《灵枢·九宫八风篇》曰∶太乙常以冬至之日，居叶蛰之宫四十六日，明日居天留四十六日，明日居仓门
四十六日，明日居阴洛四十五日，明日居天宫四十六日，明日居玄委四十六日，明日居仓果四十六日，明日
居新洛四十五日，明日复居叶蛰之宫，曰冬至矣。太乙日游，以冬至之日，居叶蛰之宫，数所在，日从一处，
至九日，复反于一，常如是无已，终而复始。太乙移日，天必应之以风雨，以其日风雨则吉，岁美，民安，
少病矣，先之则多雨，后之则多汗。太乙在冬至之日有变，占在君；太乙在春分之日有变，占在相；太乙在中
宫之日有变，占在吏；太乙在秋分之日有变，占在将；太乙在夏至之日有变，占在百姓。所谓有变者，太
乙居五宫之日，病风折树木，扬沙石。各以其所主占贵贱，因视风所从来而占之。风从其所居之乡来者为实
风，主生，长养万物；从其冲后来者为虚风，伤人者也，主杀主害。谨候虚风而避之，故圣人日避虚邪，如
避矢石，邪勿能害，此之谓也。
太乙者，太岁之神也，有行住之分。自冬至日住居坎宫；次日游行艮宫，由震而巽；至第五日，游于中宫；
第六日，游于离宫，由坤而兑；至第九日，游于干宫，为一周，第十日仍居坎宫。次日又游艮宫，如是周而复
始，至立春日，太乙迁居艮宫，次日游于震宫，由巽而离；至第五日，游于中宫；第六日，游于坤宫，由兑而
干；至第九日，游于坎宫，为一周，第十日仍居艮宫。次日又照前游历。如是循节气迁居，逐日游历，至迁居
干宫，已周一岁，乃至冬至之日，即次年之太岁神居坎官也。挨查节气日期，观太岁神所居之宫，占风雨寒热
之气，以验吉凶，如经文所云者是也。假如太乙居坎宫之日，以离、坤、兑、干为后，以中央、巽、震、艮为
前；太乙居中宫之日，以坎、艮、震、巽为后，离、坤、兑、干为前；太乙居离宫之日，以中央、干、兑、坤
为前，巽、震、艮、坎为后，余可类推矣。其从前来者为实风，从所居之乡来者为正风，从后来者为虚风贼邪，
主杀害，故圣人避之，如避矢石。
是故太乙徙立于中宫，乃朝八风，以占吉凶也。风从南方来，名曰大弱风，其伤人也，内舍于心，外在于
脉，气主热；风从西南方来，名曰谋风，其伤人也，内舍于脾，外在于肌，其气主为弱；风从西方来，名曰刚
风，其伤人也，内舍于肺，外在于皮肤，其气主为燥；风从西北方来，名曰折风，其伤人也，内舍于小肠，外
在于手太阳脉，脉绝则溢，脉闭则结不通，善暴死；风从北方来，名曰大刚风，其伤人也，内舍于肾，外在于
骨，与肩背之膂筋，其气主为寒也；风从东北方来，名曰凶风，其伤人也，内舍于大肠，外在于两胁腋骨，下
及肢节；风从东方来，名曰婴儿风，其伤人也，内舍于肝，外在于筋纽，其气主为身湿；风从东南方来，名曰
弱风，其伤人也，内舍于胃，外在肌肉，其气主体重。此八风皆从其虚之乡来，乃能病患。三虚相搏，则为暴
病卒死。两实一虚，病则为淋露寒热。犯其雨湿之地，则为痿。故圣人避风，如避矢石焉。其有三虚，而偏中
于邪风，则为击仆偏枯矣。
此又申明太乙居中宫之日，而辨八风为病之理也。风由八卦方位而来，故其伤人脏腑，亦按八卦方位以应
之，而八卦具五行之气，即气变化而成其病也，然皆论其常理耳。凡经论阴阳、五行、八卦之道，皆是活法，
变化无穷，要必明其圆通至理，方能头头是道，如或拘泥穿凿，即有不能融贯者矣。其从后来之虚风，伤人为
甚，若又逢月廓虚，人身虚，是谓三虚会合，则暴病卒死。或两实一虚，两虚一实，其病有轻重不等，未至卒
死。其三虚会合，或不卒死，而偏中其邪，则必跌仆而成偏枯半身不遂之病。故圣人避虚风，如避矢石焉。
《灵枢·九宫八风篇》说：太乙神通常在冬至这一天，居住在叶蛰宫四十六天，第二天居住在天留宫四十六天，第三天居住在仓门宫四十六天，第四天居住在阴洛宫四十五天，第五天居住在天宫四十六天，第六天居住在玄委宫四十六天，第七天居住在仓果宫四十六天，第八天居住在新洛宫四十五天，第九天又回到叶蛰宫，这标志着又一个冬至的到来。太乙神每日的行程是：在冬至这一天，它居住在叶蛰宫，按照这个顺序，从一处走到第九处，再返回第一处，总是这样循环往复，终而复始。
当太乙神移动位置时，天气必定以风雨来响应。如果在那一天刮风下雨，就是吉兆，预示这一年庄稼丰收，百姓安康，生病的人少；如果风雨提前到来，则多雨；如果风雨推迟到来，则多干旱（汗指干旱）。太乙神在冬至之日若有异常变化，占卜结果应验在君主身上；在春分之日有变，应验在宰相身上；在中宫之日有变，应验在官吏身上；在秋分之日有变，应验在将领身上；在夏至之日有变，应验在百姓身上。所谓“有变”，是指太乙神居住在某宫位的日子，出现大风折断树木、扬起沙石的现象。分别根据其所主方位来占测贵贱祸福，并观察风来的方向进行占断。
风从太乙神所居之乡吹来的，称为实风，主生长，滋养万物；从对冲方向后面吹来的，称为虚风，是伤人的邪气，主杀戮和危害。谨慎地守候并避开虚风，所以圣人说要躲避虚邪之气，就像躲避箭矢石头一样，邪气就不能伤害人，说的就是这个道理。
太乙，就是太岁之神，有停留和行走的区别。从冬至日开始，太乙神停留在坎宫；第二天行走在艮宫，接着经过震宫到巽宫；到第五天，游历于中宫；第六天，游历于离宫，接着经过坤宫到兑宫；到第九天，游历于干宫，完成一周；第十天仍然居住在坎宫。第二天又游历艮宫，如此周而复始。到了立春日，太乙神迁居到艮宫，第二天游历于震宫，经过巽宫到离宫；到第五天，游历于中宫；第六天，游历于坤宫，经过兑宫到干宫；到第九天，游历于坎宫，完成一周；第十天仍然居住在艮宫。第二天又照之前的路线游历。如此随着节气变迁居所，逐日游历，直到迁居到干宫，已经过完一年，又到了冬至之日，即次年的太岁神居住在坎宫。挨个查询节气日期，观察太岁神所居住的宫位，占测风雨寒热之气，以此验证吉凶，正如经文所说的那样。
