一、少阴解义
少阴为三阴的枢机。病至少阴已然到了一个关键的时刻，为什么呢？这与少阴的内涵是很有关联的。下面拟从四个方面来探讨少阴的内涵。1.少阴本义
少阴的本义其实就是水火的本义。按照常识，水火是不相容的，可是在少阴里，水火却要相依相容。
（1）坎水义
首先我们来研究水，水在易卦中属坎，故习称坎水。郑钦安的《医理真传》中有一首坎卦诗，颇得坎水之旨趣，姑录于下。诗曰：天施地孕水才通，一气含三造化工，万物根基从此立，生生化化沐时中。
① 坎水之形成
易讲乾坤生六子，三男三女，哪三男呢？就是长男震雷，中男坎水，少男艮山。所以，坎水实为乾坤所生六子中的一子。郑诗首句“天施地孕水才通”即为此义。乾天坤地，乾父坤母，故乾坤交媾而有六子之生。那么，坎水中男这一子是怎么生出来的呢？就是由乾坤二卦之中爻相交，若乾交坤，坤之中爻变阳，即生坎中满。若坤交乾，乾之中爻变阴，则生离中虚。乾之中爻交坤而生坎，坤虽变坎，而余体尚在。故坤坎同居，水土合德。坤德为藏，坎德亦为藏。藏什么呢？其实就是藏的这坎中之阳。坎中之阳源自先天，故称真阳、元阳，亦称命门火、龙火。有关此阳，我们在太阴篇讲四逆汤的时候已经提到过。此阳此火宜潜藏而不宜飞越，那靠什么来潜藏呢？除了坎德本身之藏以外，尚需依赖坤德之藏。所以，水土合德的关系不但在太阴篇里很重要，在少阴篇里仍然不能轻视这个关系。② 真阳命火上述坎水中之阳亦称真阳、元阳、龙火、命火，由这个称谓便知它是人身中绝顶重要的东西。有它才有生命，无它便无生命可言。而这样一个绝顶重要的东西亦就有一个绝顶重要的特性，这就是上面说的宜潜藏而不宜飞越。所谓真人不露相，露相非真人。真阳、命火为什么要潜藏呢？因为潜藏了才能温养生气，才能让生气旭旭而生、煦煦而养，如此生命乃得久长。如果真阳不得潜藏，或者将真阳派作其他用场，那这个生气便得不到温养，连生气都不得温养，你想生命怎么不危机四伏呢？所以，真阳、命火的涵藏性于生命是绝顶重要的。如果失于涵藏，那真阳外越的诸多危证便会随之发生。我们看少阴篇和厥阴篇，有相当多的内容就是讨论的这个问题。少阴病为什么有戴阳证、格阳证？许多危重病人临终前为什么会出现回光返照？这其实就是真阳外越的一个征兆。在人身有这样一个真阳、命火来温养生气，使生命得以延续。而人与天地相应，在自然里，在我们生存的这个地球上，有没有一个类似的真阳、命火，以使我们地球的生气得以不断延续呢？有！这就是寄藏于坎水之中，埋藏于坤土里的，大家所熟知的能源。我们现在使用的主要能源有石油、煤与天然气，这些能源要么藏于海底，要么深埋于地下。这与人身真阳、命火的涵藏处非常一致。而且石油是以液体的，也就是与水相似的形式存在的。煤虽为固体结构，可是其色黑，既然色黑，那就脱不了水的干系。石油、煤、天然气，这些能源的蕴藏量都不是无限的，照这般开采下去，用不了多久就会枯竭。等这些能源枯竭了，未来的人类用什么能源呢？2000年 10月 28日的《参考消息》，有篇题为“未来能源在海底”的文章。文章指出，未来洁净能源的最大一部分也许在海底，它是以冰冷的冰块晶体的形式存在，这就是水合甲烷。由上述讨论我们看到，无论是现在的能源还是未来的能源，都无一例外的蕴藏于坎水中、坤体里，这与人身之真阳、命火何其相似！这使我们联想到一个非常重要的问题。我们这个地球为什么会有生命呢？很重要的一个前提就是它有生气。有这个生气才会有生命，包括植物生命和动物生命。要是没这个生气，一切生命都是泡影，都不可能。而这个生气的来源就是上述的“真阳、命火”。可见，我们现在所开采和运用的这些深藏于海底和地下的能源是有专门用场的。地球的生气就要靠它来温养，地球生命的前提就要靠它来保障。能源即是地球的“真阳”，能源即是地球的“命火”，所以，它就应该潜藏。惟有潜藏，方能温养地球的生气。现在将这些“真阳”、“命火”大量地开采出来以供我们日用，这个过程实际是一个什么过程呢？实际是一个我们人为的使地球“真阳”、“命火”外越的过程。大家可以仔细地思考，看是不是这么回事。随着地球“真阳”、“命火”的大量外越，地球生气的温养来源也就逐渐减少。生气日少，生命的前提没有了保障，我们生存的这个地球怎么不危机四伏呢？当然就危机四伏了。所以，我们看人类对待地球其实就像人对待我们自身一样。现代科学虽然不知道什么“真阳”、“命火”，可是她毕竟清楚这样无限制的开采能源对人类的将来没有什么好处。而人呢？《内经》早就讲到人应该“恬淡虚无”，因为“恬淡虚无，真气从之，精神内守，病安从来”。其实很多人都知道这个道理，都知道“恬淡”的好处，可是他还是偏偏要贪嗔，要物欲横流，要以酒为浆，以妄为常。就像抽烟，没有几个抽烟的人不知道抽烟的害处。更有趣的是烟草的广告。在所有的广告中，无不是“黄婆卖瓜，自卖自夸”，都是一分好处说成十分。惟有烟草的广告不然，它只告诉你“吸烟有害健康！”可尽管这样，烟草的消费还是与日俱增。这就提醒我们，人的问题，人类的问题不是光靠科学就能解决，还需要哲学，还需要宗教。世界应该是多极化，同样的，文化也应该是多极化、多元化。由以上分析，我们看到了地球的“真阳”、“命火”正在遭受日益的外泄。