I've wondered this about myself often too. It's hard to explain because I know most people aren't like this. Most people are just looking to 'win' arguments, show off their knowledge, or whatevber. Like I said before, this is not an ego thing for me. It's not like I sit here thinking "Hahaha, look how I am mentally dominating you all". Like I told Tathanen in either that post, or one above it, I try to hunt for the truth of things, for lack of a better word. An argument, to me, isn't a fight, it's an exploration.
To discern truth, I use argumentative techniques and engage with others. But I hunt it for myself. If I go into a conversation, feel I've completely refuted someone's arguments, but learned nothing, I guess that's good practice, but it's mostly just a matter of keeping my wits sharp, not gaining anything. What I look for is perspectives I haven't considered, and then I put pressure on them to see if they crack. If they don't, that's when I get really happy. It doesn't matter to me whether or not I agree with it, it's a new way of understanding things, and it works. It's obviously a case of diminishing returns, but you eventually find something new, or even rediscover a perspective you've forgotten or just leaned too far away from. I don't care about 'winning' a debate, I care about finding out how things actually are, how people think, etc. That's why I read fiction too.
