典藏书目

The essential principles state: When the disease is in the fu organs, it is a exterior syndrome; one should dispel wind and clear heat. When the disease is in the zang organs, it is an interior syndrome; one should nourish blood and calm the spirit. Sudden onset constitutes an exterior syndrome and is easy to treat; chronic illness constitutes an interior syndrome and is difficult to cure.

Zihe said: Although the Sages stated that "the eyes see when they receive blood," blood can also be excessive or deficient. Excess leads to obstruction in the eyes causing pain; if not relieved, it leads to exhaustion of the eyes and blindness. Deficiency leads to consumption of vision and eventual blindness. Therefore, young people often have excess blood, while old people often have deficient blood. However, among young people, there are no cases of deficiency; among old people, there are still cases of excess. This must be carefully observed. The inner canthus is where the Foot-Taiyang Bladder Channel begins; here, blood is abundant and qi is scarce. The outer canthus belongs to the Foot-Shaoyang Gallbladder Channel; here, blood is scarce and qi is abundant. The upper eyelid is governed by the Foot-Taiyang Bladder Channel; here, blood is abundant and qi is scarce. The lower eyelid is governed by the Foot-Yangming Stomach Channel; here, both blood and qi are abundant. However, the Foot-Yangming Stomach Channel originates from beside the eyes, intersects at the root of the nose, and converges with the Taiyang and Shaoyang channels at the eyes. Only the Foot-Jueyin Liver Channel connects directly to the eye system. Thus, blood excess belongs to the excess syndromes of the Taiyang and Yangming channels; blood deficiency belongs to the deficiency syndrome of the Jueyin channel. Therefore, bloodletting is suitable for the Taiyang and Yangming channels because these two channels have abundant blood. The Shaoyang channel should not be bled because its blood is scarce. Bleeding the Taiyang and Yangming channels will clarify the eyes; bleeding the Shaoyang channel will darken the eyes. One must know not to allow excess or deficiency, but rather to use blood to nourish the eyes. Generally speaking, too much blood causes flooding, while too little causes withering. Heat accelerates blood flow and increases volume; cold slows blood flow and decreases volume. This is a constant principle. The eyes are the external manifestation of the Liver; the Liver governs the eyes and belongs to Wood in the Five Elements. Although excessive growth of wood obscures vision and decay causes withering, the five wheels of the eye represent the essence of the five zang and six fu organs and are the gathering point of the master vessels. The white part (Sclera) belongs to Lung Metal; the flesh wheel (Eyelids) belongs to Spleen Earth; the red vessels belong to Heart Fire; the black water and divine light (Pupil and Vision) belong to Kidney Water and also relate to Liver Wood. These are known to the secular world. Yet, when eye diseases occur, people do not understand the pathology. How do we know it is not caused by Fire? If the white part turns red, it is Fire attacking the Lung. If the eyelids turn red and swell, it is Fire attacking the Spleen. If the black water and divine light are obscured by membranes, it is Fire attacking the Liver and Kidney. If red vessels penetrate the eye, Fire is extremely strong. Treating Fire resolves the issue in one sentence. Thus, the *Neijing* states: "When heat prevails, swelling occurs." Any sudden redness and swelling of the eyes, photophobia, dullness and astringency, unceasing tearing, or sudden blinding due to cold are all caused by excessive heat. The method to treat Fire involves using salty-cold herbs, employing emesis or purgation methods. In acupuncture, points Shenting (GV24), Shangxing (GV23), Xinhui (GV16), Qianding (GV20), and Baihui (GV20) are used. Blood nevi can be made to recede immediately; pain can be stopped immediately; dimness can be clarified immediately; swelling can be eliminated immediately. However, children should not have the Xinhui point needled because the tissue is thin and bone injury may occur. Children have Water above and Fire below, so their vision is clear; the elderly have Fire above and insufficient Water, so their vision is dim. The *Neijing* states: "For blood excess, one should drain it." Another classic states: "Tonify deficiency, reduce excess." Conditions like night blindness (Aurora Nuxia) and internal cataracts are caused by violent anger or great sorrow, resulting in Liver-related blood deficiency. Bleeding is contraindicated; one should only tonify the Liver and nourish the Kidney. For sudden redness, swelling, and pain, one should bleed the aforementioned five acupoints with a needle. Subsequently, apply salted oil to the hair roots. In severe cases, this may be repeated two or three times. Adjust according to the severity of the condition until balance is achieved.

Commentary: This refers to the urgency of bloodletting for eye diseases, applicable to initial acute heat-pain attacks or chronic stagnation, requiring venting with a three-edged needle. However, for the elderly, those with chronic deficiency, or those with qi stagnation, mild needle tonification and reduction techniques are appropriate. Thus, Zihe's remarks were general. Regarding the Shaoyang channel, bleeding is not recommended to avoid excess or deficiency, aiming instead to nourish the eyes with blood. This intention is evident.