现在整个地表的温度为什么会逐年增高？冰川为什么日渐融化？这其实就是地球“真阳”、“命火”外越的一个显兆。这其实就是“戴阳证”、“格阳证”。所以，如果我们从伤寒的角度，用六经的眼光，来为我们所处的地球号一号脉，那么，地球已然处于少阴病的阶段。我们怎样来为地球“回阳”？怎样来为地球“救逆”呢？这实在是全人类应该共同思考的大问题！（2）离火义诗云：地产天成号火王，阴阳互合隐维皇，神明出入真无定，个里机关只伏藏。有关离火的意义，我们亦从郑氏的这首诗开始。① 离火的形成从郑氏离卦诗的开首句“地产天成号火王”，可知离火的形成亦是乾坤交媾的结果。乾坤交媾，由乾之中爻交坤，坤之中爻变阳，即得到我们上面讨论的坎水。反过来，由坤之中爻交乾，乾之中爻变阴，即形成离火。因此，离火与坎水正好相反，它是以乾为体的。前面我们提到易有乾坤生六子，三男三女。坎为水为阴却号男，离为火为阳却号女，为什么呢？这里面既有体用的关系，又有相依的关系，也有更值得我们思考的深层问题。阳言生化，阴言伏藏，此为常理。可是于郑诗中，坎水却言生化，离火却言伏藏，这与中男中女之称实有异曲同工之妙。此中的旨趣若能参透，阴阳至理便在把握之中了。这是离火的形成。② 离火的自然性用前面讲坎水是先从人身开始，讲离火我们把它倒过来，先从自然开始。离火的自然性用与特征，概括起来至少有六个方面。其一，热性。其二，明性。火之热明二性，皆为众所周知。其三，动力。火之动力性实在是造就现代科学的一个最大的因素。整个现代工业文明是怎么产生的呢？其实就是从认识火的动力性开始的。蒸汽机的发明就是一个最典型的例子。其四，熟物。生的东西经过火的作用就会变熟，可以说人类丰富的饮食文化就是由火来造就的。如果没有火，那我们只好像其他动物一样食用生的食物。其五，变化。火的变化作用是显而易见的。冰是固体，经火的作用很快就变成液体，而液体再经火的作用又可以变成气态。学过化学，对火的变化作用会更清楚，为什么大多数化学反应都有加热的过程？为的就是加速变化，促进变化。其六，但见其用，无形可征。前面我们曾经谈到，人类与其他动物最大的一个区别就是能够主动用火。主动用火的涵义有两个方面，一方面是没有火他可以主动去寻找火，现在我们开采石油，开采天然气实际上就是寻找火；另一方面就是人类能够主动地发现火的上述性能并加以利用。而其他的一切动物都不具备这个能力。是什么改变了人类文明的进程，是什么使社会如此飞速的发展呢？说到底就是这个火。火的作用如此重要，而火在发挥这些作用的时候又有一个十分独特的地方，这就是我们此处讨论的“但见其用，无形可征”。在五行里，除火以外的其他物质，都有一个具体的形体供我们查征。比如木，它有一个很具体的形，我们可以拿它来做成方桌，也可以用它来做成圆桌，金土也有这个“可形性、可塑性”。水虽没有这样固定的形体，可它还是有形可征的。而惟有火不具备这个共性，你只能强烈地感受到它的作用，却看不到它“可形、可塑”的特征。五行中独火无形，而《老子》里亦有一个无形，这就是“大象无形”。这个无形的大象有什么性用呢？《老子》又云：“执大象，天下往。”由此看来，火之所以能够彻底地改变整个人类，火之所以有如此重要的作用，与此无形的特性，与此大象的特性是分不开的。③ 火之身用火的自然性用已如上述，正如《内经》所言：“善言天者，必应于人。”故知火于人身，或者说阳气于人身的性用，亦不离上述六个方面。其一，温热身体。人活着的时候都有体温，这个体温靠什么呢？就靠火的温热之性。所以，我们只要从身上的冷暖、手足的冷暖，就可以知道人身的火、人身的阳气充不充足。其二，视物光明。人的眼睛为什么能看见这个世界呢？靠的也是这个火、这个阳气。我们只知道肝开窍于目，目受血而能视，这还不行。我们更应该清楚肝是体阴而用阳。目之视物更在于这南明离火。人的岁数一大，两眼就昏花，就易生诸障，这就是因为阳火虚衰的缘故。其三，人身的机能活动。人的精力靠什么呢？主要就是靠这个阳火。这与火的动力效应是非常相像的。人到少阴病的时候，为什么会但欲寐？为什么一动也不想动？为什么心脏的搏动力渐渐减弱？就是因为火在日渐地衰弱。其四，人胃腐熟水谷的功能与火的熟物是很相应的。所以，我们就知道胃是靠火来腐熟的。如果胃火不足，那吃下去的东西就不能腐熟，拉出来的还是这些东西。如果胃火太过了，那就要消谷善饥，吃多少都不知道饱。其五，人的一生处于不断的变化之中，用现代一些的语言，这就叫新陈代谢。变化也好，代谢也好，它靠的什么？还是火。这与火在自然的变化性用是一致的。其六，上面我们谈到，“但见其用，无形可征”是火的一个最重要、最独特的地方，这一个最重要和独特的地方在人身与什么相应呢？很显然，它是与神明相应。神明的作用可以说是人身中最最重要的，它无处不在，无处不用。故而《素问·灵兰秘典论》云：“心者，君主之官，神明出焉。”如果神明的作用丧失了，那会是一个什么情况呢？这就如张仲景于《伤寒杂病论》序中所言：“厥身已毙，神明消灭，变为异物，幽潜重泉，徒为啼泣。”神明的作用如此重要，可以说有它才有生命，无它则无生命可言。但是，神明是一个什么形状？神明是一个什么样子呢？