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A Brief Explanation of Greg Egan’s Dust Theory
- tomrod 6y agoInteresting article! As linked in the article, Egan posted some FAQ/counterarguments for issues raised here: https://www.gregegan.net/PERMUTATION/FAQ/FAQ.html https://www.gregegan.net/PERMUTATION/FAQ/FAQ.html
- croissants 6y agoNice, IMO this (short) FAQ has a lot more useful info than the featured article. His claim at the end that creating intelligent life through evolution is deeply immoral confuses me, though -- by all accounts, we arose through that process, and relatively few people seem bothered by it.
- c1ccccc1 6y agoPeople are probably less bothered by it because it happened so long ago, and was not perpetrated by any kind of thinking agent. The process of evolution definitely entails a lot of suffering, though. Consider almost any attribute of modern day humans, fear of heights, say. Millions of creatures had to fall to their deaths (many of them very similar to modern humans) to etch that fear of heights into the surviving generations. Or take the gag reflex: many deaths by choking. The immune system: billions of deaths by disease and infection. It would certainly be immoral to inflict such things, if you had the ability to prevent them.
- athriren 6y agoimagine a person gets cancer and dies. this is, by itself and with no context, an act that has no moral component—it just happened. now imagine YOU gave the person cancer. this difference is the difference between the presumably undirected evolution that led to us, and the sort of fucking around with actual living things we would need to do to direct evolution ourselves.
- Sharlin 6y agoRelatively few people have thought through the moral implications of a few hundred million years of nature red in tooth and claw, so that's not exactly surprising. After all, relatively few people have even thought through the moral implications of the fact that they can purchase abundant cheap meat from any supermarket. The thought of starting a simulation that has even a slight chance of creating entities capable of suffering should give anyone a major pause.
- codeulike 6y agoHe means that deliberately setting up a synthetic evolution process to generate intelligent life would be immoral. His short story Crystal Nights deals with this. Its a corker of a story. https://www.gregegan.net/MISC/CRYSTAL/Crystal.html https://www.gregegan.net/MISC/CRYSTAL/Crystal.html “What created the only example of consciousness we know of?” Daniel asked. “Evolution.” “Exactly. But I don’t want to wait three billion years, so I need to make the selection process a great deal more refined, and the sources of variation more targeted.” Julie digested this. “You want to try to evolve true AI? Conscious, human-level AI?” “Yes.” Daniel saw her mouth tightening, saw her struggling to measure her words before speaking. “With respect,” she said, “I don’t think you’ve thought that through.” “On the contrary,” Daniel assured her. “I’ve been planning this for twenty years.” “Evolution,” she said, “is about failure and death. Do you have any idea how many sentient creatures lived and died along the way to Homo sapiens? How much suffering was involved?”
- domenicd 6y agoA while ago I wrote up my own take, inspired largely by Permutation City but also by Tegmark's mathematical universe hypothesis: https://blog.domenic.me/mathematical-consciousness/ https://blog.domenic.me/mathematical-consciousness/ To me this line of thinking is very attractive. As someone who has been a mathematical Platonist forever, this gives a very satisfying answer to big questions like "why is there something instead of nothing" and "why is our universe so perfectly described by mathematics".
- GeekyBear 6y ago> Permutation City I haven't read that book since the early 90's but it dealt with ideas that have really stuck in my mind.
- croissants 6y agoThe main detail I remember from that book is that credit card companies would track whoever you dined with at a restaurant and then serve you ads featuring computer-generated people who resembled those people to manipulate you into trust. Pretty ahead of its time for 1994!
- GeekyBear 6y agoAt the time, using computational chemistry to simulate an entire living, evolving life form was just a mind blowing idea.
- JanSt 6y ago> Let’s consider what this simulation really is: a program, which generates a series of (very long) numbers. Each number represents the state of the computer’s memory at that point in the simulation. A projection like that seems very likely to break consciousness. Writing down the state of a computer onto a paper does not allow the paper to continue the computation.
- TheOtherHobbes 6y agoOur universe isn't perfectly described by mathematics. Parts of our universe can be described by mathematics on limited timescales while also assuming inherent randomness. Math can't even predict the fate of the solar system out to infinity. Planetary systems aren't unconditionally stable, and the effects of limited precision - presumably relevant to any hypothesis of computability - make very long term predictions not just unreliable, but impossible. This pretty much kills Tegmark's thought experiment, which is in any case a perfect example of begging the question - in spite of the increasing improbability of the examples. Platonists need to explain if they believe that consciousness is possible on clockwork hardware. If Platonists actually believe that, they may as well dismiss everything that's happened in science since the days of Newton, because that's a very extraordinary claim with absolutely no evidence to support it.
