Edit: wtf video appeared in my preview but not in actual post...sorry about that.
I touched on it last post, but people just are not made to debate or even argue in any constructive way it seems. Look at the legal system (and I'm talking about the US here because that's what I have experience with). It's designed to be an antagonistic system, with 2 sides debating the merits of their positions based on rules of logic and evidence-ideally. This is the true essence of debate. Two sides passionately advocate for their point of view using codified rules of logic, verified impartial evidence, and the whole matter is presided upon by an impartial party.
This artificial system evolved/was created because otherwise we'd be stuck in a situation like the above: just constant contrarian NO/YES battles with no real end or resolution of any import. An impartial judge is tasked with making sure the parties streamline their arguments, stay on topic, use evidence and logic appropriately, and to arbitrate minor decisions. In a debate like one you would participate in at school, this is what a moderator does. I'm not a big fan of emotional appeals during debate, but I also recognize that humans are emotional creatures and that every moment has some emotional content to it for us.
This emotional context is what makes a good debate so difficult. Conflict can be inspiring and enjoyable, but it's also somewhat against our nature. Generally, people want to get along. We're social animals. We want people to like us. Telling someone they are wrong, then spelling out how they are wrong is not how you go about making nice with others. Internally, conflict causes a biological stress response that gets you ready for action, the "fight or flight" response. The more worked up you get, the harder it is to function with your logical mind. Psychologically, conflict can be a threat to your ego. Most people like to think they are good, intelligent, reasonable, whatever other positive attributes you can think of. Being faced with an attack to your "rightness" throws you into a defensive mode. And what's worse about all of this is that it's discouraging to you admitting you are wrong because it will cause you to a)look foolish b) show you were wrong c) make you look weak d) make you look inconsistent.
So when you think about this, it's really amazing that we can ever accomplish anything. When I say this I mostly have politics and science in mind. However, with scientific debate there is a little more structure and the scientific community, and subgroups of specialities are pretty good at policing themselves. But with politics, look at what happens any time a politician changes their stance on anything. They become a "flip-flopper." This phrase defeated John Kerry, and has become a skillful political weapon to assassinate anyone who-for right or wrong reasons-decides to change. Why does change have to be so bad? Can we intellectualize away the stigma of "flip flopping?" We all know that circumstances can change. Why should we be locked into a single course of action forever? What's so wrong with growing?