天地者，形之大也；阴阳者，气之大也。惟形与气相资而立，未始偏废。（《庄子·则
阳篇》太公调曰∶天地者，形之大者也；阴阳者，气之大者也。道者为之公，气以形载，形
以气充。惟气与形两者相待，故曰相资而立，未始偏废）。男女构精，万物化生，天地阴阳
之形气寓焉。（《系辞》曰∶天地 ，万物化醇；男女构精，万物化生）。语七八之数。七，
少阳也；八，少阴也，相感而流通。故女子二七天癸至；男子二八天癸至，则以阴阳交合而
兆始故也。（岐伯曰∶女子二七而天癸至，任脉通，冲脉盛，月事以时下，故有子。丈夫二
八肾气盛，天癸至，精气溢泻，阴阳和，故能有子。传曰∶女子十四有为人母之道，四十九
绝生育之理；男子十六有为人父之道，六十四绝阳化之理）。语九十之数。九，老阳也；十
，老阴也。相包而赋形。故阴穷于十，男能围之；阳穷于九，女能方之。则以阴阳相生而成
终故也（《字说》∶阴穷于十，围之者男；阳穷于九，方之者女。九有变也，女方之不足；
十无变也，男足以围之。解曰∶男有家，所从围阴于外；女有室，所以方阳于内。《易》曰
∶妇人正吉，从一而终也。夫子制仪，从妇凶也，围圆也，君道也，夫道也。圆则可以制仪
而行仁。方也，臣道也，妇道也。方则从一而已。男从围与规，从夫同意；女从仁与臣，从
仁同意）。元气孕毓，皆始于子。自子推之，男左旋，积岁三十而至巳；女右旋，积岁二十
而至巳。巳为正阳，阴实从之。自巳怀妊，男左旋，十月而生于寅；女右旋，十月而生于申
。申为三阴，寅为三阳，而生育之时着矣。其禀赋也！体有刚柔，脉有强弱，气有多寡，血
有盛衰，皆一定而不易也。（《十九难》曰∶男生于寅，寅为木，阳也；女子生于申，申为
金，阴也。杨氏注云∶元气起于子，人之所生也。男从子，左行三十；女从子，右行二十，
俱至于巳，为夫妇怀妊也。古者男子三十、女年二十，然后行嫁娶，法于此也。十月而生男
从巳左行，至寅为十月，故男行年起于丙寅。女从巳右行，至申为十月，故女行年起于壬申。
）以至分野异域，则所产有多寡之宜，吉事有祥，则所梦各应其类。是故荆扬薄壤多女，雍
冀浓壤多男。熊罴为男子之祥，蛇虺为女子之祥，是皆理之可推也（周官职方氏，扬州其民
，二男五女；荆州其民，一男二女；壅州其民，三男二女；冀州其民，五男三女。《诗斯干
篇》名吉梦维何？维熊维罴，维虺维蛇，大人占之。维熊维罴，男子之祥，维虺维蛇，女子
之祥。）胎化之法，有所谓转女为男者，亦皆理之自然。如食牡鸡，取阳精之全于天产者；
带雄黄，取阳精之全于地产者。（《千金方》转女为男，丹参丸。用东门上雄鸡头。又方取
雄黄一两，缝囊盛带之。《本草》∶丹雄鸡补虚温中，通神杀毒；其肝补肾；其冠血益阳。
雄黄人佩之，鬼神不能近，毒物不能伤。）操弓矢，藉斧斤，取刚物之见于人事者，气类潜
通，造化密移，必于三月兆形之先。盖方仪则未具，阳可以胜阴，变女为男，理固然也（巢
氏论云∶妊娠三月，始胎形，象始化，未有定仪，见物而变。欲得男者，操弓夭，射雄鸡。）
天地，是形体中最大的存在；阴阳，是气中最大的存在。只有形体与气相互依赖才能确立，从未有过偏废的情况。（《庄子·则阳篇》太公调说：天地，是形体中最大的；阴阳，是气中最大的。道作为它们的共同本源，气依托形体而承载，形体依靠气来充实。只有气与形两者相互等待、依存，所以说是相互依赖而确立，从未偏废）。男女交合精气，万物由此化生，天地的阴阳形体与气便蕴含其中。（《系辞》说：天地交感，万物化育醇厚；男女交合精气，万物由此化生）。谈及“七八”之数。七，是少阳；八，是少阴，二者相互感应而流通。所以女子十四岁时天癸（指促进生殖机能成熟的物质）至；男子十六岁天癸至，这是因为阴阳交合而孕育生命起始的缘故。（岐伯说：女子十四岁天癸至，任脉通畅，冲脉旺盛，月经按时来潮，所以能生育。男子十六岁肾气盛，天癸至，精气满溢外泄，阴阳调和，所以能有子。传文说：女子十四岁具备做母亲的条件，四十九岁断绝生育的道理；男子十六岁具备做父亲的条件，六十四岁断绝阳气化的道理）。谈及“九十”之数。九，是老阳；十，是老阴。二者相互包容而赋予形体。所以阴数穷尽于十，男性能包围它；阳数穷尽于九，女性能方正它。这是因为阴阳相生而成终的缘故（《字说》：阴穷尽于十，包围它的是男性；阳穷尽于九，使其方正的是女性。九有变化，女性使其方正尚显不足；十无变化，男性足以包围它。解释：男性有家室，从外部包围阴；女性有内室，从内部方正阳。《易经》说：妇人守正吉祥，从一而终。夫子制定礼仪，顺从妇女则凶。圆，象征包围，代表君道、夫道。圆则可以制定礼仪并施行仁爱。方，象征臣道、妇道。方则从一而已。男性遵循包围与规整，与“夫”字同义；女性遵循仁爱与臣服，与“仁”字同义）。元气孕育胎儿，都始于子时。从子时推算，男性向左旋转，积累三十年到达巳时；女性向右旋转，积累二十年到达巳时。巳时为正阳，阴实依附于它。从巳时开始怀孕，男性向左旋转，十月后生于寅时；女性向右旋转，十月后生于申时。申时为三阴，寅时为三阳，生育的时机便显现出来了。其禀赋差异！身体有刚柔之分，脉象有强弱之别，气有多寡之差，血有盛衰之异，这些都是固定不变且不可改变的。（《难经·第十九难》说：男性生于寅，寅属木，为阳；女性生于申，申属金，为阴。杨氏注释说：元气起于子，这是人出生的根本。男性从子位向左运行三十年；女性从子位向右运行二十年，都到达巳位，此时结为夫妇并怀孕。古时候男子三十岁、女子二十岁才进行嫁娶，就是效法这一规律。十月后生下男孩，从巳位左行到寅位为十月，所以男性行年起于丙寅。女性从巳位右行到申位为十月，所以女性行年起于壬申。）至于不同地域分野，所产男女数量各有适宜，吉祥之事有征兆，所梦各异且对应相应类别。因此荆州、扬州土地薄多生女儿，雍州、冀州土地肥沃多生儿子。熊罴是男子的吉兆，蛇虺是女子的吉兆，这都是道理可以推知的（《周礼·职方氏》记载：扬州的百姓，二男五女；荆州的百姓，一男二女；雍州的百姓，三男二女；冀州的百姓，五男三女。《诗经·斯干篇》问：吉利的大梦是什么？梦见熊和罴，梦见虺和蛇，大人占卜说：梦见熊和罴，是男子的吉兆；梦见虺和蛇，是女子的吉兆。）胎化之法中，有所谓“转女为男”的方法，也都是自然之理。如食用公鸡，取自然界动物中完整的阳精；佩戴雄黄，取大地出产中完整的阳精。（《千金方》中转女为男的法子，用丹参丸。使用东门上公鸡的头。另一法取雄黄一两，缝成囊袋佩戴在身上。《本草》记载：丹雄鸡补虚温中，通神杀毒；其肝补肾；其冠血益阳。人们佩戴雄黄，鬼神不能靠近，毒物不能伤害。）操持弓箭，借助斧头，取人事中刚硬之物，气类暗中相通，造化秘密转移，必定在三个月胎儿成形之前。因为此时胎儿仪态尚未具备，阳可以胜阴，将女转为男，道理本来就是如此（巢元方论述说：妊娠三月，开始胎形，形象开始变化，还没有固定的形态，见到什么就变成什么。想要生男孩的，操持弓箭，射杀雄鸡。）
