I've been thinking about this for a while.

Naturally, you listen to someone more closely (i.e. with more respect) when you perceive that they are speaking to you from a position of higher power.

The key point though, is that this 'power' is open to your perception, and may change from person to person. This is why while Bob really respects what Alice has to say, Charles could pay it no mind. Fundamentally, Charles thinks Alice is speaking from a position beneath him, and that her words are of no value to him.

Additionally, humans are very good at determining whether someone else is coming from a position of power within moments of meeting them. This leaves me with two questions in mind:

1) If thrown into a new social circle with, how does one create the image that he has power and ensure that he holds that position?

2) How does one deemed to be in the middle or lower half of the pecking order of a particular social circle rise above and 'earn' respect?