司天主一岁之天。在泉主一岁之地。司天又主上半年。在泉又主下半年。司天又主初之
气。
在泉又主终之气。左右间是阴阳路。每到六旬移一步。司天三位以兹分。时位初终随度数。
司天生运父临子。名为顺化当如此。运生司天子临父。名为小逆倒之故。司天克运号天
刑。
大过天刑运反平。五运若犯司天克。当分太少观差忒。少运胜天为不和。太运胜天为太运。
少运胜天或天胜。其位反同天正化。顺化小逆无胜负。此由运与天和睦。天刑不和与天逆。
灾变分争想非一。三者皆从何处来。运与司天不相得。运同天化是相符。名逐加临与消息。
法以四年为一纪。年遇三合周复始。申子辰为初六天寅子亥酉申午起。巳酉丑为六二天
。
蛇兔虎鼠猪鸡里。寅午戌为六三天。申午巳卯寅子是。亥卯未为六四天。定入晡早禺出尔。
每
气六十日方换。常余八十七刻半。初三与五欲交时。从初一刻根据期算。二四与六欲交时。从
申定刻随时断。二十四步百刻周。方成一度如鱼贯。前三十日谓之初。天气用时地气伏。后
三十日谓之中。地气用时天来从。天用事则地气上。地用事则天气降。地气升时入太虚。天
气降时入有质。升而已降降而升。升降相因变乃出。凡言天者求之本。风暑火湿燥寒附。凡
言地者求之位。二火土木金水议。凡言人者求气交。多少常差其分际。天气不足地气随。地
气不足天气来。运居其中常先应。归所同和恶不胜。上胜天气降而下。下胜地气迁而上。微
者小瘥甚大瘥。佐易变生观病状。
司天主管一年的天气，在泉主管一年的地气。司天又主管上半年的气候，在泉又主管下半年的气候。司天又主管初之气（一年六步气的第一步），在泉又主管终之气（一年六步气的最后一步）。左右间气是阴阳运行的路径，每过六十天移动一步。司天的三位（初之气、中运、终之气等位置）由此划分，时位的开始和结束随着度数的变化而确定。
大运生司天之气，且地支相合（如甲己土运遇子丑年），称为“顺化”，应当如此。大运被司天所生，或大运克制司天（此处原文“运生司天子临父”表述较晦涩，结合上下文及《素问》理论，通常指运与天关系中的“小逆”情况，即运生天或天克运等复杂关系，此处依字面意译并保留术语逻辑：若大运生司天，或司天之子临大运之父母位，称为“小逆”，这是颠倒的缘故）。司天之气克制大运，称为“天刑”。如果是大过之年遇到天刑，大运反而趋于平和。如果五运侵犯司天之气而被克制，应当区分大运的“太少”（少运为不及，太运为太过）来观察差异。少运（不及之运）胜过司天，称为“不和”；太运（太过之运）胜过司天，仍称为“太运”。无论是少运胜过司天，还是司天胜过少运，其位置反而同于“天正化”（正常的化育规律）。顺化和小逆没有胜负之争，这是因为大运与司天和睦相处。天刑是不和，天逆则是灾变，分争的情况可能不止一种。这三种情况（顺化、小逆、天刑/逆）都从哪里来呢？是因为大运与司天不相得（不和谐）。大运与司天之化相符，名字上遵循加临与消长的规律。
推算方法以四年为一纪，年份遇到三合局则循环重新开始。申子辰年为初六天，从寅、子、亥、酉、申、午起算；巳酉丑年为六二天，从蛇（巳）、兔（卯）、虎（寅）、鼠（子）、猪（亥）、鸡（酉）里起算；寅午戌年为六三天，从申、午、巳、卯、寅、子是起算；亥卯未年为六四天，确定进入晡时（下午3-5点）、早时、禺时（上午9-11点）而出。每步气六十天方更换，常剩余八十七刻半。初三与初五想要交接的时候，从初一刻根据日期推算。初二、初四与初六想要交接的时候，从申定刻随时判断。二十四步气共一百刻周流，才形成一度，如同鱼贯而行。前三十天称为“初”，此时天气用时，地气潜伏；后三十天称为“中”，此时地气用时，天气随从。天气用事则地气上升，地气用事则天气下降。地气上升时进入太虚（无形之境），天气下降时进入有质（有形之物）。升了之后降，降了之后升，升降相互因果，变化由此产生。凡是谈论天的，要探求其根本，风、暑、火、湿、燥、寒依附于天。凡是谈论地的，要探求其位置，二火、木、土、金、水议论于地。凡是谈论人的，要探求气交之处，多少常有差别的界限。天气不足，地气随之补充；地气不足，天气前来援助。大运居于其中，常常先应验。归于相同和谐的状态，厌恶不胜任的情况。上面胜则天气降而下，下面胜则地气迁而上。轻微的病会稍微好转，严重的病会大大恶化。辅助药物容易改变病情，需观察病状。
Si Tian (Master of the Heaven) governs the celestial qi of a year, and Zai Quan (Master of the Earth) governs the terrestrial qi of a year. Si Tian also governs the first half of the year, while Zai Quan governs the second half. Si Tian further governs the First Qi (the first step of the six qi phases in a year), and Zai Quan governs the Final Qi (the last step). The Left and Right Interstitial Qi (Jian Qi) are the pathways of Yin and Yang; every sixty days, they shift one step. The three positions of Si Tian are divided accordingly, and the beginning and end of time positions follow the degrees.
