Instead of speaking to many, speak to one and let the many hear you.
(Nishio's translation) A good person speaks to one person, even if there are many people. And other people naturally listen to them. ysaito8015: writing in an easy-to-understand style...? / The story of a good person is told by many people, but only when it is said to one person is it heard by the people themselves. If a good person comes out from among many people and tells a story as if he sees it, all will laugh at him and laugh at him as well. modern translation
If you are a person of character, even if you are speaking to one person in a crowd, even the people around you will listen. Those who are not a person of character, with their guts on display, will interrupt and make up a story as if they had just seen it. It is noisy and annoying when everyone is laughing along with them.
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