Why prove to a man he is wrong? Is that going to make him like you? Why not let him save his face? He didn’t ask for your opinion. He didn’t want it.… - Dale Carnegie

Always avoid the acute angle.

To change somebody's behavior, change the level of respect she receives by giving her a fine reputation to live up to. Act as though the trait you are trying to influence is already one of the person's outstanding characteristics.

"There's magic, positive magic, in such phrases as: "I may be wrong. I frequently am. Let's examine the facts.

So if you aspire to be a good conversationalist, be an attentive listener. To be interesting, be interested. Ask questions that other persons will enjoy answering. Encourage them to talk about themselves and their accomplishments.