假如太乙神居住在坎宫的日子，以离、坤、兑、干为后方，以中央、巽、震、艮为前方；太乙神居住在中宫的日子，以坎、艮、震、巽为后方，离、坤、兑、干为前方；太乙神居住在离宫的日子，以中央、干、兑、坤为前方，巽、震、艮、坎为后方，其余情况可以类推。那些从前方吹来的风是实风，从太乙神所居之乡吹来的是正风，从后方吹来的是虚风贼邪，主杀害，所以圣人躲避它们，就像躲避箭矢石头一样。
因此，太乙神迁移站立在中宫，于是朝见八方之风，以此来占测吉凶。风从南方来，名叫大弱风，它伤人时，内舍于心，外在表现为脉，其气主热；风从西南方来，名叫谋风，它伤人时，内舍于脾，外在表现为肌，其气主弱；风从西方来，名叫刚风，它伤人时，内舍于肺，外在表现为皮肤，其气主燥；风从西北方来，名叫折风，它伤人时，内舍于小肠，外在表现为手太阳脉，脉气绝则外溢，脉气闭则结塞不通，容易突然死亡；风从北方来，名叫大刚风，它伤人时，内舍于肾，外在表现为骨，以及肩背的膂筋，其气主寒；风从东北方来，名叫凶风，它伤人时，内舍于大肠，外在表现为两胁腋骨，下及四肢关节；风从东方来，名叫婴儿风，它伤人时，内舍于肝，外在表现为筋纽，其气主身湿；风从东南方来，名叫弱风，它伤人时，内舍于胃，外在表现为肌肉，其气主体重。这八种风都是从空虚的方向吹来的，才能使人患病。三种“虚”相搏结，就会发生暴病猝死。两种“实”一种“虚”，疾病表现为淋露或寒热交替。触犯潮湿之地，就会发生痿证。所以圣人避风，就像躲避箭矢石头一样。如果有三种“虚”同时存在，且偏中于邪风，就会导致击仆或偏枯（半身不遂）。
这段文字又申明了太乙神居中宫之日，辨别八风致病的原理。风由八卦方位而来，所以它伤害脏腑，也按八卦方位相应，而八卦具备五行之气，即是气的变化形成了疾病，但这都是论述常理。凡是经典论述阴阳、五行、八卦的道理，都是灵活的方法，变化无穷，一定要明白其圆通至理，才能条理清晰；如果拘泥穿凿，就不能融会贯通了。那从后方吹来的虚风，伤人最为严重，如果再遇到月廓空虚（农历月末）、人身虚弱，这就叫三虚会合，就会暴病猝死。或者是两实一虚，两虚一实，病情有轻重不等，不至于猝死。其三虚会合，或者没有猝死，而是偏中邪气，就必然跌倒仆倒，形成偏枯半身不遂的病。所以圣人躲避虚风，就像躲避箭矢石头一样。
*Ling Shu (Spiritual Pivot) · Jiu Gong Ba Feng Chapter* states: Tai Yi (Taiyi, the deity of the annual cycle) usually resides in Ye Zhe Palace (Leaf Stagnation Palace) for forty-six days starting from the Winter Solstice. The next day, it resides in Tian Liu Palace (Heavenly Retention Palace) for forty-six days; the following day, in Cang Men Palace (Granary Gate Palace) for forty-six days; the next day, in Yin Luo Palace (Yin Luo Palace) for forty-five days; the next day, in Tian Gong Palace (Heavenly Palace) for forty-six days; the next day, in Xuan Wei Palace (Mysterious Submission Palace) for forty-six days; the next day, in Cang Guo Palace (Granary Fruit Palace) for forty-six days; the next day, in Xin Luo Palace (New Luo Palace) for forty-five days; and on the ninth day, it returns to Ye Zhe Palace, marking another Winter Solstice.
The daily journey of Tai Yi is as follows: On the day of the Winter Solstice, it resides in Ye Zhe Palace. Counting from one location to nine, it then returns to the first, always continuing in this manner, ending and beginning anew. When Tai Yi shifts its position, heaven must respond with wind and rain. If there is wind and rain on that day, it is auspicious, indicating a good harvest, peace among the people, and fewer illnesses. If the wind and rain come early, there will be excessive rain; if they come late, there will be excessive drought.