- geuis 6y agoI’ll take this one. Can someone provide some background as to exactly what is being discussed here?
- db48x 6y agoA major plot point and thematic element from a novel by Greg Egan called Permutation City.
- Flow 6y agoWould you consider this to be a spoiler for the book? I've not read my copy yet.
- db48x 6y agoYou probably won't understand this brief "explanation" until after you read the book. It's brief largely because it assumes that you know at least the events in the book, even if you couldn't follow the definitions and other exposition.
- j-pb 6y agoI don't know the original theory, but this explanation is brief to the point where it's nonsensical.
- boxed 6y agoMight be because the entire thing is nonsense. Entropy shoots a hole in the entire thing as far as I can tell. The problem is that the information can never be retrieved, so if it exists or not is really pointless.
- xwdv 6y agoIf you are the information though then you have retrieved it.
- boxed 6y agoNot really. Brains don't exist and cannot exist without a medium to work in. It's the old idea that we have souls that are independent from our bodies and underlying reality. This is nonsense.
- j-pb 6y agoYeah the whole thing is also way to handwavy when it comes to computational complexity of the encodings. It also somehow simultaneously assumes the church turing thesis, the existence of non computable reals and arbitrary functions over them at the same time...
- sxp 6y agoThis article doesn't actually explain Dust Theory to someone who hasn't read the book. I haven't found a good standalone explanation of the theory that explains it in a compact manner so my recommendation to people is to read the book. Permutation City is among my top 5 favorite books because I found Dust Theory so mind blowingly amazing from a philosophical standpoint. I haven't seen it discussed elsewhere outside the lesswrong.com forums (which are famous for creating Roko's Basilisk). It's only $3 on Amazon so it's worth picking up if you're a fan of hard sci-fi that gets into the philosophy of uploading: https://www.amazon.com/Permutation-City-Greg-Egan-ebook/dp/B00FDWCPV2 https://www.amazon.com/Permutation-City-Greg-Egan-ebook/dp/B... Dust Theory also provides an interesting option for people who want to achieve True Immortality. That is, immortality that can survive the heat death of the universe without violating the First or Second Laws of Thermodynamics. It also provides a hard sci-fi version of the concept of Subliming from Iain Banks' Culture novels where a civilization leaves this universe once they become sufficiently advanced. (Sublimation in the Culture books is similar to Ascension in the Stargate universe or Transcendence in Babylon 5.)
- db48x 6y agoYou'd probably like Neal Stephenson's Anathem. It's a Hemn Space argument.
- foobarbecue 6y agoIs that the one that had hundreds of pages of monks hanging around at the beginning? I got bored and couldn't make it through
- codethief 6y agoHe lost me right in the second paragraph: > Because computation is sort of subjective, just a set of relations that can be usefully interpreted as representing a function, this seems to imply that the function you identify with can be interpreted as being simulated by any sufficiently complex set of relations. Can anyone explain? I'm already struggling with the premise: Why should computation be subjective in the first place?
- tgv 6y agoAnd why would "sort of" subjectivity be sufficient for simulation? The only interpretation is that the author uses the word subjective to mean "a set of relations". It doesn't sound like math, more like pseudo-philosophical sci-fi. It also seems to assume that simulation of physical processes can be highly accurate and efficient, and that the function that represents "I" doesn't interact with the environment.
- throwaway_pdp09 6y agoExactly what I was going to quote, with a big fat 'wot?' to follow. Edit: I think we're being trolled by a text generator, see my other comment.
- db48x 6y agoHe states it in the previous sentence: > If you think experience is simulatable, [and] you buy computational or “patternist” theories of identity… Basically, the inner experience of any sapient computation (aka "person") is subjective.
- codethief 6y agoI would counter that by saying that: 1) this has nothing to do with computation. 2) my subjective experience is objectively there. No one questions what I am thinking. (That is, no one else looks inside my brain and claims: This is not what your thinking!) My thoughts might be my own personal view and differ from other people's thoughts but their existence is not up for debate.
