How to argue well

Ranil and Dave lament the impasse in the great development debates.

Here's some nice ideas from Scott Berkun, taken from his rules for discussing politics with friends (without ending up hating each other)

What would convince you that you are wrong? If you have no answer to this question, you haven’t thought very hard about your position. There must be some set of new facts or conditions in the world that would make you take a different point of view, even if they are unlikely or improbable. It’s not much fun to talk to people who have complete certainty that they’re right about everything.