阳中之阴水。太阳是也。为三阳之首。能巡经传。亦越经传。
阳中之阳土。阳明是也。夫阳明为中州之土。主纳而不出。如太阳传至此。名曰巡经传
也。
阳中之阳木。少阳是也。上传阳明。下传太阴。如太阳传至此。为越经传也。
阴中之阴土。太阴是也。上传少阳为顺。下传少阴为逆。此为土下传也。如太阴传太阳
。为误下
传也。阴中之阳水少阴是也。上传太阴为顺。下传厥阴为生。如太阳传至此乃表传里也。
阴中之阴木。厥阴也。上传少阴为实。再传太阳为自愈也。
太阳者乃巨阳也。为诸阳之首。膀胱经病若渴者。自入于本也。名曰传本。
太阳传阳明胃土者。名曰巡经传。为发汗不彻利小便。余邪不尽透入于里也。
太阳传少阳胆木者。名曰越经传。为元受病脉浮无汗。当用麻黄而不用之故也。
太阳传少阴肾水者。名曰表传里。为得病急当发汗而反下汗不发所以传也。
太阳传太阴脾土者。名曰误下传。为元受病脉缓有汗。当用桂枝。而反下之所致也。当
时腹痛四肢沉重。
太阳传厥阴肝木者。为三阴不至于首唯厥阴与督脉上行与太阳相接。名曰巡经得度传。
太阳证。头项痛。腰脊强。发热恶寒无汗。脉尺寸俱浮而紧。是发于阳阳者卫也（麻黄
汤）主之。
麻黄（一两半去节） 桂枝（一两去皮） 杏仁（二十粒汤浸去皮尖） 甘草（半两炙）
上锉每服五钱。水一盏煎温服。
太阳证。头项痛。腰脊强。发热恶寒自汗。脉尺寸俱浮而缓者。荣也。（桂枝汤）主之。
桂枝（去皮） 芍药 甘草（各等分）
上锉。每服八钱。水一盏半。姜枣同煎温服。
属阳中的阴水，指的是太阳经。它位居三阳之首，病邪可以沿着经络顺序传变（巡经传），也可以跨越经络传变（越经传）。
属阳中的阳土，指的是阳明经。阳明属于中焦的土，主要功能是受纳而不外泄。如果病邪从太阳经传到此处，称为循经传。
属阳中的阳木，指的是少阳经。病邪向上可传至阳明，向下可传至太阴。如果病邪从太阳经直接传到此处，称为越经传。
属阴中的阴土，指的是太阴经。病邪向上传给少阳为顺证，向下传给少阴为逆证，这属于土行的下传。如果太阴经的病邪再传回太阳经，则属于误用攻下法导致的传变。属阴中的阳水，指的是少阴经。病邪向上传给太阴为顺证，向下传给厥阴为生路。如果病邪从太阳经传到此处，属于由表入里的传变。
属阴中的阴木，指的是厥阴经。病邪向上传给少阴为实证，如果再传回太阳经，病情就会自愈。
太阳经又称巨阳，是诸阳经的首领。膀胱经受邪若出现口渴症状，说明病邪已传入本经，称为“传本”。
太阳经病邪传入阳明胃土，称为“巡经传”，这是因为发汗不彻底且利小便，导致残余邪气未能尽除而透入体内。
太阳经病邪传入少阳胆木，称为“越经传”，这是因为初感病邪时脉象浮而无汗，应当使用麻黄汤却未使用的缘故。
太阳经病邪传入少阴肾水，称为“表传里”，这是因为患病急迫本当发汗，反而误用攻下法，导致汗不得出从而发生传变。
太阳经病邪传入太阴脾土，称为“误下传”，这是因为初感病邪时脉缓有汗，应当使用桂枝汤却反而误用攻下法所致。当时会出现腹痛、四肢沉重等症状。
太阳经病邪传入厥阴肝木，是因为三阴经一般不到达头部，唯独厥阴经与督脉上行并与太阳经相接，这种情况称为“巡经得度传”。
太阳经证候表现为：头痛项强，腰脊僵硬，发热恶寒无汗，寸关尺三部脉象均呈现浮紧之象。这是发于阳分，影响卫气（应使用麻黄汤）主治。
药材组成：麻黄（一两半，去节）、桂枝（一两，去皮）、杏仁（二十粒，热水浸泡后去皮尖）、甘草（半两，炙）。
以上药物切碎，每次服用五钱，加水一盏煎煮，温服。
Yin water within Yang refers to the Taiyang (Greater Yang) channel. It stands as the head of the Three Yang channels, capable of transmitting along the meridian sequence (Xunjing chuan) or skipping meridians (Yuejing chuan).