- throwaway_pdp09 6y agoLooking at other stuff ISTM this is generated by one of them newfangled GPT3 things or whatever: "Nonetheless, It is because of my faith in science and its processes that I have always been of the opinion that the state pension, though grisly from a naive “one-worlder” perspective is actually a remarkably humane, efficient and (dare I say) generous social program." (https://cephalopods.blog/ https://cephalopods.blog/) and if you look at the home link https://cephalopods.blog/about/ https://cephalopods.blog/about/ anyone else think that looks like a generated face?
- codethief 6y ago> and if you look at the home link https://cephalopods.blog/about/ https://cephalopods.blog/about/ anyone else think that looks like a generated face? More importantly, it's a new face every time you reload the page.
- throwaway_pdp09 6y agoSo it is! Well spotted. I think you've proven it.
- codethief 6y agoNot sure I'd consider this a proof. Maybe it's just some weird dude :)
- codethief 6y agoCan anyone with GPT-3 beta access ask GPT-3 to give a summary of "Permutation City"? Given impressive examples like this one[0], I think GPT-3 might do better. [0] https://twitter.com/paraschopra/status/1284423233047900161 https://twitter.com/paraschopra/status/1284423233047900161
- throwaway_pdp09 6y agoYou call that roundabout word-salad concoction impressive?
- josh_fyi 6y agoI'd like to see more of this. Egan's work got more mathematical and harder to understand as the years went by. Not that I'd want him to dumb it down, but explanations are appreciated.
- MiroF 6y ago> This is sort of like the Boltzmann brain idea but even worse because it applies to any set of relations. According to Egan’s argument all possible experiences that can be computed by any sufficiently complex set of relations are in fact computed by them. This idea seems identical to the Boltzmann brain hypothesis and I don't understand how this paragraph differentiates it at all.
- ardy42 6y ago>> This is sort of like the Boltzmann brain idea but even worse because it applies to any set of relations. According to Egan’s argument all possible experiences that can be computed by any sufficiently complex set of relations are in fact computed by them. > This idea seems identical to the Boltzmann brain hypothesis and I don't understand how this paragraph differentiates it at all. I don't claim to totally understand this, but my impression is "Dust Theory" implies that the mind is more frequently simulated than in "Boltzmann brain" theory. IIRC, the latter imagines a literally brain being formed briefly out of matter.
- MiroF 6y ago> IIRC, the latter imagines a literally brain being formed briefly out of matter. I see. FWIW I think that is a very narrow reading of the Boltzmann brain hypothesis and while it may have been true to when it was first presented, I think the general "brain as abstract relations that can be simulated by physical systems" Boltzmann brain is what most contemporary cosmologists are talking about.
- aaron-santos 6y agoThe article really ought to close the loop by tying it back to the final 10% of the book. The big point in the book is that you can craft arbitrary surjections and have an infinite set of justifications for your subjective experience. A physical substrate is just as good as a computational/mathematical substrate. In this sense you can bootstrap your simulated existence into the immortal world of forms.
- croissants 6y agoThe part I don't understand about this, which is the same as the part I don't understand about dust theory, is that it seems to ignore the distinction between an abstract representation of an object and the object itself. By the logic of dust theory, I can walk into a bank and say "give me the money, or else I'll throw this handful of sand into the air, and it might encode a universe where you're tortured for a billion years!"
- aaron-santos 6y agoYou're right. To which the teller can reply, "I've crafted an encoding where you are tortured for billions of years." The idea is more about swapping out the substrate of your current subjective experience than creating a new encoding of your current universe. The book has the convient liberty of actually jumping between simulations/encodings to illustrate this, but it's ancillary to the main idea.
- namanyayg 6y agoA version of the banker in the "real" world will continue to exist, and the sand you throw might also encode a virtual copy of the banker later. If the sand flies just right, the copy might feel that it actually arose into it's tortorous existence because of your action of throwing the sand. In that case, the copy feels pain. The original banker continues existing unaffected (and calls the cops).
- xwdv 6y agoI think I can somewhat grasp what is being explained but maybe not really. As a thought experiment, if you had a screen of fixed resolution that displayed random color pixels, given an infinite amount of time, you could watch an entire specific movie (along with every other image), perhaps in random order, but from the movie's perspective if it were conscious it would not be aware of whatever order it's playing in, it would just perceive itself to be going forward I guess. The movie itself is like a function that displays an image as a function of time. So I guess they're saying consciousness in Dust Theory could be like that? What we perceive as a conscious moment is a brief output of random noise for a random timestamp?
