Let the other person do a great deal of the talking
When trying to convince someone, we can start by listening what they have to say. [@carnegie2010How to win friends & influence people] gives a couple of examples of why listening is always better than just talking. It can be summarized to the fact of not knowing what the other person's problems are. We could try to impose (with kids, for example) without knowing what frustrates the other person and why they don't do what we want them to do.
Literature note: The Leader in You - Dale Carnegie
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