I think this article on How to Disagree is a very helpful resource for keeping discussions on the internet productive:

http://www.paulgraham.com/disagree.html

From the article:

"Truly refuting something requires one to refute its central point, or at least one of them. And that means one has to commit explicitly to what the central point is. So a truly effective refutation would look like:

The author's main point seems to be x. As he says:
<quotation>
But this is wrong for the following reasons...

The quotation you point out as mistaken need not be the actual statement of the author's main point. It's enough to refute something it depends upon."

i disagree.. that's just stoopid talk.

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Ah. The article is a barebones summary of the rules of debating.

There is a widening gap between those who understand valid debating techniques and those who do not.

there is a big difference between debating and disagreeing.
in a debate, for instance, there are actual rules that must be followed so a "winner" can be declared.
in a disagreement, you just yell and get all huffy because the other person is to dimwitted to see how much more logical your view is.
i'm more of a diasgree-er than a debater, myself, but i don't yell. i've never been big on formalities.

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Whether or not the procedure of debating is used, there are still techniques that keep a disagreement on track.

Pointing out that someone is attacking the arguer and not the argument (ad hominem) is a good one.
Pointing out that "Oh, so you think citizens have the right to keep arms in their home. Kids live in those homes. You must think it's OK for kids to play with guns." is a straw man is another one.

Unfortunately that's only an effective refutation in your own mind, not in the mind of the person you're refuting, as he can just say "No, you're misunderstanding <author>, x isn't his point at all", at which time your carefully constructed refutation isn't a refutation at all.
This counter-technique is commonly employed by ATM proponentsl, which gives me the impression that the autor of the article hasn't tried much discussion with people with really different opinions.
He should try a couple of days in ATM.

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[deadpan] You know, all of these pointless arguments would end forever if you would all just admit I'm right while nodding at appropriate intervals. [/deadpan]

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We each have slightly different ways of debating (and disagreeing). But I do agree with the point quoted from the article, that a good oponent will try to find your main point, and debate that -- as opposed to getting all pedantic with semantics or side remarks, as often happens in message boards. A while ago I read somewhere (unfortunately I forgot where), about Karl Popper's style of debating, that rather than attacking the obvious weaknesses in the arguments of his opponents, he would focus on the strengths, interpreting them in the best possible light and even improving upon them, before endeavouring to refute them. I thought this was an admirable form of debating, though it's no doubt a difficult standard to keep. We're only human.

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