夫人之常数，太阳常多血少气，少阳常少血多气，阳明常多气多血，少阴常少血多气，厥阴常多血少气，
太阴常多气少血，此天之常数。足太阳与少阴为表里，少阳与厥阴为表里，阳明与太阴为表里，是为足阴
阳也。手太阳与少阴为表里，少阳与心主为表里，阳明与太阴为表里，是为手之阴阳也。今知手足阴阳所
苦，凡治病必先去其血，乃去其所苦，伺之所欲，然后泻有余，补不足。欲知背俞，先度其两乳间，中折
之，更以他草度去半已，即以两隅相拄也，乃举以度其背，令其一隅居上，齐脊大椎，两隅在下，当其下隅者，
肺之俞也。复下一度，心之俞也。复下一度，左角肝之俞也，右角脾之俞也。复下一度，肾之俞也。是谓五
脏之俞，灸刺之度也。形乐志苦，病生于脉，治
之以灸刺。形乐志乐，病生于肉，治之以针石。形苦志乐，病生于筋，治之以熨引。形苦志苦，病生于
咽嗌，治之以百药。形数惊恐，经络不通，病生于不仁，治之以按摩醪药。是谓五形志也。刺阳明出血气，刺
太阳出血恶气，刺少阳出气恶血，刺太阴出气恶血，刺少阴出气恶血，刺厥阴出血恶气也。
经脉别论∶跌仆（音赴）罢极（上音疲）如沤（下音瓯）
脏气法时论∶慧（音惠）淬（七内切）HT （乌开切）KT KT （音荒） 内（人朱切）
宣明五气篇∶翕（音吸） （音帝）窒（陡栗切）凝泣（涩）喑（读作音）
血气形志篇∶相柱（知庚切） （音铍）
人的生理常数中，太阳经通常血多气少，少阳经通常血少气多，阳明经通常气多血多，少阴经通常血少气多，厥阴经通常血多气少，太阴经通常气多血少，这是与生俱来的正常规律。足太阳膀胱经与足少阴肾经互为表里，足少阳胆经与足厥阴肝经互为表里，足阳明胃经与足太阴脾经互为表里，这构成了足三阴三阳的表里关系。手太阳小肠经与手少阴心经互为表里，手少阳三焦经与手厥阴心包经（心主）互为表里，手阳明大肠经与手太阴肺经互为表里，这构成了手三阴三阳的表里关系。现在了解了手足阴阳经脉容易发生的病变，大凡治疗疾病，必须先祛除瘀血，然后解除其痛苦，观察病情的虚实趋向，然后再泻其有余，补其不足。想要知道背部俞穴的位置，先测量两乳之间的距离，从中间折半，再用其他草茎量取剩余的一半长度，用这个长度作为两端距离来制作一个直角工具（或指用此长度在背部定位），将工具举起放在背上，让其一角位于上方，对齐脊柱的大椎穴，两个下角位于下方，正对下方那个角的部位，就是肺俞穴。再向下移动一个单位距离，是心俞穴。再向下移动一个单位距离，左边的角对应肝俞穴，右边的角对应脾俞穴。再向下移动一个单位距离，是肾俞穴。这就是五脏的背俞穴，也是艾灸和针刺的深度标准。形体安逸但精神苦恼，疾病产生于血脉，治疗用灸法和刺法。形体安逸且精神愉快，疾病产生于肌肉，治疗用针石（砭石）。形体劳苦但精神愉快，疾病产生于筋腱，治疗用热敷熨法和导引术。形体劳苦且精神苦恼，疾病产生于咽喉，治疗用各种药物。经常受到惊恐刺激，导致经络不通畅，疾病表现为麻木不仁，治疗用按摩和药酒。这被称为五种形体与情志的关系。针刺阳明经可放出血液和气，针刺太阳经可放出血液而避免耗气，针刺少阳经可排出气而避免放血，针刺太阴经可排出气而避免放血，针刺少阴经可排出气而避免放血，针刺厥阴经可放出血液而避免耗气。《经脉别论》中提到：跌倒、极度疲劳如同沤泡一般（形容气息短促或身体瘫软）。《脏气法时论》中提到：神志清明（慧）、昏乱（淬）、恍惚（HT/KT/荒）、内热（内）。《宣明五气篇》中提到：闭郁（翕）、闭塞（帝）、窒塞（窒）、凝涩（凝泣）、失音（喑）。《血气形志篇》中注释：相柱（知庚切）、铍（音铍，指砭石的一种）。
In the physiological constants of human beings, the Taiyang (Greater Yang) channel typically has abundant blood and scarce qi; the Shaoyang (Lesser Yang) channel typically has scarce blood and abundant qi; the Yangming (Yang Brightness) channel typically has abundant qi and abundant blood; the Shaoyin (Lesser Yin) channel typically has scarce blood and abundant qi; the Jueyin (Terminal Yin) channel typically has abundant blood and scarce qi; and the Taiyin (Greater Yin) channel typically has abundant qi and scarce blood. These are the natural constants. The Foot-Taiyang Bladder Channel and the Foot-Shaoyin Kidney Channel are exterior-interior paired; the Foot-Shaoyang Gallbladder Channel and the Foot-Jueyin Liver Channel are exterior-interior paired; the Foot-Yangming Stomach Channel and the Foot-Taiyin Spleen Channel are exterior-interior paired. This constitutes the exterior-interior relationships of the Foot-Yin and Foot-Yang channels. The Hand-Taiyang Small Intestine Channel and the Hand-Shaoyin Heart Channel are exterior-interior paired; the Hand-Shaoyang Sanjiao (Triple Burner) Channel and the Hand-Jueyin Pericardium Channel (Heart Master) are exterior-interior paired; the Hand-Yangming Large Intestine Channel and the Hand-Taiyin Lung Channel are exterior-interior paired. This constitutes the exterior-interior relationships of the Hand-Yin and Hand-Yang channels. Now that we understand the ailments to which the Hand and Foot Yin and Yang channels are prone, in treating