The author of this article in the Encyclopedia of Taoism is a classic sinologist Isabelle Robinet, and all five quotations are great illustrations of what the Chinese people think on heart-mind, and the Westerners on heart. I like to read and reread my synopsis more and more due to tones in Pinyin which I will be never tired to put but which are not exist in the official edition.
“The term xīn traditionally designates the ruler of the entire person or, more specifically, the heart as the organ of mental and affective life (hence the translation as “heart-mind”). It is the “master” or “ruler” (zhŭ 主) of ideas, thought, will, and desire: many words expressing mental or affective activities (e.g., yì 意 “intention, idea,” sī 思 “thinking,” ài 愛 “love,” and wù 惡 “hate”) have xīn as their semantic indicator.”
“As a physiological organ the heart is depicted as a lotus flower with three petals. It is said that the heart of a worldly person has five openings, the heart of an average person has seven, and the heart of a sage has nine. The heart is abode of the spirit, and its “gates” are the mouth and tongue.”
“Being the center, xīn represents the center of the world and is located in the three Cinnabar Fields (dāntián 丹田). Hence there are three xīn: a celestial one above that generates the essence (jīng 精), a terrestrial one below that generates pneuma (qì 氣), and a human one in the middle that generates blood. In this view, the center of the body is not the spleen but the heart. Moreover, as it is also located in the head, xīn also denotes what is on high. Whether it is above or in the center, these two locations are equivalent, as they are those of the master and the central “palace” of the body.”
“In neidan texts, xīn takes on a new meaning. The “spirit of the Dao” is the Ultimate Truth, absolute and subtle and present in every human being. The “human spirit,” on the other hand, is both the heart-mind and the spirit; it is weak and frail. Rénxīn and dàoxīn, nevertheless, are one and the same, as they are only two aspects of the Ultimate Truth: rénxīn is the function (yong) and the mechanism (ji) of dàoxīn.”
“In reality xīn cannot be located either in space or in time. It is the Real Emptiness (zhēnwú 真無) to be found in everyday existence and in the phenomenal world. Finding it means rejoining daoxin and renxin. In so far as it is situated at the junction between movement and quiescence (dong and jing), Non-being and Being, xīn is the Ultimateless or Infinite (wújí) that is before the Great Ultimate (tàijí), before the beginning of the differentiation between movement and quiescence .”