夫医九流一技也，而回夭札与安乐，跻寿域而补造物之不逮，厥功博已，顾五行在手，则
夭可延，阴阳未分，则延者促已，审之在跬步，而适之则燕越，可畏哉。寒暑均天地之厉气，
伤寒伤暑二病，均厉气之能生杀人者，《素问》因寒因暑之说，昭昭为万世的。顾伤寒书创自
张长沙，详于朱南阳，而反复精析于陶节庵，其全书若眉列然，学人类能据籍按方而施治，故
往往取效。若伤暑一证，医书止列小款中，世皆忽之，一遇是证，率目为伤寒，以发散等剂投
之，间加衣被取汗，甚灸以致伤生者，累累不悟，可不悲欤！予诸生时，万历戊子夏患兹证，
势极气索，瞀然自愦，庸医以为脾胃内伤，或以为劳役中折，几不自持，徽医汪韫石适在旁，
蹙然曰∶心烦面垢，此暑证也。何多指，闻之皆骇其名，予于瞀中微解根据之，服益元散二剂而
苏，仍调以加味香薷饮数剂而愈。遂着《伤寒伤暑辨》一篇。刊于暑月印布，兼施药饵，其捷
效若谷响，乃发愿搜罗群书，着为全帙以济世。惧阅历未久不中 ，期五十以后方就笔研，戊
申自计部以目恙请告，杜门静摄，得毕志于性命黄老诸家，昕夕 ，无逸晷暇，即焚香兀坐，
间入圜内视，百日不他，及目愈后，至天启壬戌，感仙师教，就笔研挟古诸名家，参考编集而
成帙。拮 十余载，约二万余千言，分为上下两卷，议论皆常语，不敢钩深，以便医家览解，
方多遵古无他奇，宜证则灵，菽粟岂珍错，而食其时，百骸理宜也。要在于燕越歧路处着力耳，
平高贡，除妒忌，澄心察理，审证投咀，医之上计乎。宁独医人一心耳。虚与实相反，拗与圆
相仇，古今成败之大关也。秉国成者，与谋国计者，身系社稷安危，操万姓命脉，虚心圆智，
盖可忽乎哉！予因医而广其说。
天启三年岁次癸亥孟夏朔旦赐进士出身奉政大夫户部陕西司郎中颖郡张鹤腾撰
医学不过是九流中的一门技艺，然而它能挽救夭折、带来安乐，使人达到长寿的境界，弥补造物主的不足，其功德可谓博大。但是，如果五行生克掌握在手，夭折可以延长寿命；如果阴阳未能分清，原本可延长的寿命也会变得短促。审慎在于细微之处，而一旦失误，结果便如燕地与越地般天差地别，这难道不值得敬畏吗？
寒气和暑气都是天地间的厉气（指具有强烈致病性的气候因素），伤寒和伤暑这两种病，都是由厉气能够致人死亡或救人性命的疾病。《素问》中关于因寒、因暑的论述，清晰明确，足以成为万世的准则。然而，关于伤寒的著作创始于张仲景（张长沙），在朱肱（朱南阳）那里得到详述，又在陶华（陶节庵）那里经过反复精细分析，全书条理清晰如同眉目罗列一般，学习的人大都能依据书籍、按照方剂进行治疗，所以往往能取得疗效。
至于伤暑这一证候，医书中只列为小条目，世人都轻视它。一旦遇到这种病症，大多误认为是伤寒，使用发散类的药剂投治，有时甚至加盖衣被以求出汗，更有甚者通过艾灸导致伤害甚至丧生的情况，屡见不鲜且不知醒悟，这难道不可悲吗！
我在做诸生（读书人）时，万历戊子年夏天患上了这种病，病情极重，气息微弱，神志昏乱糊涂。庸医认为这是脾胃内伤，有的认为是劳役过度导致的折损，我几乎无法支撑自己。徽州医生汪韫石恰好在一旁，皱着眉头说：“心烦、面色污垢，这是暑证。”为什么这么多医生指认错误？听到的人都对他的诊断感到惊骇。我在昏乱之中稍微清醒了一些，依据他的判断，服用益元散两剂后苏醒，随后又用加味香薷饮调理数剂而痊愈。于是撰写了《伤寒伤暑辨》一篇文章，在暑月期间刊印散发，并兼施药物，其效果迅速如同山谷回响。于是我发愿搜罗各类书籍，著成完整的卷帙以救济世人。
我担心阅历尚浅不能切中要害，计划到五十岁以后才动笔研墨。戊申年，我从户部官员职位上因眼疾请假回乡，闭门静养，得以专心研读性命、黄帝内经及老子等各家学说，早晚沉浸其中，没有片刻闲暇，即使焚香独自静坐，偶尔进入圆通境界向内观照，百日之内心无旁骛。等到眼睛痊愈后，直到天启壬戌年，感念仙师教诲，便在书案前挟带古代各位名家的著作，参考编集而成此卷。
经过十余年的努力，大约两万余字，分为上下两卷。其中的议论都是平常话语，不敢深究玄奥，以便医家阅读理解。方剂大多遵循古法，没有特别奇特的，但适合证候就能显灵，就像菽粟（豆类谷物）虽然普通，但在适当的时候食用，百骸自然理顺。关键在于要在燕越歧路（比喻生死攸关的关键选择处）着力罢了。保持平和谦逊，去除嫉妒之心，澄清内心以察理，审慎辨证后投药，这是医者的上策吧。这不仅关乎医者的一心而已。虚与实是相反的，拗与圆是相仇的，这是古今成败的大关键。执掌国家政权的人，与谋划国事的人，身体系着社稷的安危，操持着万千百姓的命脉，若能虚心且具备圆融的智慧，难道可以忽视吗！我因此由医学而推广了这一说法。
天启三年，岁次癸亥，孟夏初一，赐进士出身、奉政大夫、户部陕西司郎中、颖郡人张鹤腾撰。
Medicine is but one of the nine schools of thought, yet it can rescue those from premature death and bring peace and health, elevating people to a realm of longevity and compensating for the deficiencies of Creation; its merit is indeed vast. However, if the Five Phases (Wu Xing) are mastered, premature death can be prolonged; if Yin and Yang are not clearly distinguished, a life that could have been extended will become short. Prudence lies in the smallest steps, yet a slight error leads to results as distant as those between Yan and Yue; how awe-inspiring this is!
