答曰。男子以精为本。女子以血为源。男子为阳。阳中必有阴。阴中之数八。故一八而阳精
降。二八而阳精溢。女子为阴。阴中必有阳。阳中之数七。故一七而阴血升。二七而阴血溢
。阳精阴血。皆饮食五味之实秀。为男女之本源也。方其升也。智虑开明。齿牙更始。发黄
者黑。筋弱者强。暨其溢也。凡充身肢体。手足耳目之余。虽针芥之处。无有不至。凡子形
肖父母者。盖其精血。尝于父母之身。无所不历也。是以父一肢废。则子一肢不肖其父母
。一目亏。则子一目不肖其父母。然雌鸡牝兽。无天癸而成胎。何也。鸟兽精血往来尾间也
。精未通而遇女子通其精。则五体有不满之处。异日有难状之疾。阴已痿而思色以降其精。
则精不出而内败。小便道涩而为淋。精已耗而复竭也。女人天癸既至。逾十年无男子合。则
不调。未逾十年男子合。亦不调。不调则旧血不出。新血误行。或渍而入骨。或变而为肿。
或虽合而难子。合男子多。则沥枯虚人。产乳众。则血枯杀人。观其精血。思过半矣。
答曰。天以刚阳为尊。地以柔阴而卑。则乾坤之体定矣。若天不刚阳。地不柔阴。是乾坤之
体不定矣。夫干道成男。男自子位左旋。积三十岁而至巳。所以男及三十而娶。当是之时。天
阳已刚也。坤道成女。自子位右旋。积二十岁而至巳。所以女二十而嫁。至斯之际。地阴以
顺也。故及其时得子皆强。所谓干。坤之体定矣。不及其时而嫁娶者。则刚阳柔阴。必有所
亏也。
回答说：男子以精为根本，女子以血为源头。男子属阳，阳中必含有阴，阴的成数对应八，所以男子八岁时阳精开始下降（发育），十六岁时阳精满溢（具备生殖能力）。女子属阴，阴中必含有阳，阳的成数对应七，所以女子七岁时阴血开始上升（发育），十四岁时阴血满溢（月经来潮，具备生殖能力）。阳精和阴血，都是饮食五味精华的体现，是男女生命的本源。当精血处于“升”的阶段时，人的智力思虑变得开明，牙齿更换生长，脱落的头发重新变黑，虚弱的筋骨变得强健。到了精血“溢”的阶段，全身肢体、手足耳目等所有部位，哪怕是像针尖芥子那样微小的地方，没有不到达滋养的。凡是子女形貌肖似父母的原因，是因为父母的精血曾在父母身体各处无所不至地运行过。因此，如果父亲有一只肢体残疾，那么子女就有一处肢体不像父母；如果父亲有一只眼睛失明，那么子女就有一只眼睛不像父母。然而，雌鸡和母兽在没有天癸（性成熟标志）的情况下也能受孕，这是为什么呢？因为鸟兽的精血往来是通过尾闾穴进行的。男子在精气未通之时就与女子交合泄精，会导致五体有不完备之处，日后会有难以名状的疾病。男子阴茎已痿软却仍贪恋女色而强行泄精，则精液排不出而在体内败坏，导致尿道涩滞而成淋证。精气已经耗损却又继续枯竭。女子天癸既已到来，若超过十年没有与男子交合，则月经不调；未满十年就与男子交合，也会导致月经不调。月经不调则旧血不能排出，新血错误运行，有的渗入骨骼，有的变为肿块。或者虽然能与男子交合但难以怀孕。与男子交合过多，则会耗竭津液使人体虚弱；生育哺乳众多，则会因血枯而致死。观察精血的道理，思虑便过半了。
回答说：天以刚健之阳为尊，地以柔顺之阴为卑，这样乾坤的形体就确定了。如果天不刚阳，地不柔阴，那么乾坤的形体就不确定了。乾道成就男性，男性从子位（北方/冬至）左旋，积累三十岁到达巳位（东南/立夏），所以男子到三十岁才娶妻。在这个时候，天的阳气已经刚健。坤道成就女性，从子位右旋，积累二十岁到达巳位，所以女子到二十岁才出嫁。到了这个时候，地的阴气已经顺承。所以在适当的时机得到子女，子女都强壮，这就是所谓的乾坤形体确定。不及适当时机就嫁娶的，那么刚阳和柔阴必然有所亏损。
Answer: Men take Jing (Essence) as the root, and women take Blood as the source. Men belong to Yang; within Yang there must be Yin, and the number associated with Yin is eight. Therefore, at age eight, the Yang Essence begins to descend (develop); at age sixteen, the Yang Essence overflows (becomes capable of reproduction). Women belong to Yin; within Yin there must be Yang, and the number associated with Yang is seven. Therefore, at age seven, the Yin Blood begins to ascend (develop); at age fourteen, the Yin Blood overflows (menstruation begins, becoming capable of reproduction). Yang Essence and Yin Blood are both the essence derived from the five flavors of food and drink, serving as the fundamental source for men and women. During the phase of "ascending," intelligence and thought become clear, teeth are replaced, hair that has fallen out turns black again, and weak sinews and bones become strong. Upon reaching the phase of "overflowing," every part of the body, including limbs, hands, feet, ears, eyes, and even minute areas like needle points or mustard seeds, receives nourishment. The reason why children resemble their parents is that the parents' Jing and Blood have circulated throughout the parents' bodies without exception. Thus, if a father has