这却难以言清难以道明。故《中庸》曰：“视之而弗见，听之而弗闻，体物而不可遗，使天下之人齐明。”故《诗》曰：“神之格思，不可度思，矧可射思？”神其谓欤！五行中，火是但见其用，无形可征的。而在人身，神明由心所主，心与其他四藏有什么区别呢？这一点好像前面谈到过，除心以外，其他各藏的造字都有一个月肉傍，有月肉就有形可征，有形可鉴。所以，肝、脾、肺、肾各藏皆有一个具体的形状。而惟独心缺少月肉傍，没有月肉，那当然就无形可征，无形可鉴了。从五行火的特性，从五藏心的造字，从神明的特征，我们对中医赖以建立的这个基础，对中医的基本理念，应该有一个比较深刻的认识。中医虽然是有关人的医学，可是为什么《内经》却要强调搞中医必须谈天论地呢？因为你不谈天，不论地，这个人就弄不清楚，人弄不清楚，怎么可能把中医搞好呢？（3）同名少阴上面我们讲了坎水和离火，坎水和离火在人身它归到哪里呢？都归到了少阴。水火本不相容，可是在人身它不仅要相容，而且还同叫一个名字，这是为什么呢？下面就来讨论这个问题。① 水火者，血气之男女也水火同名少阴，一方面是强调水火在人身的重要性，另一方面则强调水火这两个东西一定要配合好。水火要相依，不能相离，如果一相离，那就会出问题。为什么呢？《素问·阴阳应象大论》里说得很清楚，水火是什么？水火就是阴阳。阴阳是什么呢？阴阳就是男女。所以，人身的水火就是人身的阴阳，就是人身的男女。一对男女住在同一个宅子里，这是什么呢？当然是夫妻。是夫妻就要相依，就要夫唱妇随。过去妻到夫家都要随夫姓，所以，水火同名少阴，这个涵义是很深刻的。阴阳、男女、水火宜和合、宜相依，前面讲太阴的时候，曾举过《易·系辞》的一段话：“天地絪缊，万物化醇。男女构精，万物化生。
一、少阴解义
少阴是三阴经的枢纽。病邪传至少阴时，已经到达了一个关键的时刻，这是为什么呢？这与少阴的内涵密切相关。下面打算从四个方面来探讨少阴的内涵。
1. 少阴本义
少阴的本义其实就是水与火的本义。按照常识，水和火是不相容的，但在少阴中，水火却要相互依存、相互包容。
（1）坎水的意义
首先我们来研究水，水在《易经》卦象中属于坎卦，所以习惯称为坎水。郑钦安的《医理真传》中有一首关于坎卦的诗，很得坎水的精髓，姑且录在下面。诗写道：天施地孕水才通，一气含三造化工，万物根基从此立，生生化化沐时中。
① 坎水的形成
《易经》讲乾坤生出六子，即三男三女，哪三个男孩呢？就是长男震雷，中男坎水，少男艮山。所以，坎水实际上是乾坤所生的六子中的一个儿子。郑诗的第一句“天施地孕水才通”就是这个意思。乾为天，坤为地，乾为父，坤为母，所以乾坤交媾而生出六个子女。那么，作为中男的坎水这个儿子是怎么生出来的呢？就是由乾坤两卦的中爻相交，如果乾交于坤，坤的中爻变为阳爻，就生出坎卦（中间实，故称坎中满）。如果坤交于乾，乾的中爻变为阴爻，就生出离卦（中间虚，故称离中虚）。乾的中爻交于坤而生出坎卦，坤虽然变成了坎，但其余部分还在。所以坤和坎同居，水土合德。坤的德性是藏，坎的德性也是藏。藏什么呢？其实就是藏的这坎中的阳气。坎中的阳气源自先天，所以称为真阳、元阳，也称为命门火、龙火。关于这个阳气，我们在太阴篇讲四逆汤的时候已经提到过。这个阳气、这个火宜潜藏而不宜飞越，那靠什么来潜藏呢？除了坎德本身的藏以外，还需要依赖坤德的藏。所以，水土合德的关系不仅在太阴篇里很重要，在少阴篇里也不能轻视这个关系。
② 真阳命火
上述坎水中的阳气也称为真阳、元阳、龙火、命火，从这些称谓就可以知道它是人身中绝顶重要的东西。有它才有生命，没有它便谈不上生命。而这样一个绝顶重要的东西也有一个绝顶重要的特性，这就是上面说的宜潜藏而不宜飞越。所谓真人不露相，露相非真人。真阳、命火为什么要潜藏呢？因为潜藏了才能温养生气，才能让生气旭日般升起、温暖地滋养，如此生命才能长久。如果真阳不能潜藏，或者将真阳派作其他用场，那么这个生气就得不到温养，连生气都不得温养，你想生命怎么会不危机四伏呢？所以，真阳、命火的涵藏性对于生命是绝顶重要的。如果失于涵藏，那么真阳外越的诸多危重证候便会随之发生。我们看少阴篇和厥阴篇，有相当多的内容就是讨论这个问题的。少阴病为什么会有戴阳证、格阳证？许多危重病人临终前为什么会出现回光返照？这其实就是真阳外越的一个征兆。在人身有这样一个真阳、命火来温养生气，使生命得以延续。而人与天地相应，在自然界中，在我们生存的地球上，有没有一个类似的真阳、命火，以使我们地球的生气得以不断延续呢？有！这就是寄藏于坎水中，埋藏于坤土里的，大家所熟知的能源。我们现在使用的主要能源有石油、煤与天然气，这些能源要么藏于海底，要么深埋于地下。这与人身真阳、命火的涵藏处非常一致。而且石油是以液体的形式存在的，也就是与水相似。煤虽为固体结构，可是其色黑，既然色黑，那就脱不了水的干系。石油、煤、天然气，这些能源的蕴藏量都不是无限的，照这般开采下去，用不了多久就会枯竭。等这些能源枯竭了，未来的人类用什么能源呢？2000年10月28日的《参考消息》，有篇题为“未来能源在海底”的文章。文章指出，未来洁净能源的最大一部分也许在海底，它是以冰冷的冰块晶体的形式存在，这就是水合甲烷。