程鸣谦云∶褚澄氏言男女交合，阴血先至，阳精后冲，而男形成；阳精先入，阴血后参
，而女形成，信斯言也。人有精先泄而生男，精后泄而生女者，独何欤？东垣曰∶经水才断
一二日，血海始净，感者成男；四五日血脉已旺，感者成女；至于六七日后，则虽交感，亦
不成胎，信斯言也。人有经始断交合生女，经久断交合生男者，亦有四五日以前交合无孕，
八九日以后交合有孕者，独何欤？俞子木撰《广嗣要略》，着方立图，谓实阳能入虚阴，实
阴不能受阳，即东垣之故见也。又谓微阳不能射阴，弱阴不能摄阳，信斯言也。世有 羸之
夫，怯弱之妇，屡屡受胎，虽欲止之而不能止者，亦有血气方刚，精力过人，顾乃艰于育嗣
，而莫之救者，独何欤？朱丹溪论治，专以妇人经水为主，然富贵之家，侍外家已多，其中宁
无月水当期者乎？有已经前夫频频生育，而娶此以图其易者，顾亦不能得胎，更道与他人，
转盼生男矣，岂不能受孕于此，而能受孕于彼乎？愚以为父母之生子，如天地之生物。《易
》曰∶坤道其顺乎，承天而时行（承天之行，乃是至理，然有不毛之地，岂坤道不顺乎）。夫知地之生物，不过须承乎
天；
则知母之生子，亦不过顺
承乎父而已。知母之须承乎父，则种子者，果以妇人为主乎？以男子为主乎？然所谓主于男子
者，不拘老少强弱，康宁病患，精易泄难泄，只以交感之时，百脉齐到为善耳。交感而百脉
齐到，虽老弱病患易泄，亦可以成胎；交感而百脉参差，虽少强、虽康宁、虽难泄，亦难以
成胎矣。妇人所构之血，固由于百脉合聚，较之男子之精，不能无轻重之分也。孔子赞干元
，资始曰大，赞坤元，资生曰至，得无意乎。若男女之辨，又不以精血先后为拘，不以经尽
几日为拘，不以夜半前后交感为拘，不以父强母弱，母强父弱为拘，只以精血各由百脉齐到
者别胜负耳。是故精之百脉齐到，有以胜乎血，则成男矣；血之百脉齐到，有以胜乎精，则
成女矣。至有既孕而小产者，有产而不育，有育而不寿者，有寿而黄者无疆者，则亦精
血之坚脆，分为修短耳。世人不察其精血之坚脆，已定于禀受之初，乃以小产专责之母，以
不育专付之儿，以寿夭专诿之数，不亦谬乎？
程鸣谦说：褚澄认为，男女交合时，如果阴血先到达，阳精随后进入，就会形成男胎；如果阳精先进入，阴血随后参与，就会形成女胎。相信这种说法是对的。但是，有的人在射精前泄精而生男孩，在射精后泄精而生女孩，这又是为什么呢？李东垣说：月经刚结束一两天，血海刚刚干净，此时受孕会生男孩；四五天时血脉已经旺盛，此时受孕会生女孩；到了六七日后，虽然进行交感，也不能成胎，相信这种说法是对的。但是，有的人月经刚结束就交合而生女孩，月经结束后很久才交合而生男孩；也有的人在月经结束四五日前交合没有怀孕，而在八九日之后交合却怀孕了，这又是为什么呢？俞子木撰写《广嗣要略》，制定方剂并绘制图表，认为阳气充实才能进入虚弱的阴中，阴气充实不能承受阳气，这是李东垣的旧有见解。他又说微弱的阳气不能射入阴中，虚弱的阴气不能摄持阳气，相信这种说法是对的。世间有身体瘦弱的丈夫和怯弱虚弱的妻子，屡次都能受孕，即使想要停止也停不下来；也有的人气血正旺盛，精力过人，反而难以生育后代，无人能救治他们，这又是为什么呢？朱丹溪论述治疗，专门以妇女的月经为主，然而富贵人家，侍奉外室（妾）已经很多了，其中难道没有按时来月经的吗？有的女子曾经被前夫频繁生育，娶她是为了图容易怀孕，结果却不能得子，再改嫁与他人，转眼就生了男孩，难道她能在此处不能受孕，却能在彼处受孕吗？我认为父母生子，就像天地化生万物。《易经》说：地道柔顺，承天而行（承天之行，乃是至理，然而有不毛之地，难道是地道不顺吗）。既然知道大地化生万物，不过是顺应上天；那么就知道母亲生子，也不过是顺承父亲罢了。既然知道母亲需要顺承父亲，那么种子（孕育胎儿），究竟是以妇人为主呢？还是以男子为主呢？然而所谓以男子为主，是不拘泥于年龄老少、体质强弱、健康或患病、精液易泄或难泄，只以交感之时，百脉之气同时到达为最好。交感时百脉之气同时到达，即使是年老体弱、患病、易泄精的人，也可以成胎；交感时百脉之气参差不齐，即使是年轻强壮、健康、难泄精的人，也难以成胎。妇人构成的血，固然由于百脉汇聚，但比起男子的精，不能没有轻重的分别。孔子赞颂乾元，资始称为大；赞颂坤元，资生称为至，这其中难道没有深意吗？至于男女的辨别，又不以精血先后为拘束，不以月经结束几天为拘束，不以半夜前后交感为拘束，不以父强母弱、母强父弱为拘束，只以精血各自由百脉同时到达的情况来区分胜负。因此，精的百脉同时到达，胜过血的百脉同时到达，就形成男胎；血的百脉同时到达，胜过精的百脉同时到达，就形成女胎。至于有怀孕后小产的，有生产后不能抚养长大的，有抚养长大但不长寿的，有长寿而子孙绵延无疆的，这也是因为精血的坚固与脆弱，决定了寿命的长短。世人不明察精血的坚固与脆弱，已在禀受之初就决定了，却将小产专门归咎于母亲，将不能抚养长大专门推给儿子，将寿夭专门推诿给命运，不也是错误的吗？
Cheng Mingqian stated: Chu Cheng said that during sexual intercourse, if the Yin blood arrives first and the Yang essence follows, a male fetus is formed; if the Yang essence enters first and the Yin blood participates subsequently, a female fetus is formed. Believing this statement is correct. However, some people conceive a son by ejaculating before emission, and a daughter by ejaculating after emission; why is this so? Li Dongyuan said: One to two days after menstruation ceases, when the Blood Sea (Xuehai) has just cleared, conception results in a male; four to five days later, when the blood vessels are vigorous, conception results in a female; after six or seven days, even with sexual intercourse, pregnancy cannot be achieved. Believing this statement is correct. However, some women conceive a daughter immediately after menstruation ends, and a son long after it ends; some do not conceive from intercourse within four or five days after menstruation ends, but do conceive from intercourse eight or nine days later; why is this so? Yu Zimu wrote *Guangsi Yaolüe* (Essentials for Prolonging Offspring), establishing prescriptions and diagrams, asserting that solid Yang can enter empty Yin, but solid Yin cannot receive Yang; this is merely an old view of Li Dongyuan. He further stated that slight Yang cannot shoot into Yin, and weak Yin cannot grasp Yang. Believing this statement is correct. In the world, there are emaciated husbands and timid, weak wives