Heaven and Earth are the greatest of forms; Yin and Yang are the greatest of Qi (vital energy). Only when form and Qi mutually support each other can they be established, never being neglected or abandoned. (Tai Gong Diao in *Zhuangzi: Ze Yang* said: Heaven and Earth are the greatest of forms; Yin and Yang are the greatest of Qi. The Dao serves as their common source. Qi is carried by form, and form is filled by Qi. Since Qi and form wait for and depend on each other, it is said that they are established through mutual support, never being neglected.) When male and female combine their essence, all things are transformed and born, containing the form and Qi of Heaven and Earth's Yin and Yang. (*Xici* states: Heaven and Earth interact, causing all things to mature richly; male and female combine essence, causing all things to be born.) Regarding the numbers seven and eight: Seven is Shaoyang (Lesser Yang); Eight is Shao Yin (Lesser Yin), interacting and flowing. Thus, at fourteen years old (2x7), Tian Gui (substance promoting reproductive maturity) arrives in women; at sixteen years old (2x8), Tian Gui arrives in men, marking the beginning of conception due to the union of Yin and Yang. (Qibo stated: At fourteen, a woman's Tian Gui arrives, her Ren Mai (Conception Vessel) becomes unobstructed, and Chong Mai (Penetrating Vessel) flourishes, allowing menstruation to occur regularly and enabling pregnancy. At sixteen, a man's Kidney Qi flourishes, his Tian Gui arrives, essence overflows, Yin and Yang harmonize, enabling him to have children. Texts state: A woman has the capacity for motherhood at fourteen and ceases reproductive function at forty-nine; a man has the capacity for fatherhood at sixteen and ceases Yang transformation at sixty-four.) Regarding the numbers nine and ten: Nine is Laoyang (Old Yang); Ten is Lao Yin (Old Yin), enveloping each other to bestow form. Thus, Yin reaches its limit at ten, which men can encircle; Yang reaches its limit at nine, which women can square. This is because Yin and Yang generate each other to complete the cycle. (*Zishuo*: Yin limits at ten, encircled by men; Yang limits at nine, squared by women. Nine involves change, so women squaring it is insufficient; Ten involves no change, so men enclosing it is sufficient. Explanation: Men have households, enclosing Yin externally; Women have chambers, squaring Yang internally. *I Ching* says: A woman remains correct and auspicious by following one until the end. The Master regulates rituals; following women brings misfortune. Roundness symbolizes enclosure, representing the Way of the Ruler and the Way of the Husband. Roundness allows for regulating rituals and practicing benevolence. Squareness represents the Way of the Minister and the Way of the Wife. Squareness implies following one path exclusively. Men follow enclosure and regulation, consistent with "Husband"; Women follow benevolence and submission, consistent with "Ren" (Benevolence)). Yuan Qi (Primordial Qi) nurturing the fetus begins at Zi (Rat hour/position). Counting from Zi, men rotate left for thirty years reaching Si (Snake position); women rotate right for twenty years reaching Si. Si is Zheng Yang (True Yang), where Yin solidifies and