- finm 6y agoThis reminds me of David Chalmers' 'Does a Rock Implement Every Finite-State Automaton'? http://consc.net/papers/rock.html http://consc.net/papers/rock.html
- layoutIfNeeded 6y agohttps://xkcd.com/505/ https://xkcd.com/505/
- canjobear 6y agoVery interesting to think about. Here's my interpretation of the argument: Suppose you have some system X whose dynamics are those of conscious agents in a world. For example, maybe X is the real world. Suppose that the agents in X really experience consciousness. Now suppose we apply some one-to-one function f to X, yielding Y = f(X). Then Y contains all the same information as X. So who's to say that the agents in X have consciousness but the agents in Y don't? Now by an inverse argument, suppose you randomly encounter some blob of random dust, Z. Then you can always come up with a one-to-one function g mapping Z to X, X = g(Z). So apparently the dust Z already contained all the conscious agents in the universe. Conclusion: The conscious experiences of all agents are present in all sufficiently complex blobs of random dust and all sufficiently complex networks of mathematical relations. One issue with this argument that hasn't been brought up yet is Kolmogorov complexity. Must random blobs of dust Z will be algorithmically random, not containing any real structure. In that case, the complexity of the function g that decodes Z into X will have to be huge. Essentially, the decoding function g itself will have to contain all the information that eventually ends up in X. So the information about conscious agents isn't really in the dust Z, it's in the decoder g.
- ajconway 6y agoIf you believe in mathematical realism than the fact that there surely exists a mapping between a random set of data and a simulation with conscious agents in it, that should be enough.
- chr1 6y agoIt's not enough if the mapping function does not use the information from the random set. For instance it is easy to construct a mapping from ordered digits of pi to ordered letters of your comment, but all of the information of your comment will be in the mapping.
- canjobear 6y agoExactly. The mapping function is almost always essentially a lookup table where you look up a dust configuration and get out a real-world configuration. The fact that you can construct this mapping doesn't mean much IMO.
- KerrickStaley 6y agoHere is an explanation of Dust Theory from Wikipedia: "[Dust theory states that] there is no difference, even in principle, between physics and mathematics, and that all mathematically possible structures exist, among them our physics and therefore our spacetime...The dust theory implies that all possible universes exist and are equally real, emerging spontaneously from their own mathematical self-consistency." I think this does a pretty good job of summarizing the concept: the universe is simulatable, but there is nothing doing the simulation; it just exists as a pure mathematical object. All other possible universes that are simulatable (i.e. follow some mathematical model) are equally as real as ours.
- echelon 6y agoSo this is some kind of fancy many worlds theory? Except instead of branching on outcomes, we simply fill up possibility space with everything conceivable?
- KerrickStaley 6y agoYes, the assertion (as I understand it) is that not only do different branches of our own world exist, but so also do all other mathematically consistent universes, even if they follow different rules of physics.
- pbhjpbhj 6y agoNot familiar with the concept, but how does it square with Godels Incompleteness theory, is any mathematical universe even possible?
- drdeca 6y agoThere is no conflict. An antidote to common misunderstandings of Gödel’s incompleteness theorems may be to understand Gödel’s completeness theorem.
- a1369209993 6y agoThe closest GIT gets to being relevant is that some mathematical universes exist (or 'exist') that cannot be proven to exist. Alternatively - since Godel's Incompleteness Theorm is the same thing thing as the Halting Problem - some simulations that can't be proven valid (ie that each step of the simulation halts) are nonetheless valid.
- dvt 6y agoThe problem with these kinds of theories (eternal recurrence, random quantum state fluctuations, simulation): - There are plenty of things that aren't computable that our universe seems to do just fine (entropy being one) - The universe seems to be intelligible, especially w.r.t. its causal chain -- if we only happen to be conscious in these very specific instants (where we have intelligibility, causality, etc.), the question is why? At the end of the day, you end up with some kind of Maxwell's demon type of situation where there's all this trickery that needs to happen to support a theory where we're in a simulation or Boltzmann brains.
- mdoms 6y agoGreg Egan is truly one of the most creative minds on the planet. He has a book called Dichronaughts that's set in a universe with 2 space and 2 time-like dimensions. It's very hard to get your head around but the result is a universe with a hyperbolic geometry where movement on one axis implies changing your shape entirely.
- guscost 6y agoAll formal systems are incomplete or inconsistent. There is zero evidence that the universe is either.