If there is an anomaly when Tai Yi is present on the day of the Winter Solstice, the omen applies to the ruler; if on the day of the Spring Equinox, it applies to the chancellor; if on the day of the Central Palace, it applies to officials; if on the day of the Autumn Equinox, it applies to generals; and if on the day of the Summer Solstice, it applies to the common people. By "anomaly," it means that on the days Tai Yi resides in the five palaces, strong winds break trees and scatter sand and stones. One should predict nobility or baseness based on what each palace governs, and observe the direction from which the wind comes to make divinations.
Wind coming from the direction where Tai Yi resides is called *Shi Feng* (Solid Wind), which promotes growth and nourishes all things. Wind coming from the opposite direction behind Tai Yi is called *Xu Feng* (Empty Wind), which harms people, promoting killing and harm. Carefully monitoring and avoiding Xu Feng, the sages said to avoid *Xu Xie* (Empty Evils), just as one avoids arrows and stones, so that evil cannot harm. This is what is meant.
Tai Yi is the spirit of Tai Sui (Grand Duke Jupiter), having distinctions between staying and moving. Starting from the Winter Solstice, it stays in Kan Palace (Water Palace); the next day, it moves through Gen Palace (Mountain Palace), passing through Zhen Palace (Thunder Palace) to Xun Palace (Wind Palace); on the fifth day, it tours the Central Palace; on the sixth day, it tours Li Palace (Fire Palace), passing through Kun Palace (Earth Palace) to Dui Palace (Lake Palace); on the ninth day, it tours Qian Palace (Heaven Palace), completing one cycle; on the tenth day, it remains in Kan Palace. The next day, it again tours Gen Palace, cycling endlessly. Upon the Start of Spring, Tai Yi relocates to Gen Palace, the next day tours Zhen Palace, passing through Xun Palace to Li Palace; on the fifth day, it tours the Central Palace; on the sixth day, it tours Kun Palace, passing through Dui Palace to Qian Palace; on the ninth day, it tours Kan Palace, completing one cycle; on the tenth day, it remains in Gen Palace. The next day, it continues touring as before. Thus, following the solar terms to relocate and touring daily, until it relocates to Qian Palace, a full year has passed, reaching the Winter Solstice again, at which point the Tai Sui Spirit of the next year resides in Kan Palace. By checking the dates of solar terms and observing the palace where the Tai Sui Spirit resides, one can divine the qi of wind, rain, cold, and heat to verify auspiciousness or inauspiciousness, as stated in the classic text.
