Paul Graham: The truth is common property. You can’t distinguish your group by doing things that are rational, and believing things that are true. If you want to set yourself apart from other people, you have to do things that are arbitrary, and believe things that are false.
Sensible Person: That’s why groups are bad.
Post-Rationalist: Let’s get some false beliefs and arbitrary practices going!
Is “groups are bad” true? I think it might be false.
Groups are bad when and to the extent that they lead to this kind of behavior. It’s not inevitable, but it’s something to watch out for, and certainly shouldn’t be encouraged.
Consider: Doing arbitrary practices just because you’re a group is really pleasant and correct and creates feelings of deep continuity and humanity. Well, at least for some people.
You can’t distinguish your group by doing things that are rational, and believing things that are true.
If you can somehow finangle yourself into a situation where you do only things that are rational and believe only things that are true, you are a very distinct group separate from the rest of humanity as much as the communists, mormons or nascar fans are.