由上述讨论我们看到，无论是现在的能源还是未来的能源，都无一例外地蕴藏于坎水中、坤体里，这与人身之真阳、命火何其相似！这使我们联想到一个非常重要的问题。我们这个地球为什么会有生命呢？很重要的一个前提就是它有生气。有这个生气才会有生命，包括植物生命和动物生命。要是没这个生气，一切生命都是泡影，都不可能。而这个生气的来源就是上述的“真阳、命火”。可见，我们现在所开采和运用的这些深藏于海底和地下的能源是有专门用场的。地球的生气就要靠它来温养，地球生命的前提就要靠它来保障。能源即是地球的“真阳”，能源即是地球的“命火”，所以，它就应该潜藏。惟有潜藏，方能温养地球的生气。现在将这些“真阳”、“命火”大量地开采出来以供我们日用，这个过程实际是一个什么过程呢？实际是一个我们人为地使地球“真阳”、“命火”外越的过程。大家可以仔细地思考，看是不是这么回事。随着地球“真阳”、“命火”的大量外越，地球生气的温养来源也就逐渐减少。生气日少，生命的前提没有了保障，我们生存的这个地球怎么不危机四伏呢？当然就危机四伏了。所以，我们看人类对待地球其实就像人对待我们自身一样。现代科学虽然不知道什么“真阳”、“命火”，可是她毕竟清楚这样无限制的开采能源对人类的将来没有什么好处。而人呢？《内经》早就讲到人应该“恬淡虚无”，因为“恬淡虚无，真气从之，精神内守，病安从来”。其实很多人都知道这个道理，都知道“恬淡”的好处，可是他还是偏偏要贪嗔，要物欲横流，要以酒为浆，以妄为常。就像抽烟，没有几个抽烟的人不知道抽烟的害处。更有趣的是烟草的广告。在所有的广告中，无不是“黄婆卖瓜，自卖自夸”，都是一分好处说成十分。惟有烟草的广告不然，它只告诉你“吸烟有害健康！”可尽管这样，烟草的消费还是与日俱增。这就提醒我们，人的问题，人类的问题不是光靠科学就能解决，还需要哲学，还需要宗教。世界应该是多极化，同样的，文化也应该是多极化、多元化。由以上分析，我们看到了地球的“真阳”、“命火”正在遭受日益的外泄。现在整个地表的温度为什么会逐年增高？冰川为什么日渐融化？这其实就是地球“真阳”、“命火”外越的一个显兆。这其实就是“戴阳证”、“格阳证”。所以，如果我们从伤寒的角度，用六经的眼光，来为我们所处的地球号一号脉，那么，地球已然处于少阴病的阶段。我们怎样来为地球“回阳”？怎样来为地球“救逆”呢？这实在是全人类应该共同思考的大问题！
（2）离火的意义
诗写道：地产天成号火王，阴阳互合隐维皇，神明出入真无定，个里机关只伏藏。
有关离火的意义，我们也从郑氏的这首诗开始。
① 离火的形成
从郑氏离卦诗的开首句“地产天成号火王”，可知离火的形成亦是乾坤交媾的结果。乾坤交媾，由乾的中爻交于坤，坤的中爻变为阳爻，即得到我们上面讨论的坎水。反过来，由坤的中爻交于乾，乾的中爻变为阴爻，即形成离火。因此，离火与坎水正好相反，它是以乾为体的。前面我们提到易有乾坤生六子，三男三女。坎为水为阴却号男，离为火为阳却号女，为什么呢？这里面既有体用的关系，又有相依的关系，也有更值得我们思考的深层问题。阳言生化，阴言伏藏，此为常理。可是于郑诗中，坎水却言生化，离火却言伏藏，这与中男中女之称实有异曲同工之妙。此中的旨趣若能参透，阴阳至理便在把握之中了。这是离火的形成。
② 离火的自然性用
前面讲坎水是先从人身开始，讲离火我们把它倒过来，先从自然开始。离火的自然性用与特征，概括起来至少有六个方面。其一，热性。其二，明性。火的热性和明性，皆为众所周知。其三，动力。火的动力性实在是造就现代科学的一个最大的因素。整个现代工业文明是怎么产生的呢？其实就是从认识火的动力性开始的。蒸汽机的发明就是一个最典型的例子。其四，熟物。生的东西经过火的作用就会变熟，可以说人类丰富的饮食文化就是由火来造就的。如果没有火，那我们只好像其他动物一样食用生的食物。其五，变化。火的变化作用是显而易见的。冰是固体，经火的作用很快就变成液体，而液体再经火的作用又可以变成气态。学过化学，对火的变化作用会更清楚，为什么大多数化学反应都有加热的过程？为的就是加速变化，促进变化。其六，但见其用，无形可征。前面我们曾经谈到，人类与其他动物最大的一个区别就是能够主动用火。主动用火的涵义有两个方面，一方面是没有火他可以主动去寻找火，现在我们开采石油，开采天然气实际上就是寻找火；另一方面就是人类能够主动地发现火的上述性能并加以利用。而其他的一切动物都不具备这个能力。是什么改变了人类文明的进程，是什么使社会如此飞速的发展呢？说到底就是这个火。火的作用如此重要，而火在发挥这些作用的时候又有一个十分独特的地方，这就是我们此处讨论的“但见其用，无形可征”。在五行里，除火以外的其他物质，都有一个具体的形体供我们查征。比如木，它有一个很具体的形，我们可以拿它来做成方桌，也可以用它来做成圆桌，金土也有这个“可形性、可塑性”。水虽没有这样固定的形体，可它还是有形可征的。而惟有火不具备这个共性，你只能强烈地感受到它的作用，却看不到它“可形、可塑”的特征。五行中独火无形，而《老子》里亦有一个无形，这就是“大象无形”。这个无形的大象有什么性用呢？《老子》又云：“执大象，天下往。”由此看来，火之所以能够彻底地改变整个人类，火之所以有如此重要的作用，与此无形的特性，与此大象的特性是分不开的。
