When you learn how to listen, you shut up. This has the added benefit of increasing your input, and if you're surrounding yourself with people smarter than you, that can only be a good thing.

Some people try to assert their intelligence by showing how well they can talk, be that by using speed or big words, but sometimes (most of the time) it has the opposite effect.

There is an unspoken rule among humans that we can't let silence hang. Some people take this rule to heart. What then happens is that the conversation is filled with filler, not things that actually help the conversation. Let the silence hang, speak when you have something to say.