deficient, it should manifest as Cold. How can Kidney Yin and Liver Yang simultaneously present as deficiency leading to cold? Or, broadly speaking, if there is excess Yin and deficiency Yang within the Liver and Kidney, there would be no basis for blurred vision. Laypeople rashly believe that the Qi of the Liver and Kidney is depleted and cannot reach the eyes. They fail to realize that the classic texts state that extreme Heat causes one to close their eyes (i.e., visual impairment/blackout), which is certainly not caused by Cold. Furthermore, examining Zhang Zhongjing's words, in Shanghan diseases (Cold Damage disorders), when Heat reaches its extreme, one becomes unrecognizable, which constitutes blindness. The *Zheng Li Lun* (Theory of Orthodoxy) states: This results from extreme Heat stagnating in the eyes. If the eyes cannot see and the ears cannot hear, it is entirely due to the stagnation of Heat and the closure of Xuanfu (micro-pores through which Qi and fluids circulate). Qi, body fluids, blood vessels, Ying-Wei (Defensive and Nutritive Qi), and Spirit cannot ascend, descend, enter, or exit properly. Consequently, the severity of the disease varies according to the degree of stagnation. Thus, we know that Heat stagnating in the eyes leads to loss of vision. If vision is slightly blurred, objects appear harder to distinguish when viewed up close, because the Xuanfu of the eyes have become small and closed, resembling viewing objects through fine silk. Those who see things like fly wings flying have some closure in their Xuanfu. Those whose vision is blurred and who see floating black spots do so because extreme Heat manifests in the eyes. According to the principle "Excess brings harm, and control restores balance" (Kang ze hai, cheng nai zhi), tears are produced in reaction. The turbidity of Qi and fluids makes them visible; since they are very close, even minute spots are seen as black flowers. When wind triggers tearing and dim vision, it is because extreme Heat is controlled by Water transformation. Hence, the classics state that Jue syndrome (reversal syndrome) causes loss of vision. In Jue syndrome, Yang Qi congregates in the upper body, and Yin Qi congregates in the lower body. Yang congregating above means Fire shines alone; Yin congregating below means the feet are cold, and cold feet lead to distension. One unit of Water cannot overcome five units of Fire; therefore, the eyes become dim and blind. Thus, tearing continues uncontrollably upon exposure to wind. When Wind invades the eyes, Yang Qi remains internally guarded around the Jingming acupoint; this is Fire blazing the eyes, causing tearing upon seeing wind.
Commentary: This discussion details the causes of eye diseases arising from extreme Heat stagnation, simultaneous Jue of Yin and Yang, and the closure of Xuanfu, emphasizing the transformation of Fire and Heat. If the cause lies in spicy and hot diet, emotional disturbances, excessive influence of the Six Evils (pathogenic factors), or deficiencies and excesses of Qi and Blood, the theories of Li Dongyuan, Zhang Hezi, and Chen Wuyue are already comprehensive. However, there are also cases caused by Phlegm-Heat, Damp-Heat, or the ingestion of mineral-based drying and heating medicines. Additionally, after prolonged illness, weakness of Ying-Wei, insufficiency of Liver Qi and Kidney Yin, decline of Yuan Qi (Original Qi) and Essence, or conditions such as Tuo Ying (depletion of nourishment) may occur. These present distinct differences between Deficiency-Heat and Excess-Heat, and each requires differentiated treatment.