天以六气生万物，其错综变化无形之妙用，愚者未易窥测，而人之受病，即从此而来。近人止知
六气太过曰六淫之邪，《内经》亦未穷极其变。夫六气伤人，岂界限清楚毫无兼气也哉！以六乘六，
盖三十六病也。夫天地大道之数，无不始于一，而成于三，如一三为三，三三如九，九九八十一，而黄
钟始备。六气为病，必再以三十六数，乘三十六，得一千二百九十六条，而外感之数始穷。此中犹
不兼内伤，若兼内伤，则靡可纪极矣。呜呼！近人凡见外感，主以一柴葛解肌汤，岂不谬哉！
治外感如将（兵贵神速，机圆法活，去邪务尽，善后务细，盖早平一日，则人少受一日之害）；治内
伤如相（坐镇从容，神机默运，无功可言，无德可见，而人登寿域）。治上焦如羽（非轻不举）；治
中焦如衡（非平不安）；治下焦如权（非重不沉）。
唐宋以来，治温热病者，初用辛温发表，见病不为药衰，则恣用苦寒，大队芩、连、知、柏，愈服愈
燥，河间且犯此弊。盖苦先入心，其化以燥，燥气化火，反见齿板黑，舌短黑，唇裂黑之象，火极而似
水也。吴又可非之诚是，但又不识苦寒化燥之理，以为黄连守而不走，大黄走而不守。夫黄连不可
轻用，大黄与黄连同一苦寒药，迅利于黄连百倍，反可轻用哉？余用普济消毒饮于温病初起，必去
芩、连，畏其入里而犯中下焦也。于应用芩、连方内，必大队甘寒以监之，但令清热化阴不令化燥。
如阳亢不寐，火腑不通等证，于酒客便溏频数者，
则重用之。湿温门则不惟不忌芩连，仍重赖之，盖欲其化燥也。语云∶“药用当而通神”，医者之于
药，何好何恶，惟当之是求。
天以风、寒、暑、湿、燥、火六气化生万物，其错综变化中无形的神妙作用，愚笨的人不容易窥探测度，而人之所以患病，正是由此而来。近代人只知道六气太过称为“六淫”之邪，《黄帝内经》也没有穷尽它的变化规律。六气伤人，难道界限清楚毫无兼夹之气吗！以六乘六，大概有三十六种病证。天地大道的数理，无不始于一，而成于三，如一三得三，三三得九，九九八十一，黄钟律吕才完备。六气致病，必然再以三十六数，乘以三十六，得到一千二百九十六条，外感病的数目才算穷尽。这中间还不包括内伤，如果兼夹内伤，那就多得无法记录了。唉！近代人凡是见到外感病，就主张只用一个柴葛解肌汤，这难道不荒谬吗！
治疗外感病要像将领（用兵贵在神速，策略圆融方法灵活，祛除病邪务必彻底，善后处理务必细致，因为早平复一天，人就少受一天的危害）；治疗内伤病要像宰相（坐镇从容，暗中运用神机，没有功劳可言，没有恩德可见，但让人进入长寿的境界）。治疗上焦病证要像羽毛（非轻清之品不能升举）；治疗中焦病证要像秤衡（非平和之剂不能安宁）；治疗下焦病证要像秤锤（非沉重之品不能下沉）。
唐宋以来，治疗温热病的人，起初使用辛温发表药，见病情不为药物所缓解，就肆意使用苦寒药，大队的黄芩、黄连、知母、黄柏，越服越燥，刘河间也犯过这种弊病。大概苦味先入心，其转化性质为燥，燥气化火，反而出现牙齿板黑、舌短黑、嘴唇裂黑等现象，这是火极似水的表现。吴又可反对这种做法确实正确，但他又不认识苦寒化燥的道理，认为黄连守而不走，大黄走而不守。黄连不可轻用，大黄与黄连同为苦寒药，效力比黄连猛烈百倍，反而可以轻用吗？我在使用普济消毒饮治疗温病初起时，必定去掉黄芩、黄连，是害怕它们入里而侵犯中下焦。在应当应用黄芩、黄连的方剂内，必定用大队甘寒药来制约它，只让它清热养阴而不让它化燥。如阳亢不寐、火腑不通等证候，对于酒客大便溏稀频数者，则重用黄芩、黄连。湿温门则不仅不忌讳黄芩、黄连，仍然严重依赖它们，大概是想要利用它们化燥的作用。俗话说：“药物使用得当就能通神”，医生对于药物，有什么喜好厌恶呢，只求用得恰当罢了。
Heaven generates all things with the Six Qi (Wind, Cold, Summer-heat, Dampness, Dryness, Fire), and its intricate changes possess a formless and miraculous function. The foolish find it difficult to fathom, yet human diseases arise precisely from this. Recent practitioners only know that excessive Six Qi is called the "Six Excesses" (Liu Yin) pathogenic factors; even the *Neijing* (Classic of Internal Canon) did not exhaustively explore its variations. When Six Qi injures humans, are their boundaries clear without any combined Qi? Multiplying six by six yields thirty-six types of diseases. The number of the Great Dao of Heaven and Earth begins with one and completes with three: one times three is three, three times three is nine, nine times nine is eighty-one, and then the Huangzhong (Yellow Bell) pitch-pipe is complete. For diseases caused by Six Qi, multiplying thirty-six by thirty-six yields one thousand two hundred ninety-six, thus exhausting the numbers of external contraction. This does not yet include internal injury; if internal injury is combined, the possibilities are incalculable. Alas! Recent practitioners, upon seeing any external contraction, advocate using only Chai Ge Jie Ji Tang (Bupleurum and Kudzu Decoction to Resolve the Muscle Layer); is this not absurd?
