Discussions

I like reading the different discussions that come up here on eBrandon. They are funny, interesting, and informative. But as I've been reading some of the current threads a thought occured to me. Or rather, a question.  
Why is it that so many of us are unable to express our opinions in a positive, constructive manner? Why are so many of these discussions laced with anger, prejudice, resentment, judgement, defensiveness, condesending language, and the refusal by so many to earnestly give another opinion the thought it deserves.  
Why is it, eBrandonites, that as mature adults, we sometimes have so much trouble expressing ourselves in a positive manner??? And why are we so unwilling to chance a new perspective???