David Matolcsi

• David Matolcsi 9 Jun 2026 15:44 UTC

  2 points

  0

  in reply to: Bruce Middleton’s comment on: Clar­ify­ing the Dar­wi­nian Honeymoon

  I think 2.6 billion people in the US would probably do fine. There is just a lot of land to be farmed in the US. It’s not even clear to me if per capita wealth would be lower or higher if the US had 2.6 billion people—my guess is higher. So I think the miracle leading to a wealthier society today really was economic and technological, and not contraception.

• David Matolcsi 9 Jun 2026 15:21 UTC

  2 points

  0

  in reply to: David Matolcsi’s comment on: Lukas Fin­nve­den’s Shortform

  Ok, in my eventual formulation, I’m not actually relying on moral parliaments. However, I will note that in your and Paul’s original formulation of the double-updating paradox, you were writing about bets where your utility is linear in money (e.g. small amounts of money donated to charity).

  Here you write “if you ever get evidence that a decision is high-stakes enough and universal enough throughout the universe, EDT may well recommend that you make an exception for it and do a proper double-update on it, which seems bad”. At the point where you are making very high-stakes and universally applicable decisions, I’m no longer convinced you get linearity, and I might bite the bullet that there might be some bets you don’t want to engage in on either side, or the paradox fails in other ways.
  
  Altogether, I still think that my previous answer basically dissolves this paradox.

  I think in both cases the decision-correlational reference class you should take into account is not just you learning T1 is true and you learning T2 is true within this particular experiment. It’s every instance across the multiverse where beings similar to you need to make bets about questions they have no clue about. Taking all these correlations into account, the correct thing to do is to bet with 50-50.
  

• David Matolcsi 9 Jun 2026 15:08 UTC

  4 points

  2

  in reply to: Kaarel’s comment on: Prob­a­bil­ities are not the right concept

  Thanks! The statue example seems right, in that case the shortest description really doesn’t point to something I would call an observer that can be called me, since it points to the inanimate inscription on the statue.

  Anyway, as you can see from my later posts, I’m generally not in favor of following Solomonoff induction off the cliff, and I think we will probably need to use more qualitative value judgments in our weightings.

• David Matolcsi 8 Jun 2026 8:29 UTC

  2 points

  0

  in reply to: leogao’s comment on: leogao’s Shortform

  I don’t think AI water usage fits the pattern. People keep repeating the line “AI uses a lot of water”, and making political cartoons about AI slurping up all the water in the world, but I don’t remember anyone ever arguing for it being true.
  
  This is in contrast to religion, price fixing and possibility of AGI, where you can in fact find smart people making long and complicated arguments on both sides.

• David Matolcsi 31 May 2026 6:49 UTC

  2 points

  0

  in reply to: Elias Schmied’s comment on: In­finite ethics and UDASSA

  Thanks! Here is the third and final post.

An at­tempted syn­the­sis on prob­a­bil­ities and infinities

• David Matolcsi 30 May 2026 8:56 UTC

  3 points

  0

  in reply to: kbear’s comment on: In­finite ethics and UDASSA

  To be clear, I’m not really endorsing this logic, and I will write more in my next post about how to compare the values of smaller and bigger universes. But I do think that naive expected value calculation leads to weird places with infinities, so this is a good motivating question for developing better theories.

• David Matolcsi 29 May 2026 12:02 UTC

  2 points

  0

  in reply to: Kaarel’s comment on: Prob­a­bil­ities are not the right concept

  I guess this is largely a semantic question at this point. Originally, I wrote “the laws of nature”, and not “our laws of nature”. But even if you say “our world”, arguably that still works: if I’m living on a computer run by aliens, then arguably the base reality where the computer sits is my world. You can point to me by pointing at the laws of the base reality world and pointing at my computer within it.

  I’m interested though why you believe there are shorter good predictors than world + pointer. I agree it’s possible, I just can’t think of one. How would they look like?

