人禀父母精血化生。故内经有曰。阳施阴化。谓之有子。圣济经言。方其受授之初。一月血凝。二月胚胎兆。三月
阳神为魂。四月阴灵为魄。五月五行分五脏。六月六律定六腑。七月七精开窍。八月八景具全。九月气足象成。十月百
神集备。至日满而生也。（又云。一月如珠露。二月若桃花。三月形象成。四月男女分。五月腑脏具。六月筋骨全。七月
魂生而动左。八月魄长而动右。九月三转身。十月足而生。此未知其所出。）其始有谓之妊者。以其阳始而阴任之也。有
谓之胚者。以其未成为器而犹坯也。有谓之胞者。以其已为正阳而阴
包之也。有谓之胎者。以食于母而为口颐也。有谓之娠者。以其有时而动也。有谓之怀者。以其有身而根据也。原夫此象
者。皆阳始阴任在有形之先。次由五行而后化成也。故曰。阴阳具而五行立矣。且阴之所任者。
壬也。一阳壬兆。则人乃肇生。命门主生气之原。精所藏焉。壬、阳水也。合丁之阴火而生丙。故有命门。然后生心。
心主血。神所藏焉。丙之阳火。合辛之阴金而生庚。故有心然后有肺。肺主皮毛。魄所藏焉。庚、阳金也。合乙之阴木
而生甲。故有肺然后生肝。肝主筋。魂所藏焉。甲为阳木。合己之阴土而生戊。故有肝然后生脾。脾生肉。意所藏焉。
戊为阳土。合癸之阴水而生壬。故有脾然后生肾。肾主骨。志所藏焉。故肾与命门一也。此阴阳五行。夫妇生化。自然
之理也。人之赋禀。自受气至胎化。自成形至生养。亦皆由焉。
Human beings are generated from the transformation of their parents' essence and blood. Therefore, the *Huangdi Neijing* (Yellow Emperor's Inner Canon) states: "Yang exerts influence and Yin transforms; this is called having offspring." The *Shengji Jing* (Classic of Holy Relief) records: At the initial moment of conception, in the first month, blood coagulates; in the second month, the embryo begins to take shape; in the third month, the Yang spirit becomes the Hun (ethereal soul); in the fourth month, the Yin spirit becomes the Po (corporeal soul); in the fifth month, the Five Elements differentiate into the Zang organs; in the sixth month, the Six Harmonies determine the Fu organs; in the seventh month, the seven orifices open; in the eighth month, the eight faculties are complete; in the ninth month, Qi is sufficient and the form is established; in the tenth month, all divine functions are gathered and prepared, leading to birth upon completion of the term. (Another account says: In the first month, it is like a drop of dew; in the second, like a peach blossom; in the third, the image forms; in the fourth, male and female are distinguished; in the fifth, viscera and bowels are equipped; in the sixth, sinews and bones are whole; in the seventh, the Hun arises and movement is to the left; in the eighth, the Po grows and movement is to the right; in the ninth, the fetus turns three times; in the tenth, it is born fully formed. It is unknown where this account originates.)
Initially, it is called "Ren" (pregnancy) because Yang begins and Yin bears it. It is called "Pei" (embryo) because it has not yet formed distinct organs and remains like an unfired clay brick. It is called "Bao" (womb/uterus) because it has acquired true Yang energy and is wrapped by Yin. It is called "Tai" (fetus) because it receives nourishment from the mother to sustain the mouth and chin. It is called "Shen" (gestation) because there is occasional movement. It is called "Huai" (carrying) because the body is pregnant and supported. Tracing back to the origin of these terms, they all refer to the state before physical form exists, where Yang initiates and Yin supports, followed by transformation through the Five Elements. Thus it is said: When Yin and Yang are complete, the Five Elements are established.
Regarding what Yin bears, it is Ren Water. When one Yang appears in Ren, human life begins. the Mingmen (Gate of Life) governs the source of vital Qi, where essence is stored. Ren is Yang Water; combining with Ding Yin Fire, it generates Bing Fire. Thus, after the Mingmen, the Heart is generated. The Heart governs blood, and Shen (spirit) is stored within it. Bing is Yang Fire; combining with Xin Yin Metal, it generates Geng Metal. Thus, after the Heart, the Lung is generated. The Lung governs skin and hair, and Po is stored within it. Geng is Yang Metal; combining with Yi Yin Wood, it generates Jia Wood. Thus, after the Lung, the Liver is generated. The Liver governs sinews, and Hun is stored within it. Jia is Yang Wood; combining with Ji Yin Earth, it generates Wu Earth. Thus, after the Liver, the Spleen is generated. The Spleen produces flesh, and Yi (intention) is stored within it. Wu is Yang Earth; combining with Gui Yin Water, it generates Ren Water. Thus, after the Spleen, the Kidney is generated. The Kidney governs bones, and Zhi (will) is stored within it. Therefore, the Kidney and the Mingmen are essentially one. This is the natural principle of Yin-Yang and the Five Elements, and the generation and transformation of husband and wife. Human endowment, from receiving Qi to fetal transformation, from forming shape to postnatal nurturing, all follows this law.