Yang earth within Yang refers to the Yangming (Bright Yang) channel. Yangming constitutes the earth of the Central Pivot, governing reception without excretion. If transmission reaches this stage from Taiyang, it is termed Xunjing chuan (transmission along the meridian sequence).
Yang wood within Yang refers to the Shaoyang (Lesser Yang) channel. Transmission proceeds upward to Yangming and downward to Taiyin. If transmission reaches this stage directly from Taiyang, it is termed Yuejing chuan (skipping-meridian transmission).
Yin earth within Yin refers to the Taiyin (Greater Yin) channel. Upward transmission to Shaoyang is considered favorable (Shun), while downward transmission to Shaoyin is adverse (Ni); this constitutes downward transmission of Earth. If Taiyin transmits back to Taiyang, it results from erroneous purgation (Wuxia chuan). Yang water within Yin refers to the Shaoyin (Lesser Yin) channel. Upward transmission to Taiyin is favorable; downward transmission to Jueyin leads to recovery. Transmission from Taiyang to this stage represents interiorization from the exterior (Biao chuan Li).
Yin wood within Yin refers to the Jueyin (Terminal Yin) channel. Upward transmission to Shaoyin indicates excess; subsequent transmission back to Taiyang leads to spontaneous resolution.
Taiyang, also known as Ju Yang (Giant Yang), is the leader of all Yang channels. In Bladder channel disease, if thirst occurs, the pathogen has entered its root channel, termed Chuan Ben (Transmission to the Root).
Transmission from Taiyang to Yangming Stomach Earth is termed Xunjing chuan. This arises because sweating was incomplete and diuresis was induced, leaving residual pathogens that penetrated inward.
Transmission from Taiyang to Shaoyang Gallbladder Wood is termed Yuejing chuan. This occurred because the initial presentation featured a floating pulse and absence of sweat, requiring Mahuang Tang (Ephedra Decoction), which was not administered.
Transmission from Taiyang to Shaoyin Kidney Water is termed Biao chuan Li. This resulted from an urgent onset requiring sweating, but purgation was erroneously applied instead, preventing sweat release and causing transmission.
Transmission from Taiyang to Taiyin Spleen Earth is termed Wuxia chuan. This occurred because the initial presentation featured a moderate pulse and sweating, requiring Guizhi Tang (Cinnamon Twig Decoction), yet purgation was erroneously applied. Symptoms at that time included abdominal pain and heaviness in the four limbs.
Transmission from Taiyang to Jueyin Liver Wood occurs because the Three Yin channels generally do not reach the head; only Jueyin ascends via the Du Mai (Governor Vessel) to connect with Taiyang. This is termed Xunjing dedu chuan.
Taiyang syndrome manifests as headache and stiffness of the neck and occiput, stiffness of the lower back and spine, fever, aversion to cold, and absence of sweat. The pulse is floating and tight in both cun and chi positions. This indicates onset in Yang affecting the Wei (Defensive) level, treated primarily with Mahuang Tang (Ephedra Decoction).
Ingredients: Ephedrae Herba (Mahuang, 麻黄) 1.5 liang (devoid of nodes), Cinnamomi Ramulus (Guizhi, 桂枝) 1 liang (devoid of bark), Armeniacae Semen Amarum (Xingren, 杏仁) 20 grains (soaked in hot water, devoid of skin and tips), Glycyrrhizae Radix et Rhizoma (Gancao, 甘草) 0.5 liang (prepared by honey-frying).
Crush the ingredients. Take 5 qian per dose, decoct in one cup of water, and take warm.
Taiyang syndrome manifests as headache and stiffness of the neck and occiput, stiffness of the lower back and spine, fever, aversion to cold, and spontaneous sweating. The pulse is floating and moderate in both cun and chi positions. This indicates disharmony of the Ying (Nutritive) level, treated primarily with Guizhi Tang (Cinnamon Twig Decoction).
Ingredients: Cinnamomi Ramulus (Guizhi, 桂枝) (devoid of bark), Paeoniae Radix Alba (Shaoyao, 芍药), Glycyrrhizae Radix et Rhizoma (Gancao, 甘草) (equal parts).
Crush the ingredients. Take 8 qian per dose, decoct in one and a half cups of water with fresh ginger and jujube, and take warm.