③ 火之身用
火的自然性用已如上述，正如《内经》所言：“善言天者，必应于人。”故知火于人身，或者说阳气于人身的性用，亦不离上述六个方面。其一，温热身体。人活着的时候都有体温，这个体温靠什么呢？就靠火的热温之性。所以，我们只要从身上的冷暖、手足的冷暖，就可以知道人身的火、人身的阳气充不充足。其二，视物光明。人的眼睛为什么能看见这个世界呢？靠的也是这个火、这个阳气。我们只知道肝开窍于目，目受血而能视，这还不行。我们更应该清楚肝是体阴而用阳。目之视物更在于这南明离火。人的岁数一大，两眼就昏花，就易生诸障，这就是因为阳火虚衰的缘故。其三，人身的机能活动。人的精力靠什么呢？主要就是靠这个阳火。这与火的动力效应是非常相像的。人到少阴病的时候，为什么会但欲寐？为什么一动也不想动？为什么心脏的搏动力渐渐减弱？就是因为火在日渐地衰弱。其四，人胃腐熟水谷的功能与火的熟物是很相应的。所以，我们就知道胃是靠火来腐熟的。如果胃火不足，那吃下去的东西就不能腐熟，拉出来的还是这些东西。如果胃火太过了，那就要消谷善饥，吃多少都不知道饱。其五，人的一生处于不断的变化之中，用现代一些的语言，这就叫新陈代谢。变化也好，代谢也好，它靠的什么？还是火。这与火在自然的变化性用是一致的。其六，上面我们谈到，“但见其用，无形可征”是火的一个最重要、最独特的地方，这一个最重要和独特的地方在人身与什么相应呢？很显然，它是与神明相应。神明的作用可以说是人身中最最重要的，它无处不在，无处不用。故而《素问·灵兰秘典论》云：“心者，君主之官，神明出焉。”如果神明的作用丧失了，那会是一个什么情况呢？这就如张仲景于《伤寒杂病论》序中所言：“厥身已毙，神明消灭，变为异物，幽潜重泉，徒为啼泣。”神明的作用如此重要，可以说有它才有生命，无它则无生命可言。但是，神明是一个什么形状？神明是一个什么样子呢？这却难以言清难以道明。故《中庸》曰：“视之而弗见，听之而弗闻，体物而不可遗，使天下之人齐明。”故《诗》曰：“神之格思，不可度思，矧可射思？”神其谓欤！五行中，火是但见其用，无形可征的。而在人身，神明由心所主，心与其他四藏有什么区别呢？这一点好像前面谈到过，除心以外，其他各藏的造字都有一个月肉傍，有月肉就有形可征，有形可鉴。所以，肝、脾、肺、肾各藏皆有一个具体的形状。而惟独心缺少月肉傍，没有月肉，那当然就无形可征，无形可鉴了。从五行火的特性，从五藏心的造字，从神明的特征，我们对中医赖以建立的这个基础，对中医的基本理念，应该有一个比较深刻的认识。中医虽然是有关人的医学，可是为什么《内经》却要强调搞中医必须谈天论地呢？因为你不谈天，不论地，这个人就弄不清楚，人弄不清楚，怎么可能把中医搞好呢？
（3）同名少阴
上面我们讲了坎水和离火，坎水和离火在人身它归到哪里呢？都归到了少阴。水火本不相容，可是在人身它不仅要相容，而且还同叫一个名字，这是为什么呢？下面就来讨论这个问题。
① 水火者，血气之男女也
水火同名少阴，一方面是强调水火在人身的重要性，另一方面则强调水火这两个东西一定要配合好。水火要相依，不能相离，如果一相离，那就会出问题。为什么呢？《素问·阴阳应象大论》里说得很清楚，水火是什么？水火就是阴阳。阴阳是什么呢？阴阳就是男女。所以，人身的水火就是人身的阴阳，就是人身的男女。一对男女住在同一个宅子里，这是什么呢？当然是夫妻。是夫妻就要相依，就要夫唱妇随。过去妻到夫家都要随夫姓，所以，水火同名少阴，这个涵义是很深刻的。阴阳、男女、水火宜和合、宜相依，前面讲太阴的时候，曾举过《易·系辞》的一段话：“天地絪缊，万物化醇。男女构精，万物化生。”
I. Interpretation of Shaoyin
Shaoyin is the pivot of the three Yin meridians. When a disease reaches Shaoyin, it has arrived at a critical moment. Why is this? This is closely related to the connotation of Shaoyin. Below, we intend to explore the connotation of Shaoyin from four aspects.
1. The Original Meaning of Shaoyin
The original meaning of Shaoyin is actually the original meaning of Water and Fire. According to common sense, Water and Fire are incompatible; however, in Shaoyin, Water and Fire must coexist and be compatible.
