It means that the relationship between men and women comes from instinct, but etiquette must be followed.
This sentence comes from the "Book of Songs". It is said that the first chapter of the "Book of Songs" deleted by Confucius, "Guan Ju", describes a young man who cannot sleep because he longs for a woman. Zi Fu, a student of Confucius, said that "it is all about emotion but not about propriety and justice", which is what Confucius advocated, "pleasure but not obscenity".
Extended information:
The Book of Songs is the earliest poetry collection in the history of Chinese literature. It contains 305 poems (first 11 century to the 6th century BC), there are another 6 poems with titles but no content, that is, with goals but no words, which are called Sheng poems. The Book of Songs in the pre-Qin Dynasty was called "Poetry", or the whole number was called "Poetry Three Hundred". It was revered as a Confucian classic during the Western Han Dynasty and was first called the Book of Songs, which is still used today. This compilation chose Zhu Xi's "Collected Poems" as the base, which had a huge influence and was very popular after the Song Dynasty.
The author of "The Book of Songs" is unknown, and most of it cannot be verified. It is said that it was collected by Yin Jifu and compiled by Confucius. The Book of Songs was called "The Book of Songs" in the pre-Qin period, or the round number was called "The Three Hundred Songs". It was revered as a Confucian classic during the Western Han Dynasty and was first called the Book of Songs, which is still used today. The Book of Songs is divided into three parts: "Wind", "Ya" and "Song". "Wind" is a ballad from various places in the Zhou Dynasty; "Ya" is a formal song of the Zhou people, and is divided into "Xiaoya" and "Daya"; Song", "Song of Lu" and "Song of Shang".
Confucius once summarized the purpose of the "Book of Songs" as "innocence" and taught his disciples to read the "Book of Songs" as the standard for speech and action. Among the pre-Qin scholars, many quoted the Book of Songs. For example, Mencius, Xunzi, Mozi, Zhuangzi, Han Feizi, etc. often quoted sentences from the Book of Songs to enhance their persuasiveness when reasoning and demonstrating. By the time of Emperor Wu of the Han Dynasty, the Book of Songs was regarded as a classic by Confucianists and became one of the Six Classics and the Five Classics.
Confucius once summarized the purpose of the "Book of Songs" as "innocence" and taught his disciples to read the "Book of Songs" as the standard for speech and action. Among the pre-Qin scholars, many quoted the Book of Songs. For example, Mencius, Xunzi, Mozi, Zhuangzi, Han Feizi, etc. often quoted sentences from the Book of Songs to enhance their persuasiveness when reasoning and demonstrating. By the time of Emperor Wu of the Han Dynasty, the Book of Songs was regarded as a classic by Confucianists and became one of the Six Classics and the Five Classics.
The Analects of Confucius mentions "Poetry" (i.e. "The Book of Songs") many times, but the only work that makes specific evaluation is "Guanyong", which is called "happy but not obscene, sad." without hurting”.