a disabled limb, the child will have a corresponding limb that does not resemble the parent; if a father has a defective eye, the child will have an eye that does not resemble the parent. However, female chickens and female beasts can conceive without Tian Gui (the substance related to sexual maturity and reproductive function in TCM). Why is this? Because in birds and beasts, the circulation of Jing and Blood passes through the Wei Jian acupoint (located at the tailbone). If a man engages in intercourse and releases his Jing before his Jing is fully connected and mature, his five organs and tissues will have incomplete aspects, leading to difficult-to-describe illnesses later in life. If a man's penis is already flaccid but he still desires sexual gratification and forces the release of Jing, the Jing will not exit but will instead rot internally, causing obstruction in the urinary pathway resulting in Lin syndrome (painful urination). If Jing is exhausted and then further depleted, damage occurs. Once a woman's Tian Gui has arrived, if she remains without intercourse with a man for more than ten years, her menstruation will become irregular; if she has intercourse with a man before ten years have passed since the arrival of her Tian Gui, it will also lead to irregular menstruation. Irregular menstruation means old blood fails to discharge, and new blood flows erroneously; some may seep into the bones, while others may transform into swellings or masses. Even if she has intercourse, she may find it difficult to conceive. Frequent intercourse with men depletes fluids and causes weakness in the person; bearing many children and nursing frequently leads to Blood depletion and can be fatal. By observing the principles of Jing and Blood, one understands half of the matter.
Answer: Heaven respects rigid Yang, and Earth honors soft Yin; thus, the forms of Qian (Heaven) and Kun (Earth) are established. If Heaven were not rigidly Yang and Earth were not softly Yin, the forms of Qian and Kun would not be stable. The Dao of Qian produces males; males rotate counter-clockwise starting from the Zi position (North/Winter Solstice), accumulating thirty years until reaching the Si position (Southeast/Lixia). Therefore, men marry at thirty. At this time, Heavenly Yang is fully vigorous. The Dao of Kun produces females; females rotate clockwise starting from the Zi position, accumulating twenty years until reaching the Si position. Therefore, women marry at twenty. At this juncture, Earthly Yin is compliant. Hence, offspring conceived at the appropriate time are robust, signifying that the forms of Qian and Kun are fixed. Those who marry before the appropriate time cause Rigidity/Yang and Softness/Yin to be deficient.