• David Matolcsi 29 May 2026 5:59 UTC

  2 points

  0

  in reply to: Caleb Biddulph’s comment on: Prob­a­bil­ities are not the right concept

  Thank you! I edited the post with the link.

• David Matolcsi 29 May 2026 5:50 UTC

  4 points

  0

  in reply to: Kaarel’s comment on: Prob­a­bil­ities are not the right concept

  Yes, I absolutely think that Solomonoff induction is probably malign. But I understood that to also work through a world + pointer framework. There is someone in our world making a very important decision about the future, based on a prediction they are making using Solomonoff induction. The pointer to their moment is not particularly simple. Alines in another world run a short solipsistic simulation of this entity making the decision. They run the simulation in a particularly easy-to-point-to sport, or they run many copies of the simulation in random places. Thereby the aliens simulation-capture the predictor.
  https://​​www.lesswrong.com/​​posts/​​KSdqxrrEootGSpKKE/​​the-solomonoff-prior-is-malign-is-a-special-case-of-a
  Is your understanding different?

• David Matolcsi 28 May 2026 19:14 UTC

  4 points

  2

  in reply to: Kaarel’s comment on: In­finite ethics and UDASSA

  Great point, I haven’t thought of this. I will edit the post, referencing you.
  
  I do think that the constant helps a lot: we now moved from “you are overwhelmingly likely to be a BB” to “BB version of you have 2^-20 weight, so are basically negligible given that you can’t do much for them anyway”.
  
  I still think that there is something unreasonable about giving 2^-20 weight to BBs based on this logic—I think the weirdness is pretty similar to the World-summoning by writing thought experiment. I think I just want to reject this type of logic by fiat under my non-realist epistemology that I write about at the end of the post.

• David Matolcsi 28 May 2026 19:09 UTC

  4 points

  0

  in reply to: Kaarel’s comment on: Prob­a­bil­ities are not the right concept

  Maybe I’m missing something, but yes, I think “the laws of nature plus a pointer to my location” is a good description. Why would that be so bizarre? It doesn’t seem crazy to define the laws of nature, then define the concept of temperature, the concept of distance and the concept of time, then define the coldest spot in the universe’s history (which is, iirc, to the best of our knowledge, human-created), then specify a spot X years and Y kilometers distance from that experiment, and that points out me sitting here right now. (Assuming that we never create something colder in the future.) I think something like that is what this description of Solomonoff induction would do?
  
  I agree that the quantum multiverse complicates things, I am writing about that in my next post.

  ---
  
  In my head, there are two definitions of Solomonoff induction: one is where you assume that your inputs so far has been produced by a simple program. My impression is that that’s the definition I usually encountered in the Bay Area folklore, and for example I think that’s the definition Joe Carlsmith is using in his post on UDASSA. So that’s the version I reference in this post.
  
  The other definition, where you assume you are sampled from an easy-to-describe random distribution was something I don’t remember encountering, and came up with it as an exciting new thing. I write about it in my next post. https://​​www.lesswrong.com/​​posts/​​zvqodicK8q2SNAZkd/​​infinite-ethics-and-udassa#Resolution___Solomonoff_over_distributions
  
  I think that’s probably equivalent to what you describe as “the UTM version of Solomonoff”. As I say in that post, it looks like this is maybe the more standard version in academia, and in retrospect maybe I should have started with that version in the first post.
  
  But I don’t think the distinction between the two versions are a crux for any of my objections, except for objection 3, which I already flag in the first post that it will be relatively easy to resolve with a new formalism.
  
  (It’s possible I’m still missing something here—as you might be able to tell, I don’t have that much background in the mathematical study of Solomonoff-induction.)

In­finite ethics and UDASSA

• David Matolcsi 24 May 2026 5:36 UTC

  6 points

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  in reply to: Eye You’s comment on: Prob­a­bil­ities are not the right concept

  I like my strategy of silently amending “assuming a materialistic world-view and not being in a sim” to all mundwne questions. I think that makes it possible to non-misleadingly communicate about the probability of AI takeover.

