The inner diameter records that the heart corresponds to the viscera and tongue, and the five elements belong to fire, with bitter taste and red color. How can there be a health book that says that the heart supplements the ears and the kidney supplements the two yin, but the inner diameter records the correspondence of the ears? ... The Huangdi Neijing did introduce that the kidney is the second yin to enlighten the mind.

The first statement: the heart is in the tongue, the lung is in the nose, the liver is in the eyes, the spleen is in the mouth, and the kidney is in the ear.

The second statement: the liver is in the eye, the lung is in the nose, the heart is in the ear, the spleen is in the mouth and tongue, and the kidney is in the second yin.

Inner diameter: synopsis of the golden chamber is an outline, which contains: south red, pain in the heart, understanding in the ear, essence in the heart; The north is black, entering the kidney, inducing resuscitation and yin, and storing essence in the kidney. The first statement is the revision of the inner diameter by later generations, which remains to be discussed and uncertain.

Therefore, it is accurate to say that the internal diameter record is that the kidney is enlightened by two yin and the heart is enlightened by the ear. Later generations took the initiative to modify it to "the heart begins to understand the tongue (not to understand)"

It is not unified in the field of traditional Chinese medicine. Briefly introduce several good explanations for reference: First, kidney opening and two yin refers to male yin and female yin (non-modern medical cognition). Second, the heart is on the top, belonging to the fire, with warm and upward characteristics, which can make Yin and Yang Qi and blood flow to the ears, so the heart is enlightened to the ears. The kidney is in the lower position, belonging to water, and has the characteristics of descending, so I began to understand the two yin, the main reproduction, and the management of the two stools. Third, the kidney dominates the ear as Yin, the heart begins to show the ear as Yang, and the kidney (water) and heart (fire) dominate the hearing. Fourth, the tongue is the heart, and the mouth is the gateway to the heart. The head of the ear enters the heart of Qihengfu, which belongs to the five internal organs, so the heart is used to enlighten the ear. Both of them, one is out (mouth) and the other is in (ear), both of which are the knowledge of the heart.