If I had to name a single reason why two wannabe rationalists wouldn't actually be able to agree in practice, it would be that, once you trace the argument to the meta-level where theoretically everything can be and must be resolved, the argument trails off into psychoanalysis and noise.
And if you look at what goes on in practice between two arguing rationalists, it would probably mostly be trading object-level arguments; and the most meta it would get is trying to convince the other person that you've already taken their object-level arguments into account.
If you consider most LWers "aspiring rationalists", the above should describe most of the disagreements, but somehow it does not seem so.
It would be a useful exercise if people picked a recent comment thread they have no stake in and analyzed the reasons for disagreement. Any takers?
Today's post, The Mechanics of Disagreement was originally published on 10 December 2008. A summary (taken from the LW wiki):
Discuss the post here (rather than in the comments to the original post).
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