  (This is assuming that you agree that you should mostly act as if you were in a materialistic non-sim world.)

• David Matolcsi 24 May 2026 5:26 UTC

  2 points

  0

  in reply to: Noosphere89’s comment on: Prob­a­bil­ities are not the right concept

  Yes, I will make this point in my next post. (I’m not sure though if probabilities being caring measures is a necessary consequence of UDT. I thought this was a different axis.)

Prob­a­bil­ities are not the right concept

• David Matolcsi 18 May 2026 21:00 UTC

  6 points

  0

  in reply to: Garrett Baker’s comment on: A rel­a­tively brief ex­pla­na­tion of Boltz­mann Brains

  Ok, but are there specific chapters or pages he or others could link to? Linking to long novels is not very useful.

• David Matolcsi 18 May 2026 17:21 UTC

  7 points

  2

  in reply to: Eliezer Yudkowsky’s comment on: A rel­a­tively brief ex­pla­na­tion of Boltz­mann Brains

  Can you share a brief description or a link to your favored metaphysics of reality-fluid? I haven’t yet come across good write-ups on this topic.

• David Matolcsi 17 May 2026 7:00 UTC

  9 points

  −6

  in reply to: Eliezer Yudkowsky’s comment on: A rel­a­tively brief ex­pla­na­tion of Boltz­mann Brains

  I currently think I don’t actually need to explain what I see. What is the advantage of explaing it? Under normal circumstances, it’s useful to explain why I see e.g. the washing machine not working, because that gives me useful predictions about how the washing machine will behave in the future, and knowing that is useful for fulfiling my values.

  But if I have a preference like “life only has meaning if I win the lottery”, then I think it’s not action-relevant to find an explanation if I see myself winning. The day before the lottery, I was already only making follow-up plans for what to do if I win—that’s the only case where life has meaning. And it was not part of the plan to do an investigation of why I won the lottery—why would I want to waste my time on that? So when I actually win, I in fact don’t investigate it further.

  To be clear, I think that caring a lot about universes where you win the lottery, at the expense of other universes, is a very sillly moral belief. If someone held this belief, I would tell them to meditate a little and play with a toddler and imagine if they would really care less about her if she was living in a universe where they don’t win the lottery. But if they come back saying that they genuinely only care about lottery-winning universes, then I can’t argue with their utility function.

  I think having at least 0.1% of my caring allocated to short description-length space-time points is not that crazy of a moral belief. And once I have that, it’s reasonable to have a policy like “if I see an ordered world, I will act as if I was not a Boltzmann-brain, because these ordered situations are important for the 0.1% of my values, but are vanishingly rare and unimportant from the perspective of the 99.9%”.

  I now see an ordered world, so in accordance with this policy, I act as if I was not a Boltzmann-brain. Acting as if I was not a Boltzmann-brain includes not looking for mechanistic explanations for why I’m not one, so I don’t do that.

• David Matolcsi 16 May 2026 22:11 UTC

  13 points

  −3

  on: A rel­a­tively brief ex­pla­na­tion of Boltz­mann Brains

  or any metaphysics which says you can’t objectively answer the question “Which observer-moments exist or don’t exist /​ have more weight to them than other observer-moments?”

  Why can’t I say that there is no objective answer to which observer-moments exist more, but that I subjectively care more about the observer-moments that happen in mathematically simple universes, in simple-to-describe locations, like Scott Garrabrant describes in Preferences without Existence?
  
  In this ontology, “I expect that my brain won’t dissolve into chaos in the next moment” translates to “I will continue preparing dinner instead of meditating on the meaning of mortality, because preparing dinner helps the versions of me who live in simple locations, and meditating on mortality helps the Boltzmann-brain versions of me who are about to die, and I subjectively care more about the versions of me living in simple locations”.
  
  With some added caveats on what exactly I care about (I hope to publish a sequence of this soon), I find this view more appealing than assuming the existence of a reality fluid that makes some moments objectively more real than others.