陈飞霞曰∶幼科指纹，总无正论，且游移不定，莫可稽驳。有谓不必用者，有用而至于怪诞不经，诬民惑世
者，是皆未明纹
中之理，所以有用不用之殊议。请以一得之愚，聊发其要。盖此指纹，与寸关尺同一脉也，按《内经》十二
经络，始于手太阴，其支者从腕后出次指之端，而交于手阳明，此即指纹是也。明如景岳，犹谓此纹为手阳明
浮脉。不知手太阴经起于中府，而终大拇指之少商；手阳明经起于食指商阳，两不相值，若无此旁支交通营卫，
不几令太阴阳明表里断绝乎。况此脉可诊，人所不知。其迟数代促，与太渊一毫无异，但脉体差小，由旁支也。
指纹之法，起于宋人钱仲阳。以食指分三关，寅曰风关，卯曰气关，辰曰命关。其诀谓风轻气重命危，虽未必
其言悉验，而其义可取。
涂蔚生曰∶十二经皆有动脉，非独阳明太阴为然。如足阳明之趺阳，足少阴之太溪，皆以动脉之所在，古人
以之遍诊病症。取太渊以诊大人者，以其肺为华盖，会朝百脉也。取三关以诊小儿者，以其太渊细小，脉形未
全，不如三关之明了以视也。执定肺与大肠相为表里为解、以三关之指纹、即太渊之支出者，似乎过拘，而尚为
精确之谈也。独针灸所谓之足厥阴太冲穴，在足大指本节后动脉处，遍寻细审，毫未见其动脉焉。余曾访问多人，
令其细为审察，亦云无有。不知此穴此脉，究在何处？想古人审脉定穴，未必敢从意断，当阙以待考。
陈飞霞说：儿科指纹诊断，向来没有统一的定论，而且说法游移不定，无法考证驳正。有的人认为不需要使用，有的人虽然使用却流于怪诞不经、欺骗民众迷惑世人的地步，这些都是因为没有明白指纹背后的道理，所以才会有用与不用的不同议论。请允许我凭借浅陋的见解，简要阐述其要点。大概这指纹，与寸关尺三部脉是同一性质的脉象。按照《内经》十二经络的理论，经脉始于手太阴肺经，其分支从腕后出于食指末端，然后交于手阳明大肠经，这就是所谓的指纹。即使是像张景岳那样明理的人，也还说这条纹是手阳明经的浮脉。却不知道手太阴肺经起于中府穴，终于大拇指少商穴；手阳明大肠经起于食指商阳穴，两者并不直接相连。如果没有这个旁支来交通营卫之气，岂不是让太阴和阳明这两表里经断绝联系了吗？况且这条脉是可以诊察的，只是人们不知道罢了。它的迟数代促等变化，与太渊脉毫无差异，只是脉体较小，因为它是旁支的缘故。
指纹诊法，起源于宋代钱乙（钱仲阳）。他将食指分为三关，第一节叫风关，第二节叫气关，第三节叫命关。他的口诀说“风轻气重命危”，虽然未必完全验证，但其义理值得采纳。
涂蔚生说：十二经脉都有动脉，不仅仅是阳明和太阴经如此。比如足阳明胃经的趺阳脉，足少阴肾经的太溪脉，都是根据动脉所在的位置，古人用它来遍诊病症。选取太渊脉来诊察成人，是因为肺为华盖，汇聚百脉。选取三关来诊察小儿，是因为小儿的太渊脉细小，脉形尚未完全形成，不如三关部位明显易于观察。如果固执地用“肺与大肠相表里”来解释，认为三关的指纹就是太渊脉的分支，似乎过于拘泥，但还算是一种精确的说法。唯独针灸所说的足厥阴肝经太冲穴，位于足大指本节后的动脉处，我仔细寻找审察，丝毫没见到有动脉存在。我曾访问多人，让他们仔细审察，也说没有。不知道这个穴位和这条脉，究竟在哪里？想古人审察脉象确定穴位，未必敢凭空臆断，应当存疑以待考证。
Chen Feixia stated: In pediatric medicine, the diagnosis by fingerprint (Fingerprint Diagnosis) has never had a definitive theory, and interpretations are inconsistent and difficult to verify. Some claim it is unnecessary to use, while others, though using it, resort to absurdities that deceive the public and confuse the world. These views arise from a failure to understand the principles underlying the fingerprints, leading to divergent opinions on its utility. Permit me to offer my humble insights to briefly elucidate the essentials. Essentially, this fingerprint is the same type of pulse as those at the Cun, Guan, and Chi positions. According to the *Neijing* (Classic of Internal Medicine), the twelve meridians begin with the Hand-Taiyin Lung Meridian. Its branch emerges from behind the wrist to the tip of the index finger, where it connects with the Hand-Yangming Large Intestine Meridian; this is what is referred to as the fingerprint. Even Zhang Jingyue, known for his clarity, claimed this line represents the floating pulse of the Hand-Yangming meridian. He failed to realize that the Hand-Taiyin meridian originates at Zhongfu (LU-1) and terminates at Shaoshang (LU-11) on the thumb, while the Hand-Yangming meridian originates at Shangyang (LI-1) on the index finger; they do not directly meet. Without this collateral branch to facilitate the communication of Ying and Wei (Nutritive and Defensive Qi), would this not sever the exterior-interior relationship between Taiyin and Yangming? Moreover, this pulse is diagnosable, though people are unaware of it. Its variations in slowness, rapidity, intermission, and urgency are identical to those of the Taiyuan pulse, differing only in being smaller because it is a collateral branch.
The method of fingerprint diagnosis originated with Qian Zhongyang (Qian Yi) of the Song Dynasty. He divided the index finger into three sections: the first section is called the Wind Section (Feng Guan), the second the Qi Section (Qi Guan), and the third the Life Section (Ming Guan). His aphorism states, "Light wind indicates mild illness, heavy qi indicates severe illness, and reaching the life section indicates danger." Although this may not be entirely accurate in every case, its theoretical basis is valuable.
Tu Weisheng stated: All twelve meridians have palpable arteries, not just the Yangming and Taiyin meridians. For instance, the Duyang pulse of the Foot-Yangming Stomach Meridian and the Taixi pulse of the Foot-Shaoyin Kidney Meridian are located where arteries are palpable, and ancient physicians used them for comprehensive diagnosis. The Taiyuan pulse is selected for diagnosing adults because the Lung is the canopy of the viscera and converges all pulses. The three sections of the finger are selected for diagnosing children because the Taiyuan pulse is too fine and the pulse shape is not fully developed in infants, whereas the three sections are clearer and easier to observe. Interpreting this strictly through the principle that the Lung and Large Intestine are exterior-interior pairs, and thus claiming the three-section fingerprint is merely an extension of the Taiyuan pulse, seems somewhat rigid, yet it remains a precise explanation. However, regarding the acupuncture point Taichong (LR-3) of the Foot-Jueyin Liver Meridian, which is said to be located at the arterial pulsation behind the metatarsophalangeal joint of the great toe, I have searched carefully but found no such artery. I consulted many people and asked them to examine closely, and they also reported finding none. It remains unknown where this specific acupoint and pulse actually lie. One may assume that ancient physicians did not arbitrarily determine pulses and acupoints based on speculation alone; rather, this should remain as a question awaiting further verification.