A gentleman is a man who knows the book and is polite. He must be modest about what others like, because he may also have something he likes. If someone takes it away, he will be sad. Therefore, from yourself to others, you can't do anything that makes others sad. Only a villain would do that.
There is a similar saying in "Zengguang Xianwen": "Sages don't show their abilities, and gentlemen don't take advantage of others." It means: sages don't try to be brave, and gentlemen don't plunder what others like. Therefore, a gentleman should keep good conduct.
Gentleman's famous saying
1, gentleman, villain. -"The Analects of Confucius, Xianwen"
2. A gentleman who is not heavy is not arrogant. -The Analects of Confucius
3. an upright man is open and poised while a petty man is anxious and worried. -The Analects of Confucius
4. If a gentleman is not kind, he has a husband, and a benevolent person has no villain. -"The Analects of Confucius, Xianwen"
5, the gentleman is poor, and the villain is poor. -"The Analects of Confucius Wei Linggong"