Cold and heat are both pernicious qi (pathogenic climatic factors) of Heaven and Earth. The diseases of Cold Injury (Shanghan) and Heat Injury (Shangshu) are both capable of causing death or saving lives through these pernicious qi. The theories in *Suwen* regarding etiology by cold and heat are clear and serve as a standard for all generations. However, treatises on Cold Injury were initiated by Zhang Zhongjing (Zhang Changsha), detailed by Zhu Gong (Zhu Nanyang), and subjected to repeated, precise analysis by Tao Hua (Tao Jie'an). Their complete works are as clear as rows of eyebrows, allowing students to rely on texts and follow prescriptions for treatment, thus often achieving efficacy.
As for the syndrome of Heat Injury, medical books list it only as a minor item, and the world generally neglects it. Upon encountering such a case, practitioners usually mistake it for Cold Injury and administer dispersing formulas. Sometimes, patients are covered with extra clothing and blankets to induce sweating, and in severe cases, moxibustion causes injury or even death. Such instances occur frequently without realization; is this not tragic?
When I was a student, in the summer of the Wuzi year of the Wanli era, I suffered from this disease. My condition was critical, with weak breath and confused mind. Quack doctors believed it was an internal injury to the Spleen and Stomach, while others attributed it to exhaustion from labor. I could barely sustain myself. Dr. Wang Yunshi from Huizhou happened to be nearby. Frowning, he said, "Heart vexation and a greasy facial complexion indicate a Heat Injury syndrome." Why did so many misdiagnose? Those who heard his diagnosis were startled. In my confusion, I gained slight clarity and followed his advice. After taking Yiyuan San (Benefit Prime Powder) for two doses, I regained consciousness, and subsequently recovered after several doses of Jiawei Xiangru Yin (Modified Elsholtzia Decoction). Thus, I wrote an article titled "Differentiation of Cold Injury and Heat Injury," which was printed and distributed during the hot months, along with the administration of medicine. Its rapid effect was like an echo in a valley. I then vowed to collect various books and compile a complete volume to benefit the world.
Fearing that my experience was insufficient to hit the mark, I planned to begin writing only after age fifty. In the Wushen year, I requested leave due to eye trouble while serving as a Director in the Shaanxi Department of the Ministry of Revenue. Secluding myself for quiet recuperation, I devoted myself to studying the teachings of Life and Nature, as well as the Huangdi Neijing and Laozi. Day and night, immersed in study with no leisure, I would burn incense and sit alone, occasionally entering a state of inner vision within the circle of enlightenment, remaining undistracted for a hundred days. After my eyes healed, until the Renxu year of the Tianqi era, inspired by the teaching of an Immortal Master, I sat at my desk with ancient masters' works, referencing and compiling them into this volume.
After more than ten years of effort, comprising approximately twenty thousand characters, divided into upper and lower volumes, the discussions consist of common language, avoiding profound obscurity to facilitate understanding by physicians. The formulas mostly adhere to ancient methods without novelty, but they are effective when suited to the syndrome. Just as beans and millet are ordinary yet nourishing when consumed at the right time, restoring harmony to the body, the key lies in exerting effort at the crossroads of life and death (like the divergence between Yan and Yue). Maintaining humility, eliminating jealousy, clarifying the mind to observe principles, and carefully differentiating syndromes before prescribing medication constitute the highest strategy of medicine. This concerns not only the physician's heart. Deficiency and Excess are opposites; rigidity and flexibility are conflicting; these are the major keys to success and failure in ancient and modern times. Those who hold state power and those who plan national affairs bear the safety of the nation and the lifelines of the people. Can their humble hearts and flexible wisdom be ignored? Therefore, I extend this discussion from medicine.
Written by Zhang Heteng, a Jinshi degree recipient, Fengzheng Dafu (Counselor), Director of the Shaanxi Department of the Ministry of Revenue, from Ying Commandery, on the first day of the first month of the Tianqi Era, Year Guihai.