[hindsightbias]

Anyone who listens for more than 20 seconds is over 110 IQ. People who talk mostly about other people rarely are.

[totololo]

Reminds me of this quote: "Great Minds Discuss Ideas. Average Minds Discuss Events. Small Minds Discuss People."

[chrisked]

Listening plus being very curious might be a good indicator. Smart people tend to understand that the world is complicated and there is always something to learn how it functions.

[therm0]

I know plenty of people who are extremely intelligent who only talk about themselves. Isn't social intelligence only one component of overall intelligence?

[9wzYQbTYsAIc]

Ability to think about others’ frame of mind is a kind of intelligence. You are probably referring to gossip, however.

Also, listening duration is a measure of attention not intelligence.