diseases, one must first remove stagnant blood, thereby alleviating their distress. Then, observe the direction of the pathology (excess or deficiency), and subsequently drain the excess and tonify the deficiency. To locate the Back-Shu points on the back, first measure the distance between the two nipples, fold it in half, and then use another grass stem to measure half of the remaining length. Use this length as a reference for positioning. Place this measuring tool on the back, with one corner at the top, aligned with the Dazhui (GV14) acupoint on the spine, and the other two corners at the bottom. The point directly below the lower corner is the Feishu (BL13) acupoint of the Lung. Move down one unit distance, and you find the Xinshu (BL15) acupoint of the Heart. Move down one unit further; the left corner corresponds to the Ganshu (BL18) acupoint of the Liver, and the right corner corresponds to the Pishu (BL20) acupoint of the Spleen. Move down one unit again, and you find the Shenshu (BL23) acupoint of the Kidney. These are referred to as the Back-Shu points of the Five Zang organs, which also determine the depth for moxibustion and acupuncture. When the body is comfortable but the mind is distressed, diseases arise in the vessels; treat them with moxibustion and acupuncture. When both the body and the mind are comfortable, diseases arise in the flesh/muscles; treat them with needle-stone (bian stone). When the body is laborious but the mind is content, diseases arise in the sinews/tendons; treat them with hot compresses (warming therapy) and Dao Yin (qigong exercises). When both the body and the mind are distressed, diseases arise in the throat/pharynx; treat them with various herbs/medicines. Frequent fright and fear lead to blockage of the meridians and collaterals, resulting in diseases characterized by numbness and insensitivity; treat them with massage and medicinal wine. This is described as the "Five Forms and States of Mind." Acupuncture at the Yangming channel can release both blood and qi; acupuncture at the Taiyang channel can release blood while avoiding qi depletion; acupuncture at the Shaoyang channel can release qi while avoiding bloodletting; acupuncture at the Taiyin channel can release qi while avoiding bloodletting; acupuncture at the Shaoyin channel can release qi while avoiding bloodletting; and acupuncture at the Jueyin channel can release blood while avoiding qi depletion. *Jingmai Bie Lun* mentions: Falling or extreme exhaustion resembling foaming/bubbling (describing shortness of breath or physical collapse). *Zangqi Fashi Lun* mentions: Clarity of spirit (Hui), confusion (Cui), trance/dizziness (HT/KT/Huang), internal heat (Nei). *Xuanming Wuqi Pian* mentions: Closure/constriction (Xi), obstruction (Di), blockage (Zhi), coagulation/stagnation (Ning Qi), aphonia (Yin). *Xueqi Xingzhi Pian* annotations: Xiang Zhu (pronunciation guide), Pi (sound 'pi', referring to a type of bian stone).