(1) The Meaning of Kan Water
First, let us study Water. In the hexagrams of the *I Ching* (Book of Changes), Water belongs to Kan, so it is commonly referred to as Kan Water. In Zheng Qin'an's *Yi Li Zhen Chuan* (True Transmission of Medical Principles), there is a poem about the Kan hexagram that captures the essence of Kan Water quite well. It is recorded below. The poem reads: "Heaven imparts, Earth conceives, only then does Water flow through; One Qi contains Three, creating the wonders of nature; From here stands the foundation of all things, Generating and transforming, bathed in the seasons."
① The Formation of Kan Water
The *I Ching* states that Qian (Heaven) and Kun (Earth) generate six children, three sons and three daughters. Who are the three sons? They are the Eldest Son Zhen (Thunder), the Middle Son Kan (Water), and the Youngest Son Gen (Mountain). Therefore, Kan Water is actually one of the six children generated by Qian and Kun. The first line of Zheng's poem, "Heaven imparts, Earth conceives, only then does Water flow through," refers to this meaning. Qian is Heaven, Kun is Earth; Qian is Father, Kun is Mother. Thus, through the union of Qian and Kun, the six children are born. So, how was this son, Kan Water, the Middle Son, born? It was born through the intersection of the middle lines of the Qian and Kun trigrams. If Qian intersects with Kun, and the middle line of Kun changes to Yang, Kan (full in the middle) is generated. If Kun intersects with Qian, and the middle line of Qian changes to Yin, Li (empty in the middle) is generated. The middle line of Qian intersects with Kun to generate Kan. Although Kun transforms into Kan, the rest of its structure remains. Thus, Kun and Kan reside together, and Earth and Water combine their virtues. The virtue of Kun is storage/concealment, and the virtue of Kan is also storage/concealment. What is stored? It is precisely the Yang Qi within Kan. The Yang Qi within Kan originates from the Pre-heaven (innate constitution), so it is called True Yang, Primordial Yang, or also Mingmen Fire (Gate of Life Fire) and Dragon Fire. Regarding this Yang Qi, we have already mentioned it when discussing Si Ni Tang (Counter-Junction Decoction) in the Taiyin chapter. This Yang Qi and this Fire should be concealed rather than flying away. What relies on for concealment? Besides the inherent concealment of Kan's virtue, it still needs to rely on the concealment of Kun's virtue. Therefore, the relationship of Earth and Water combining virtues is not only important in the Taiyin chapter but cannot be neglected in the Shaoyin chapter either.
② True Yang and Ming Fire
The Yang within the aforementioned Kan Water is also called True Yang, Primordial Yang, Dragon Fire, and Ming Fire. From these names, one can know that it is something of supreme importance in the human body. With it, there is life; without it, there is no talk of life. And such a supremely important thing has a supremely important characteristic, which is what was said above: it should be concealed rather than flying away. As the saying goes, a true master does not reveal himself; if he reveals himself, he is not a true master. Why must True Yang and Ming Fire be concealed? Because only when concealed can they warm and nourish Sheng Qi (Vital Qi), allowing Vital Qi to rise like the morning sun and be nurtured warmly, thus ensuring longevity of life. If True Yang cannot be concealed, or if True Yang is diverted for other uses, then this Vital Qi will not receive warmth and nourishment. If even Vital Qi does not receive warmth and nourishment, how can you expect life not to be fraught with crisis? Therefore, the concealment of True Yang and Ming Fire is of supreme importance to life. If concealment is lost, various critical syndromes of True Yang floating outward will occur accordingly. Looking at the Shaoyin and Jueyin chapters, a considerable amount of content discusses this very issue. Why do Shaoyin diseases present with Dai Yang Syndrome (Floating Yang Syndrome) and Ge Yang Syndrome (Rejecting Yang Syndrome)? Why do many critically ill patients experience terminal lucidity before death? This is actually a sign of True Yang floating outward. In the human body, having such True Yang and Ming Fire to warm and nourish Vital Qi allows life to continue. Since humans correspond to Heaven and Earth, in nature, on our living earth, is there a similar True Yang or Ming Fire to ensure the continuous continuation of the Earth's Vital Qi? Yes! This is the energy source everyone is familiar with, hidden in Kan Water and buried in Kun Earth. The main energy sources we use now are petroleum, coal, and natural gas. These energy sources are either hidden under the sea or deeply buried underground. This is very consistent with the concealment sites of True Yang and Ming Fire in the human body. Moreover, petroleum exists in liquid form, similar to water. Although coal has a solid structure, its color is black; since it is black, it is inseparable from Water. The reserves of petroleum, coal, and natural gas are not infinite. If mined in this manner, they will be depleted soon. When these energy sources are depleted, what energy will future humans use? On October 28, 2000, the *Reference News* published an article titled "Future Energy Sources Under the Sea." The article points out that the largest part of future clean energy may lie under the sea, existing in the form of cold ice crystals, namely methane hydrate. From the above discussion, we see that whether current or future energy sources, without exception, are stored in Kan Water and Kun Earth. How similar this is to True Yang and Ming Fire in the human body! This makes us think of a very important question. Why does our earth have life? A very important premise is that it has Vital Qi. Only with this Vital Qi is there life, including plant and animal life. Without this Vital Qi, all life would be an illusion, impossible. And the source of this Vital Qi is the aforementioned "True Yang" and "Ming Fire." It is evident that the energy sources we currently mine and utilize, deeply hidden under the sea and underground, have a specific purpose. The Vital Qi of the earth relies on it for warming and nourishing, and the premise of life on earth relies on it for guarantee. Energy is the Earth's "True Yang"; energy is the Earth's "Ming Fire." Therefore, it should be concealed. Only by being concealed can it warm and nourish the Earth's Vital Qi. Now, mining these "True Yang" and "Ming Fire" in large quantities for our daily use—what kind of process is this actually? It is actually a process where we artificially cause the Earth's "True Yang" and "Ming Fire" to float outward. Everyone can think carefully about whether this is the case. With the massive outward floating of the Earth's "True Yang" and "Ming Fire," the source of warming and nourishing the Earth's Vital Qi gradually decreases. Vital Qi diminishes day by day, and the premise of life loses its guarantee. How