Treating external contraction is like being a general (speed is precious in warfare, strategies must be flexible and methods adaptable, expelling pathogens must be thorough, and post-treatment care must be meticulous; for every day earlier the condition is pacified, the person suffers less harm); treating internal injury is like being a prime minister (sitting calmly, silently operating the divine mechanism, no merit can be spoken of, no virtue visible, yet people enter the realm of longevity). Treating disorders of the Upper Jiao (Upper Burner) is like feathers (only light substances can lift); treating disorders of the Middle Jiao (Middle Burner) is like a balance scale (only balanced substances bring peace); treating disorders of the Lower Jiao (Lower Burner) is like a weight (only heavy substances can sink).
Since the Tang and Song dynasties, those treating warm-heat diseases initially use acrid-warm exterior-releasing herbs. Seeing that the disease is not alleviated by medicine, they recklessly use bitter-cold herbs, employing large doses of Huangqin (Scutellariae Radix), Huanglian (Coptidis Rhizoma), Zhimu (Anemarrhenae Rhizoma), and Huangbai (Phellodendri Cortex). The more they take them, the drier it becomes; even Liu Hejian fell into this fault. Bitterness first enters the Heart, and its transformation is dryness. Dryness Qi transforms into fire, manifesting as blackened teeth plates, short black tongue, and cracked black lips; this is extreme fire resembling water. Wu Keyou's opposition to this was indeed correct, but he failed to understand the principle of bitter-cold transforming into dryness, believing that Huanglian stays without moving, while Dahuang moves without staying. If Huanglian cannot be used lightly, and Dahuang is also a bitter-cold herb, yet is a hundred times more potent than Huanglian, can it be used lightly? When I use Puji Xiaodu Yin (Universal Safety Elixir to Relieve Toxicity) at the onset of warm diseases, I always remove Huangqin and Huanglian, fearing they will enter the interior and invade the Middle and Lower Jiao. In formulas where Huangqin and Huanglian should be applied, I always employ a large group of sweet-cold herbs to monitor them, ensuring they clear heat and nourish Yin without transforming into dryness. For conditions such as hyperactive Yang causing insomnia or blockage of the Fire Fu organs, in patients who are wine drinkers with loose stools and frequent defecation, I heavily use them. In the Damp-Warmth category, not only are Huangqin and Huanglian not taboo, but they are still heavily relied upon, presumably to utilize their drying properties. As the saying goes: "When medicines are used appropriately, they connect with the divine." Regarding medicines, what do physicians like or dislike? They only seek appropriateness.