The meaning of this sentence is that Confucius said: "A gentleman should think carefully about the nine phases, consider seeing clearly, hearing clearly and understanding clearly;" When you treat people, you should consider whether your face is gentle or not; When dealing with people, we should consider whether the attitude is solemn and respectful, whether we are honest and honest when talking with people, and whether we are serious and cautious when doing things. When you are in trouble, you should consider asking others. When you are angry, you should consider whether it will cause future trouble. When you see wealth, you should consider whether it is suitable for righteousness. "