Mishlei 13:1 - Listening to Authority

משלי יג:א

בֵּן חָכָם מוּסַר אָב וְלֵץ לֹא שָׁמַע גְּעָרָה:

Mishlei 13:1

A wise son [listens to] the discipline of his father, but a scoffer does not listen to rebuke.

Questions / Difficulties

1. Why does the pasuk emphasize the ben chacham (wise son) listening to the discipline of his father, specifically? Wouldn't the ben chacham listen to discipline from anyone? Moreover the second half of the pasuk talks about how the leitz (scoffer) reacts to any rebuke - not just the rebuke of his father. Why the asymmetry?
2. Why does the pasuk have to tell us that the leitz doesn't listen to rebuke? This is part of his very definition! There are many pesukim in Mishlei which highlight this quality of the leitz: "One who chastises the leitz acquires shame for himself" (Mishlei 9:7), "Do not rebuke a leitz, lest he hate you" (ibid 9:8), "A leitz does not like being reproved; he will not go to the wise" (ibid. 15:12), and more. What does our pasuk add? 
3. Why does the pasuk us the word "gaarah" for rebuke? Usually I'm not bothered by such nuances in the words, but in this case, it's strange. Ordinarily, Mishlei would use more conventional terms, like "tochahah" or "mussar" or even "eitzah." The weird thing about the word "gaarah" is that it means "rebuke" but it also means "shouting" or "shrieking." What does this mean? 

Four-sentence Summary of the Main Idea

All human beings harbor a certain degree of resistance to authority. The ben chacham is able to rise above this resistance even when being disciplined by his father - the supreme psychological authority - and learn from what he has to offer. In contrast, the leitz's psychological resistance is so pronounced that he hears all rebuke as if the rebuker is yelling at him; consequently, his mind will be completely closed to criticism. The only way to get through to the leitz is to bypass his psychological resistance and get him to see the consequences of his actions with his own mind; as long as these consequences are framed in practical terms rather than superego terms (e.g. "bad" "sinful" "evil"), there is at least a remote possibility that he will listen.