For example, when Tai Yi resides in Kan Palace, Li, Kun, Dui, and Qian are considered the rear, while the Center, Xun, Zhen, and Gen are the front; when Tai Yi resides in the Central Palace, Kan, Gen, Zhen, and Xun are the rear, while Li, Kun, Dui, and Qian are the front; when Tai Yi resides in Li Palace, the Center, Qian, Dui, and Kun are the front, while Xun, Zhen, Gen, and Kan are the rear. The rest can be deduced similarly. Winds coming from the front are *Shi Feng* (Solid Wind); winds coming from the direction where Tai Yi resides are *Zheng Feng* (Proper Wind); winds coming from the rear are *Xu Feng* (Empty Wind) and *Ze Xie* (Thieving Evil), which cause harm and death. Therefore, the sages avoid them as they would avoid arrows and stones.
Thus, when Tai Yi moves to stand in the Central Palace, it faces the Eight Winds to divine auspiciousness and inauspiciousness. Wind coming from the south is named *Da Ruo Feng* (Great Weak Wind). When it injures people, it internally settles in the Heart and externally affects the vessels, with its qi being hot. Wind coming from the southwest is named *Mou Feng* (Stratagem Wind). When it injures people, it internally settles in the Spleen and externally affects the muscles, with its qi being weak. Wind coming from the west is named *Gang Feng* (Rigid Wind). When it injures people, it internally settles in the Lungs and externally affects the skin, with its qi being dry. Wind coming from the northwest is named *Zhe Feng* (Breaking Wind). When it injures people, it internally settles in the Small Intestine and externally affects the Hand Taiyang Vessel. If the vessel qi is exhausted, it overflows; if blocked, it becomes obstructed, leading to sudden death. Wind coming from the north is named *Da Gang Feng* (Great Rigid Wind). When it injures people, it internally settles in the Kidneys and externally affects the bones and the *Lv Jin* (back muscles) of the shoulders and back, with its qi being cold. Wind coming from the northeast is named *Xiong Feng* (Auspicious/Fierce Wind - contextually fierce here). When it injures people, it internally settles in the Large Intestine and externally affects the bilateral hypochondriac axillary bones and down to the limb joints. Wind coming from the east is named *Ying Er Feng* (Infant Wind). When it injures people, it internally settles in the Liver and externally affects the tendon connections, with its qi causing bodily dampness. Wind coming from the southeast is named *Ruo Feng* (Weak Wind). When it injures people, it internally settles in the Stomach and externally affects the muscles, with its qi causing heaviness. These eight winds can only cause disease when they come from empty directions. When three types of "deficiency" combine, sudden illness and death occur. With two solidities and one deficiency, the disease manifests as strangury, emaciation, or alternating chills and fever. Treading on wet ground causes *Wei* syndrome (flaccidity). Therefore, the sages avoid wind as they would avoid arrows and stones. If there are three deficiencies and one is partially struck by evil wind, it results in falling/collapsing or hemiplegia.
This section further clarifies the principle of distinguishing diseases caused by the Eight Winds on the day Tai Yi resides in the Central Palace. Since wind comes from the Bagua (Eight Trigrams) directions, the organs and viscera it injures also correspond to these directions. As the Bagua possess Five Element qi, changes in qi form diseases. However, this discusses general principles. All classics discussing Yin-Yang, Five Elements, and Bagua employ flexible methods with infinite variations. One must understand their comprehensive and profound logic to apply them correctly; otherwise, rigid interpretation leads to confusion. The *Xu Feng* (Empty Wind) coming from the rear harms people severely. If accompanied by a hollow moon phase and human physical deficiency, this is called the convergence of three deficiencies, leading to sudden illness and death. If there are two solidities and one deficiency, or two deficiencies and one solidity, the disease severity varies but does not necessarily lead to sudden death. If the three deficiencies converge without causing sudden death, but evil wind strikes partially, it inevitably leads to falling and hemiplegia. Therefore, the sages avoid *Xu Feng* as they would avoid arrows and stones.