follows. From Si during pregnancy, men rotate left, born after ten months at Yin (Tiger position); women rotate right, born after ten months at Shen (Monkey position). Shen is Sanyin (Three Yin), Yin is Sanyang (Three Yang), revealing the timing of reproduction. Their innate endowments vary! Bodies differ in rigidity and flexibility, pulses in strength and weakness, Qi in abundance and scarcity, Blood in flourishing and decline, all fixed and unchangeable. (*Nanjing Chapter 19* states: Men are born at Yin, Yin belongs to Wood, which is Yang; Women are born at Shen, Shen belongs to Metal, which is Yin. Yang's commentary notes: Yuan Qi originates at Zi, the root of human life. Men move left from Zi for thirty years; women move right from Zi for twenty years, both reaching Si for marriage and pregnancy. In ancient times, men married at thirty and women at twenty, following this law. Ten months after Si, boys are born moving left to Yin, so men's age cycles start at Bingyin. Girls move right from Si to Shen for ten months, so women's age cycles start at Renshen.) As for different regions, the proportion of births varies appropriately; auspicious events bring omens, and dreams correspond to categories. Thus, Jingzhou and Yangzhou with thin soil produce more daughters; Yongzhou and Jizhou with fertile soil produce more sons. Bears and black bears are omens for boys, vipers and snakes are omens for girls, all deducible by reason. (*Zhou Li - Zhifang Shi*: People of Yangzhou: two men, five women; Jingzhou: one man, two women; Yongzhou: three men, two women; Jizhou: five men, three women. *Shi Jing - Si Gan*: What are auspicious dreams? Dreams of bears and black bears, vipers and snakes. The elder divines: Bears and black bears are omens for boys; vipers and snakes are omens for girls.) Among fetal transformation methods, there is "turning a female fetus into a male," also natural law. For example, eating rooster meat takes the complete Yang essence from animal products; wearing Realgar takes the complete Yang essence from mineral products. (*Qianjin Fang* method for turning female to male uses Danshen Wan, utilizing the head of a rooster from the east gate. Another method uses one liang of Realgar sewn into a pouch to wear. *Bencao*: Dan Xiong Ji (Red Rooster) tonifies deficiency and warms the middle, unblocks spirit and detoxifies; its liver tonifies Kidneys; its comb blood benefits Yang. Wearing Realgar keeps ghosts and demons away and prevents injury from toxic creatures.) Holding bows and arrows, wielding axes, utilizes rigid objects in human affairs. Qi types connect secretly, Creation shifts subtly, definitely before the third month when the fetus takes shape. Because the fetal form is not yet established, Yang can overcome Yin, changing female to male, which is naturally so. (Chao Yuanfang discussed: In the third month of pregnancy, the fetal form begins, shapes begin to transform, lacking fixed appearance, changing upon seeing things. To desire a boy, hold bows and arrows, shoot roosters.)