论小柴胡汤
天师曰∶轻者，病不重，不必重治，而用轻剂以治之也。如人咳嗽、头痛、眼目痛。口舌生疮，皆
是小症，何必用重剂以补阳，用浓味以滋阴哉。法当用轻清之品，少少散之，无不立效，如小柴胡之方是
也。然而小柴胡汤，世人不知轻重之法，予再酌定之，可永为式。方用柴胡一钱，黄芩一钱，半夏一钱，陈
皮五分，甘草一钱，此小柴胡汤。予更加人参五分，茯苓二钱，更为奇妙。盖气足则邪易出，而汗易发。
世人见用人参，便觉失色，匪独医者不敢用、即病者亦不敢服。相沿而不可救药者，滔滔皆是，安得
布告天下医人，详察其病源，而善用之也。此轻治之法，极宜究心。
张公曰∶天师言小柴胡汤，治外感者也。予言治内伤者，补中益气汤是也。然补中益气汤，东垣立
方之后，世人乱用，殊失重轻之法。予再酌定之，可传之千古不敝。柴胡一钱，升麻四分，黄 三钱，白
术三钱，当归三钱；陈皮八分，甘草一钱，人参一钱，人气虚者多加，可至一两，看人之强弱分多寡
耳。（〔批〕酌定补中益气汤。）若有痰，加半夏一钱；有热，加黄芩一钱；有寒，加桂枝一钱；头
痛，加蔓荆子八分，或川芎一钱；两胁痛，加白芍三钱；少腹痛，亦加白芍三钱∶有食，加麦芽二钱；
伤肉食，加山楂二十粒；胸中痛，加枳壳五分，神曲五分。如此加用，自合病机。无如人不肯用此方以治
内伤也，法最宜留心。大约右手寸口脉与关脉大于左手之脉者、急用此汤，无不神效。
（小柴胡本是半表半里少阳经药，内用参苓，以病在少阳，恐渐逼里，乘之于所胜也。故先扶胃气，
使邪不入而已，入者亦得正旺而自退耳。李子永识。）
On Xiao Chai Hu Tang (Minor Bupleurum Decoction)
The Heavenly Master said: "Light treatment" refers to conditions that are not severe, where heavy medication is unnecessary; instead, light and clear agents should be used for treatment. For instance, if a person suffers from coughing, headache, eye pain, or sores in the mouth and tongue, these are all minor symptoms. Why use heavy agents to tonify Yang or rich-flavored substances to nourish Yin? The method should employ light and clear herbs, administered in small doses to disperse the pathogen, which will invariably yield immediate results. Xiao Chai Hu Tang (Minor Bupleurum Decoction) is such a formula. However, people today do not understand the principle of distinguishing between heavy and light treatments. I have further refined this prescription, which can serve as a permanent standard. The formula consists of Chai Hu (Bupleuri Radix) 1 qian, Huang Qin (Scutellariae Radix) 1 qian, Ban Xia (Pinelliae Rhizoma Preparatum) 1 qian, Chen Pi (Citri Reticulatae Pericarpium) 5 fen, and Gan Cao (Glycyrrhizae Radix et Rhizoma) 1 qian. This constitutes Xiao Chai Hu Tang (Minor Bupleurum Decoction). I further add Ren Shen (Ginseng Radix et Rhizoma) 5 fen and Fu Ling (Poria) 2 qian, making it even more effective. When Qi is sufficient, pathogens are easily expelled, and sweat is readily produced. People often turn pale upon seeing the use of Ren Shen (Ginseng Radix et Rhizoma); not only do physicians dare not use it, but patients also dare not take it. Such entrenched errors are ubiquitous and incurable. How can we widely inform physicians throughout the world to carefully examine the source of diseases and utilize this method effectively? This method of light treatment requires deep study.
Master Zhang said: "The Heavenly Master's discussion on Xiao Chai Hu Tang (Minor Bupleurum Decoction) pertains to external contraction. My discussion on Bu Zhong Yi Qi Tang (Tonify the Middle and Augment the Qi Decoction) pertains to internal injury. However, since Li Dongyuan established Bu Zhong Yi Qi Tang (Tonify the Middle and Augment the Qi Decoction), people have misused it indiscriminately, completely losing the principle of weighing severity. I have further refined it, so it may endure forever without degradation. The formula uses Chai Hu (Bupleuri Radix) 1 qian, Sheng Ma (Cimicifugae Rhizoma) 4 fen, Huang Qi (Astragali Radix) 3 qian, Bai Zhu (Atractylodis Macrocephalae Rhizoma) 3 qian, Dang Gui (Angelicae Sinensis Radix) 3 qian; Chen Pi (Citri Reticulatae Pericarpium) 8 fen, Gan Cao (Glycyrrhizae Radix et Rhizoma) 1 qian, and Ren Shen (Ginseng Radix et Rhizoma) 1 qian. For those with deficient Qi, the dosage of Ren Shen (Ginseng Radix et Rhizoma) can be increased up to 1 liang, depending on the patient's strength. ([Comment] Refined Bu Zhong Yi Qi Tang (Tonify the Middle and Augment the Qi Decoction)). If there is phlegm, add Ban Xia (Pinelliae Rhizoma Preparatum) 1 qian; if there is heat, add Huang Qin (Scutellariae Radix) 1 qian; if there is cold, add Gui Zhi (Cinnamomi Ramulus) 1 qian; for headache, add Man Jing Zi (Viticis Semen) 8 fen or Chuan Xiong (Ligustici Chuanxiong Rhizoma) 1 qian; for pain in both hypochondria, add Bai Shao (Paeoniae Radix Alba) 3 qian; for lower abdominal pain, also add Bai Shao (Paeoniae Radix Alba) 3 qian; for food stagnation, add Mai Ya (Hordei Fructus Germinatus) 2 qian; for meat injury, add Shan Zha (Crataegi Fructus) 20 grains; for chest pain, add Zhi Ke (Aurantii Fructus Immaturus) 5 fen and Shen Qu (Massa Medicata Fermentata) 5 fen. Such modifications naturally align with the pathology. Unfortunately, people are unwilling to use this formula for internal injuries. One must pay close attention to this method. Generally, if the Cun (Inch) and Guan (Bar) pulses on the right hand are larger than those on the left hand, this decoction should be used urgently, yielding miraculous effects.
(Note: Xiao Chai Hu Tang (Minor Bupleurum Decoction) originally treats Shaoyang disease located at the half-exterior and half-interior level. The inclusion of Ren Shen (Ginseng Radix et Rhizoma) and Fu Ling (Poria) inside is because when the pathogen is in the Shaoyang channel, there is fear that it will gradually penetrate inward, attacking the organ it overcomes (Earth/Spleen-Stomach). Therefore, one first supports Stomach Qi to prevent the pathogen from entering; if it does enter, the righteous Qi will be strong enough to expel it spontaneously. Recorded by Li Ziyong.)