can the earth we live on not be fraught with crisis? Of course, it is fraught with crisis. Thus, we see that humanity's treatment of the earth is actually like a person's treatment of their own body. Although modern science does not know what "True Yang" or "Ming Fire" is, it is clear that such unlimited mining of energy is not beneficial for the future of humanity. And what about people? The *Nei Jing* (Inner Canon) long ago stated that people should be "tranquil and empty" (Tian Dan Xu Wu), because "when tranquil and empty, True Qi follows; when spirit and mind are kept inward, how can disease arise?" Actually, many people know this principle and know the benefits of "tranquility," yet they still indulge in greed and anger, allow material desires to run rampant, treat wine as water, and regard absurdity as normal. Just like smoking; few smokers do not know the harms of smoking. More interestingly are tobacco advertisements. Among all advertisements, none is not "selling one's own wares with exaggerated praise," turning one part benefit into ten. Only tobacco advertisements are different; they only tell you "Smoking is harmful to health!" Yet despite this, tobacco consumption continues to increase daily. This reminds us that the problems of individuals and humanity cannot be solved by science alone; philosophy and religion are also needed. The world should be multipolar; similarly, culture should be multipolar and diversified. From the above analysis, we see that the Earth's "True Yang" and "Ming Fire" are suffering from increasing leakage. Why is the temperature of the entire earth's surface increasing year by year? Why are glaciers melting day by day? This is actually a manifestation of the Earth's "True Yang" and "Ming Fire" floating outward. This is exactly "Dai Yang Syndrome" and "Ge Yang Syndrome." Therefore, if we view our earth through the lens of Shang Han Lun (Treatise on Cold Damage) and the Six Meridians perspective, taking the pulse of the earth, then the earth has already entered the stage of Shaoyin Disease. How shall we "restore Yang" for the earth? How shall we "save against counterflow" for the earth? This is truly a major issue that all humanity should jointly contemplate!
(2) The Meaning of Li Fire
The poem reads: "Produced by Earth, formed by Heaven, called King of Fire; Yin and Yang mutually combine, hiding the Great Sovereign; Spirit and Mind enter and exit, truly without fixed form; The mechanism within lies only in concealment."
Regarding the meaning of Li Fire, we also begin with Zheng's poem.
① The Formation of Li Fire
From the opening line of Zheng's Li Hexagram poem, "Produced by Earth, formed by Heaven, called King of Fire," it is known that the formation of Li Fire is also the result of the union of Qian and Kun. Through the union of Qian and Kun, the middle line of Qian intersects with Kun, and the middle line of Kun changes to Yang, yielding the Kan Water discussed above. Conversely, the middle line of Kun intersects with Qian, and the middle line of Qian changes to Yin, forming Li Fire. Therefore, Li Fire is exactly opposite to Kan Water; it takes Qian as its substance. Earlier, we mentioned that the *I Ching* states Qian and Kun generate six children, three sons and three daughters. Kan is Water and Yin, yet is called Male; Li is Fire and Yang, yet is called Female. Why? This involves both the relationship of substance and function, and a relationship of mutual dependence, as well as deeper issues worthy of our contemplation. Yang speaks of generation and transformation; Yin speaks of concealment and storage. This is the general rule. However, in Zheng's poem, Kan Water speaks of generation and transformation, while Li Fire speaks of concealment and storage. This shares a similar subtlety with the titles of Middle Son and Middle Daughter. If the essence here can be penetrated, the profound principles of Yin and Yang are grasped. This is the formation of Li Fire.
② The Natural Functions and Characteristics of Li Fire
Earlier, when discussing Kan Water, we started from the human body. When discussing Li Fire, we reverse it and start from nature. The natural functions and characteristics of Li Fire can be summarized into at least six aspects. First, Heat Nature. Second, Illumination Nature. The heat and illumination of fire are well-known to all. Third, Dynamic Power. The dynamic nature of fire is actually the greatest factor in creating modern science. How did the entire modern industrial civilization arise? It actually began with the understanding of the dynamic nature of fire. The invention of the steam engine is the most typical example. Fourth, Cooking/Ripening Things. Raw things become cooked through the action of fire. It can be said that human rich dietary culture was created by fire. Without fire, we would have to eat raw food like other animals. Fifth, Transformation. The transformative effect of fire is obvious. Ice is solid; through the action of fire, it quickly becomes liquid, and liquid through fire can become gaseous. Those who have studied chemistry understand the transformative role of fire better; why do most chemical reactions involve heating? It is to accelerate change and promote transformation. Sixth, Only its function is seen, no form can be traced. We previously mentioned that the biggest difference between humans and other animals is the ability to actively use fire. The meaning of actively using fire has two aspects: on one hand, without fire, one can actively seek fire; now, mining petroleum and natural gas is essentially seeking fire; on the other hand, humans can actively discover the aforementioned properties of fire and utilize them. No other animals possess this ability. What changed the course of human civilization? What made society develop so rapidly? Ultimately, it is this fire. Fire plays such an important role, and when fire exerts these effects, it has a very unique feature, which is what we are discussing here: "Only its function is seen, no form can be traced." In the Five Elements, except for Fire, all other substances have a specific physical form for us to observe. For example, Wood has a very specific shape; we can make square tables or round tables from it. Metal and Earth also have this "formability and plasticity." Although Water does not have such a fixed shape, it still has a traceable form. Only Fire lacks this commonality; you can strongly feel its effect, but you cannot see its "formable and plastic" characteristics. Among the Five Elements, only Fire is formless. And in the *Laozi*, there is also a mention of formlessness, which is "The Great Image has no form." What are the functions of this formless Great Image? The *Laozi* further says: "Hold the Great Image, and the world comes to you." From this, it seems that the reason Fire can thoroughly change all of humanity, and the reason it has such an important role, is inseparable from this formless characteristic and the characteristic of the Great Image.