who repeatedly conceive, unable to stop even if they wish to; conversely, there are those with robust Qi and Blood and superior vitality who find it difficult to produce offspring, with no one able to save them; why is this so? Zhu Danxi discussed treatment, focusing primarily on women's menstruation. Yet, among wealthy families who have many concubines, are there none whose menstrual periods occur on schedule? Some women, having been frequently pregnant by a former husband, are married hoping for easy conception, yet fail to conceive; upon remarriage, they quickly bear sons. Can it be that they cannot conceive here but can conceive there? I believe that parents giving birth to children is like Heaven and Earth generating all things. The *I Ching* (Book of Changes) states: "The way of Kun (Earth) is its submission, receiving the movement of Qian (Heaven) and acting in accordance with time." (Receiving the movement of Heaven is indeed the highest principle, yet there are barren lands; does this mean the way of Kun is not submissive?). Knowing that the earth generates all things only by submitting to Heaven, we know that a mother bearing a child also only submits to the father. Knowing that the mother must submit to the father, then in seed-conception (Zizhong), is it primarily based on the woman or the man? However, what is meant by "primarily based on the man" is not constrained by age, strength, health, illness, or whether semen is easily or difficult to emit. It depends solely on whether, at the time of intercourse, the Qi of the Hundred Vessels (Baimai) arrives simultaneously. If the Qi of the Hundred Vessels arrives simultaneously during intercourse, even an old, weak, ill person who emits semen easily can achieve pregnancy; if the Qi of the Hundred Vessels is disparate during intercourse, even a young, strong, healthy person who finds it difficult to emit semen will struggle to achieve pregnancy. The blood constituted by the woman, although gathered from the Hundred Vessels, cannot be without distinction in weight compared to the man's essence. Confucius praised the Yuan of Qian, stating that providing origin is called Great; he praised the Yuan of Kun, stating that providing life is called Ultimate. Is there no profound meaning here? As for distinguishing male from female, it is not constrained by the sequence of essence and blood, nor by how many days after menstruation ends, nor by whether intercourse occurs before or after midnight, nor by whether the father is strong and the mother weak, or vice versa. It distinguishes victory and defeat solely by whether the essence and blood each arrive simultaneously via the Hundred Vessels. Therefore, if the simultaneous arrival of the Hundred Vessels in the essence surpasses that in the blood, a male is formed; if the simultaneous arrival of the Hundred Vessels in the blood surpasses that in the essence, a female is formed. Regarding those who miscarry after conception, those who give birth but cannot raise the child, those who raise the child but do not live long, and those who live long with boundless descendants, these are determined by the firmness or fragility of the essence and blood, which dictate longevity. People of the world, failing to observe that the firmness or fragility of essence and blood is fixed at the beginning of endowment, blame miscarriages solely on the mother, inability to raise children solely on the child, and longevity or premature death solely on fate. Is this not erroneous?