When the Yun (Great Movement/Five Movements) generates Si Tian, and the Earthly Branches harmonize (e.g., Jia/Ji Earth Yun meeting Zi/Chou years), it is named "Shun Hua" (Smooth Transformation), which should be so. When Yun is generated by Si Tian, or when the Son position of Yun faces the Father position of Si Tian, it is named "Xiao Ni" (Minor Rebellion), due to inversion. When Si Tian controls Yun, it is called "Tian Xing" (Heavenly Punishment). In a Da Guo (Excessive) year encountering Tian Xing, the Yun tends to become balanced. If the Five Yun offend Si Tian and are controlled by it, one must distinguish between Shao Yun (Deficient Movement) and Tai Yun (Excessive Movement) to observe discrepancies. If Shao Yun overcomes Si Tian, it is called "Bu He" (Dis harmony); if Tai Yun overcomes Si Tian, it remains called "Tai Yun". Whether Shao Yun overcomes Si Tian or Si Tian overcomes Shao Yun, its position resembles "Tian Zheng Hua" (Normal Heavenly Transformation). Shun Hua and Xiao Ni have no victory or defeat, because Yun and Si Tian are harmonious. Tian Xing represents dis harmony, and Tian Ni (Heavenly Rebellion) brings disasters and changes, which may vary. Where do these three conditions come from? They arise because Yun and Si Tian are not in accord. When Yun matches the transformation of Si Tian, their names follow the laws of addition and subtraction.
The method calculates four years as one Ji (cycle); when the year encounters a San He (Three Harmony) combination, the cycle restarts. Shen-Zi-Chen years are the First Six Heavens, starting from Yin, Zi, Hai, You, Shen, Wu. Si-You-Chou years are the Second Six Heavens, starting from Si (Snake), Mao (Rabbit), Yin (Tiger), Zi (Rat), Hai (Pig), You (Rooster). Yin-Wu-Xu years are the Third Six Heavens, starting from Shen, Wu, Si, Mao, Yin, Zi. Hai-Mao-Wei years are the Fourth Six Heavens, determining entry into Bu time (afternoon), Zao time (morning), and Yu time (mid-morning) for exit. Each Qi phase lasts sixty days before changing, often leaving a remainder of eighty-seven and a half Ke (time units). When the 3rd and 5th phases wish to transition, calculate from the first Ke based on the date. When the 2nd, 4th, and 6th phases wish to transition, judge according to the Shen Ding Ke at that time. Twenty-four steps circulate through one hundred Ke to form one degree, moving like a string of fish. The first thirty days are called "Chu" (Beginning); during this time, Heaven's Qi is active, and Earth's Qi is latent. The latter thirty days are called "Zhong" (Middle); during this time, Earth's Qi is active, and Heaven's Qi follows. When Heaven's Qi is in charge, Earth's Qi rises; when Earth's Qi is in charge, Heaven's Qi descends. When Earth's Qi rises, it enters Tai Xu (the Great Void); when Heaven's Qi descends, it enters You Zhi (substantial matter). Rising leads to descending, and descending leads to rising; mutual causation of rise and fall produces change. Whenever discussing Heaven, seek its root: Wind, Summer Heat, Fire, Dampness, Dryness, and Cold adhere to Heaven. Whenever discussing Earth, seek its position: Two Fires, Wood, Earth, Metal, and Water are discussed regarding Earth. Whenever discussing Humanity, seek the Qi Intersection (Qi Jiao); there are often differences in boundaries. If Heaven's Qi is insufficient, Earth's Qi follows to supplement; if Earth's Qi is insufficient, Heaven's Qi comes to assist. Yun resides in the middle and often responds first. Return to what is harmonious and similar; dislike what cannot withstand. Superiority above causes Heaven's Qi to descend downward; superiority below causes Earth's Qi to migrate upward. Minor cases show slight improvement, severe cases show significant deterioration. Auxiliary treatments can easily alter the condition; observe the disease state.