③ The Bodily Functions of Fire
The natural functions of Fire have been described above. As the *Nei Jing* states: "Those who speak well of Heaven must correspond to Man." Thus, we know that the functions of Fire in the human body, or Yang Qi in the human body, do not depart from the above six aspects. First, Warming the Body. Living humans have body temperature; what relies on this? It relies on the warming nature of Fire. Therefore, by observing the warmth or coldness of the body and limbs, we can know whether the Fire and Yang Qi in the human body are sufficient. Second, Illuminating Vision. Why can human eyes see this world? It relies on this Fire and this Yang Qi. We only know that the Liver opens into the Eyes, and the Eyes see when nourished by Blood; this is not enough. We should more clearly understand that the Liver has Yin as substance and Yang as function. Vision depends even more on this Southern Bright Li Fire. As people age, their eyes become dim and prone to various obstructions; this is due to the deficiency and decline of Yang Fire. Third, Bodily Functional Activities. What does human energy rely on? Mainly this Yang Fire. This is very similar to the dynamic effect of Fire. When one suffers from Shaoyin Disease, why is there only a desire to sleep? Why does one not want to move at all? Why does the pumping power of the heart gradually weaken? It is because Fire is gradually declining. Fourth, the Stomach's function of rotting and ripening food corresponds well with Fire's cooking function. Thus, we know the Stomach relies on Fire for rotting and ripening. If Stomach Fire is insufficient, the food eaten cannot be rotted and ripened, and what is excreted is still the same stuff. If Stomach Fire is too excessive, one will digest food quickly and feel hungry easily, never knowing satiety regardless of how much one eats. Fifth, a person's life is in constant change; in modern terms, this is called metabolism. Whether change or metabolism, what does it rely on? Still Fire. This is consistent with the transformative function of Fire in nature. Sixth, as mentioned above, "Only its function is seen, no form can be traced" is the most important and unique aspect of Fire. What does this most important and unique aspect correspond to in the human body? Obviously, it corresponds to Shen Ming (Spirit and Mind). The function of Shen Ming can be said to be the most important in the human body; it is everywhere and used everywhere. Thus, the *Su Wen: Ling Lan Mi Dian Lun* states: "The Heart is the Official of the Monarch, from whom Shen Ming emerges." If the function of Shen Ming were lost, what would the situation be? This is as Zhang Zhongjing said in the preface to *Shang Han Za Bing Lun*: "The body perishes, Shen Ming vanishes, turning into a strange object, hidden deep in the springs, vainly weeping." The function of Shen Ming is so important; one can say that with it there is life, without it there is no life. But what shape does Shen Ming have? What does it look like? This is difficult to describe clearly. Thus, the *Zhong Yong* (Doctrine of the Mean) says: "Look at it, and you do not see it; listen to it, and you do not hear it; it embodies all things and leaves nothing out, causing all people in the world to purify themselves." And the *Shi Jing* (Book of Odes) says: "When the Spirit arrives, it cannot be measured; how much less can it be abandoned?" Is this referring to Spirit? Among the Five Elements, Fire is only seen in its function, with no form to trace. In the human body, Shen Ming is governed by the Heart. What is the difference between the Heart and the other four Zang organs? As mentioned earlier, apart from the Heart, the characters for all other Zang organs contain the "flesh" radical (月/肉). Having flesh means having a traceable form and visible appearance. Thus, the Liver, Spleen, Lung, and Kidney each have a specific shape. Only the Heart lacks the flesh radical; without flesh, naturally, it has no traceable form and no visible appearance. From the characteristics of Fire in the Five Elements, from the character construction of the Heart among the Five Zang organs, and from the characteristics of Shen Ming, we should have a relatively profound understanding of the foundation upon which Traditional Chinese Medicine (TCM) is built and the basic concepts of TCM. Although TCM is a medicine concerning humans, why does the *Nei Jing* emphasize that those practicing TCM must discuss Heaven and Earth? Because if you do not discuss Heaven and Earth, you cannot understand humans. If you cannot understand humans, how can you practice TCM well?
(3) Named Together as Shaoyin
Above we discussed Kan Water and Li Fire. Where do Kan Water and Li Fire belong in the human body? They both belong to Shaoyin. Water and Fire are originally incompatible, but in the human body, not only must they be compatible, but they also share the same name. Why is this? Let us discuss this issue below.
① Water and Fire are the Male and Female of Blood and Qi
Water and Fire sharing the name Shaoyin emphasizes, on one hand, the importance of Water and Fire in the human body, and on the other hand, emphasizes that these two things must cooperate well. Water and Fire must depend on each other and cannot separate; if they separate, problems will arise. Why? The *Su Wen: Yin Yang Ying Xiang Da Lun* states very clearly: What are Water and Fire? Water and Fire are Yin and Yang. What are Yin and Yang? Yin and Yang are Male and Female. Therefore, Water and Fire in the human body are Yin and Yang in the human body, and Male and Female in the human body. A male and female living in the same house—what is this? Of course, husband and wife. Husband and wife must depend on each other, with the husband leading and the wife following. In the past, wives took their husband's surname upon entering the family. Therefore, the meaning of Water and Fire sharing the name Shaoyin is very profound. Yin and Yang, Male and Female, Water and Fire should be harmonious and interdependent. Earlier, when discussing Taiyin, we cited a passage from the *Xi Ci* (Commentary on the Appended Phrases) of the *I Ching*: "Heaven and Earth mingle, and all things become pure; Males and females join essence, and all things are born."