Keep Your Beliefs Cruxy

My guess is that two things were going on (this is based in part on observing some recent doublecruxes at the Intellectual Internet Infrastructure Retreat [LW(p) · GW(p)], where I had a similar sense of "This doesn't seem especially different or more effective from 'just talking.'")

• Deep disagreements take way more than an hour. An hour is when both parties share most of the same ontologies and worldviews, there's just one subset of their model that's different.
• Related to the pet-peeve I commented on my previous post [? · GW]: people colloquially use the term 'doublecrux' to refer to the entire disagreement process. But the process usually starts with something I'd describe as 'model sharing', which is basically regular conversation that gets people up to speed on how they're thinking about the problem. Only after that's finished does it make sense to do "official doublecrux moves." This is particularly confusing when people set up recorded one-hour doublecruxes for disagreements that are realistically more like 12 hours, the first 3 of which are just model sharing.
• (this is a particular challenge for educating people about doublecrux. "Real" doublecrux just doesn't lend itself to clean examples that work well pedagogically)

The main observation that I'd use to distinguish 'doublecrux' from 'disagreement' is whether the participants are saying things like 'hmm. would that actually change my mind?', and whether they're talking about events they could imagine observing. (if both participants are skilled at doublecrux, this might be going on under-the-hood rather than spoken aloud, but you should at least hear them say words about observations that might shift their perspective)

When I say "doublecrux is the fastest way for two people to resolve disagreement", I'm making a strong-confidence claim, a medium claim, and a weak claim:

• Strong Claim: the fastest way for two people to resolve disagreements is to focus directly on what would change their mind, without regard for legibility to anyone else, or PR, or whatnot.
• Medium claim: The most robust way to keep this aligned with truth, rather than accidentally aligned with 'who is more socially dominant or authoritative or has a more compelling narrative or something', is to focus on empirical observations.
• Weak claim: the particular operationalization of doublecrux (looking for cruxes, looking for common cruxes, and then looking for empirical tests to run) is the best way to formalize this.

I believe all three claims. Perhaps ironically (and maybe this should be a red flag that makes me reconsider?), I believe the first claim the strongest for first-principles reasons. It just seems like "well, obviously if two people want to resolve their disagreement the fastest, they'll want to focus on what would actually change their mind.' I can imagine it turning out to be that people's psychological is weird and confusing such that this isn't true, but it'd be very surprising to me.

I think it's worth pointing out that there's nothing all that special about double crux if you're used to having discussions with people on the order of being professional philosophers; double crux is just a fancy name for what I would have previously called arguing in good faith. It is special though in that many people are neither naturally shaped such that they naturally disagree with others that way or have no been trained in the method, so giving it a special name and teaching it as a technique seems worthwhile since the alternative is you know there is a "right" way to argue that converges towards truth and a "wrong" way that doesn't and teaching people to do the move where they find the beliefs their ideas hinge on and analyze that hinge in a way that might alter it and thus the entire belief network is hard if you can't precisely describe how to do it.

I feel quite confident that you already know the skill being called double crux based on the conversations I've seen you participate in LW, though I also understand how it can look like there is some "magic" in the technique you're not getting because it feels pretty magical if you learn it late in life and are then like "oh, that's why all my disagreements never go anywhere".

Nod. I had meant the first link in the post to establish the context (I had attempted to write the post I linked to there as a good first-introduction to doublecrux, which in turn linked to the original document you linked to here. But, seems good to go ahead and link directly here too.

I was the friend in the story. Here's something which might be part of the picture of resolving this. I had an argument for wanting a party with the structure: A -> B, I also believed A, so I concluded B was true.

We could have double-cruxed over the entailment A -> B or if you already agreed to that, then over the truth of A, where A can be made up of many propositions.

The shift is perhaps going from the double-crux being about a conclusion of what action to take to being about whether an argument (entailment) plus its premises are true. These of course are my cruxes once/if I can uncover my beliefs to this structure (which seems like you should be able to).

Overall though, I'm a bit confused by "negatives" and "null options". In all cases you're arguing about how the world is. You can just always say "what is my crux the world is not that way?", "what are the positive beliefs that cause me to think the world is not the way my interlocutor does?"

Alas, double-cruxing is a two-person game; you can't make another person do it, you can only do it with someone who genuinely wants to. For everyone else, the best related trick I know is nonviolent communication.

Pedantic correction: We didn't spend 4 weeks on it; while 4 weeks did pass, there was a lot of other stuff going on during that interval.

To me that n choose 2 is more of an upper bound. If each 1-on-1 didn't hear each other and they were not ordered then the time to do those would be the same as randomly picking people to discuss. But in a group discussion the discussion can hear each others. In a simple case where there are only 2 true factions but each faction has 50 members you could have the whole group crux if 1 member from different factions cruxed and others listened and the chosen ones were perfectly representative of their factions. To the extent there is faction internal strife you can't reuse per se the previous discussion. The least copyfriendly case is when everything needs to be done fresh for each member in which case it doesn' t matter if 1-on-1 discussion do not hear the group discussion.

On one hand adding additonal participant means it's another dice throw from what random position they start from which can be in additional dimensions not yet exhibited. On the other hand each thing said can be listened multiple times in the same time frame (or reverse each listener can only receive 1/n amount of talk that is relevant to their beliefs).

Conjecture: The amount of time it takes to use double crux as a group can be lower bounded by the amount of time it takes every pair to double crux. If we assume the amount of time for every pair is the same (which it isn't), and call that amount of time t, then the lower bound is t*n(n-1)/2. (Because n choose 2 = n(n-1)/2.)

"How much time it'd take to pairwise doublecrux" seems like a useful detail, but doesn't seem like either an upper or lower bound. (I think it works as "this is approximately how long you should expect things to take on average", with some debates taking longer and some shorter)

Things might take longer, because maybe if everyone pairwise doublecruxes, each pair ends up disagreeing with other pairs due to idiosyncratic beliefs or personal-history that other pairs didn't share.

Things might take less time, because multiple people in the group might share enough beliefs that they can functionally share updates.

i.e. if Alice, Bob, Catherine and Doug all doublecrux, it might be that once Alice and Bob have doublecruxed, Alice can easily say to Catherine (who has a similar worldview 'Bob explained this to me, it works like X', where X uses some shorthand that Alice and Catherine already share.

There's also the possibility that it turns out to be a) useful for some people, but not others, b) useful**, but for something other than double crux*, c) this is an area where gains take time - perhaps past some threshold of low hanging fruit.

Yup. The cruxes I listed there would not shift me to "this is useless", but they would shift me to "I retract my blanket endorsement of this strategy for everyone who reads LessWrong."