More like this/Less like this makes sense for top posts, but is it helpful for comments?

It's ok to keep an imperfect system - LW is nowhere near groupthink levels of subreddits or slashdot.

However - it seems to me that stealing HackerNews / Stackoverflow model of removing normal downvote, and keeping only upvote for comments (and report for spam/abuse, or possibly some highly restricted downvote for special situations only; or one which would count for a lot less than upvote) would reduce groupthink a lot, while keeping all major benefits of current system.

Other than "not fixing what ain't broken", are there any good reasons to keep downvote for comments? Low quality non-abusive coments will sink to the bottom just because of not getting upvotes, later reinforced by most people reading from highest rated first.

Disclaimers:

I'm obviously biased as a contrarian, and as someone who really likes reading a variety of contrarian opinions. I rarely bother posting comments saying that I totally agree with something. I occasionally send a private message with thanks when I read something particularly great, but I don't recall ever doing it here yet, even though a lot of posts were that kind of great.

And I fully admit that on several occasions I downvoted a good comment just because I though one below it was far better and deserving a lot of extra promotion. I always felt like I'm abusing the system this way. Is this common?

Agree here. In defense of LW I would say that this seems like a pretty generic feature across groups in general. I myself try to be careful about interpreting statements made by those with views that clash with my own charitably but don't know how well I succeed.

I don't consider LW particularly bad - it seems considerably saner than a typical internet forum of similar size. Level of drama seems a lot lower than is typical. Is my impression right that most of drama we get centers about obscure FAI stuff? I tend to ignore these posts unless I feel really bored. I've seen some drama about gender and politics, but honestly a lot less that these subject normally attract on other similar places.

A quick observation: Perfect Bayesian mind is impossible to actually build, that much we all know, and nobody cares.

But it's a lot worse - it is impossible even mathematically - even if we expected as little from it as consistently following the rule that P(b|a)=P(c|b)=100% implies P(c|a)=100% (without getting into choice of prior, infinite precision, transfinite induction, uncountable domains etc., merely the merest minimum still recognizable as Bayesian inference) over unbounded but finite chains of inference over countable set of statements, it can trivially solve the halting problem.

Yes, it will always tell you which theorem is true, and which is false, Goedel theorem be damned. It cannot say anything like P(Riemann hypothesis|basic math axioms)=50% as this automatically implies a violation of Bayes rule somewhere in the network (and there are no compartments to limit damage once it happens - the whole network becomes invalid).

Perfect Bayesian minds people here so willingly accepted as the gold standard of rationality are mathematically impossible, and there's no workaround, and no approximation that is of much use.

Ironically, perfect Bayesian inference systems works really well inside finite or highly regular compartments, with something else limiting its interactions with rest of the universe.

If you want an outside view argument that this is a serious problem, if Bayesian minds were so awesome, how is it that even in the very limited machine learning world, Bayesian-inspired systems are only one of many competing paradigms, better applicable to some compartments, not working well in others.

I realize that I just explicitly rejected one of the most basic premises accepted by pretty much everyone here, including me until recently. It surprised me that we were all falling for something as obvious retrospectively.

Robin Hanson's post on contrarians being wrong most of the time was amazingly accurate again. I'm still not sure which ideas I've came to believe that relied on perfect Bayesian minds being gold standard of rationality I'll need to reevaluate, but it doesn't bother me as much now that I fully accepted that compartmentalization is unavoidable, and a pretty good thing in practice.

I think there's a nice correspondence between outside view and set of preferred reference classes and Bayesian inference and set of preferred priors. Except outside view can be very easily extended to say "I don't know", estimate accuracy of itself as applied to different compartments, give more complex answers, evolve in time by reference classes formerly too small to be of any use now having enough data to return useful answers, and so on.

For very simple systems, these two should correspond to each other in a straightforward way. For complex systems, we have a choice of sometimes answering "I don't know" or being inconsistent.

I wanted to write this as a top level post, but "one of your most cherished beliefs is totally wrong, here's a sketch of mathematical proof" post would take a lot more effort to write well.

I tried a few extensions of Bayesian inference that I hoped would be able to deal with it, but this is really fundamental.

You can still use subjective Bayesian worldview - that P(Riemann hypothesis|basic math axioms)=50% is just your intuition. But you must accept that your probabilities can change with no new data, by just more thinking. This sort of Bayesian inference is just another tool of limited use, with biases, inconsistencies, and compartments protecting it from rest of the universe.

There is no gold standard of rationality. There simply isn't. I have a fall back position of outside view, otherwise it would be about as difficult to accept this as a Christian finally figuring out there is no God, but still wanting to keep the good parts of his or her faith.

Would anyone be willing to write a top level post out of my comment? You'll either be richly rewarded by a lot of karma, or we'll both be banned.

I'm trying to write up something on this without actually giving readers fear of ideas. I think I could actually scare the crap out of people pretty effectively, but, ah. (This is why it's been cooking for two months and is still a Google doc of inchoate scribbles.)

I enjoy reading disagreements most

Does it seem to you as well that removing downvote for comments (keeping report for spam and other total garbage etc.) would result in more of this? Hacker News seems to be doing a lot better than subreddits of similar size, and this seems like the main structural difference between them.

Sure: compartmentalisation is clearly an intellectual sin

Compartmentalisation is an "intellectual sin" in certain idealized models of reasoning. Outside views says that not only 100% of human level intelligences in the universe, but 100% of thing even remotely intelligent-ish were messy systems that used compartmentalisation as one of basic building blocks, and 0% were implementations of these idealized models - and that in spite of many decades of hard effort, and a lot of ridiculous optimism.

So by outside view the only conclusion I see is that models condemning compertmentalisation are all conclusively proven wrong, and nothing they say about actual intelligent beings is relevant.

reality is all one piece

And yet we our organize knowledge about reality into extremely complicated system of compartments.

Attempts at abandoning that and creating one theory of everything like objectivism (Ayn Rand famously had an opinion about absolutely everything, no disagreements allowed) are disastrous.

but we're running on corrupt hardware so due caution applies.

I don't think our hardware is meaningfully "corrupt". All thinking hardware ever made and likely to be made must take appropriate trade-offs and use appropriate heuristics. Ours seems to be pretty good most of the time when it matters. Shockingly good. Expecting some ideal reasoner that has no constraints is not only physically impossible, it's not even mathematically possible by Rice Theorem etc.

Compertmentalisation is one of the most basic techniques for efficient reasoning with limited resources - otherwise complexity explodes far more than linearly, and plenty of ideas that made a lot of sense in old context are now transplanted to another context where they're harmful.

The hardware stays what it was and it was already pretty much fully utilized, so to deal with this extra complexity model needs to be either prunned of a lot of detail mind could otherwise manage just fine, and/or other heuristics and shortcuts, possibly with far worse consequences need to be empleyed a lot more aggressively.

I like this pro-compartmentalization theory, but it is primarily experience which convinces me that abandoning compartmentalization is dangerous and rarely leads to anything good.