- drdeca 6y agoThere is a difference between a mathematical object and a formal system. Surely you would not call a differential equation with a given initial condition describing a simple harmonic oscillator along with an initial condition “inconsistent”. Would you call it incomplete? Doing so would seem rather odd seeing as there is exactly one solution (given the initial condition). And the sense of “incomplete” that the incompleteness theorems are about doesn’t apply to this. I don’t just mean that it isn’t true of it. I mean that it is not an applicable idea. It is like asking what the northernmost point of the color blue is. People should be careful when trying to apply Gödel’s incompleteness theorems to philosophical questions, as people often do so without really understanding what they say, and, importantly, what they do not say. Something that may help is to familiarize oneself with Gödel’s _completeness_ theorem.
- guscost 6y ago> Surely you would not call a differential equation with a given initial condition describing a simple harmonic oscillator along with an initial condition “inconsistent”. No, certainly not. > Would you call it incomplete? Yes, absolutely. There is no such thing as a harmonic oscillator that exactly follows an equation like that. Show me one. Either the formal system has nothing to do with the real world, or it is an incomplete approximation of it. All other known physical theories are the same way. Can even a part of the universe be described completely by any (incomplete) formal system? Is it even meaningful to talk about a “part” of the universe in this sense? Well, there’s exactly zero evidence either way. That’s what I’m implying when I say “the universe may not be incomplete.”
- drdeca 6y ago> Either the formal system has nothing to do with the real world, or it is an incomplete approximation of it. Ok, but this is a totally separate meaning of “incomplete” than what the incompleteness theorems are talking about. So, if that is what you meant by “incomplete” in your original comment, you should know that your comment looked like it was appealing to Gödel’s incompleteness theorems, which do not deal with that sense of “completeness”.
- maxs 6y agoGreg Egan is my favorite author. My favorite book of his is Diaspora. If you loved Permutation City you may also love Diaspora. The first chapter of Diaspora is brilliant, if you try reading it, and find that you enjoy it, you will then like the whole book.
- _jal 6y agoThumbs up for Diaspora, that's probably my favorite of his. If anyone wants to sample him first, if you like the short stories on his website, you'll almost certainly like his books. https://www.gregegan.net/BIBLIOGRAPHY/Online.html https://www.gregegan.net/BIBLIOGRAPHY/Online.html
- zeroonetwothree 6y agoHis short stories are far better than his novels. Not saying that the novels are bad but rather that the short stories are unreal good.
- blahdeblah 6y agoThe first chapter is on Egan's site: https://www.gregegan.net/DIASPORA/01/Orphanogenesis.html https://www.gregegan.net/DIASPORA/01/Orphanogenesis.html
- visarga 6y ago> In fact, even if you imagine a static set of relations that do not evolve in time there still exists encoding schemes that can interpret this set of relations as any arbitrary function, so in some sense the set of mathematical objects that represent “you” and “me” and all possible minds can be said to exist in these timeless relations. The argument fails because "you" and "me" are processes, embodied agents while the interpretations of data are "virtual".
- garmaine 6y ago> If you think experience is simulatable, you buy computational or “patternist” theories of identity, there are some very strange implications that are not commonly brought up. Maybe the sentence isn't worded correctly, but these are two entirely different claims. It's relatively simple and straightforward to argue that one's experience is simulatable, but that identity lies in the instance of the simulation itself, so a copy of a simulation would be a different being. That two machines running the same computational process represent the same entity is a separate, unverifiable claim.
- idlewords 6y agoThere's a philosophical literature on this, which is also known as the "dancing with pixies" argument. See: https://www.consciousentities.com/2009/07/dancing-pixies/ https://www.consciousentities.com/2009/07/dancing-pixies/ And: http://www.doc.gold.ac.uk/~mas02mb/Selected%20Papers/2009%20Cognitive%20Computing.pdf http://www.doc.gold.ac.uk/~mas02mb/Selected%20Papers/2009%20...
- nkingsy 6y agoJust finished Diaspora. It made me feel rather stupid, as the analogies it weaves throughout (as way to dumb it down I suppose) were sort of like reading the cliff notes. Okay 6 dimensions, ok 12 sure. And this one is 5 dimensions but they’re all sort of visible or something. But really it’s infinite dimensions and all that science proofing I skimmed was wrong. Great. I did love the artificial mind part in the beginning. Is this book a deeper dive on that?
- askvictor 6y agoAll of Egan's books make me feel stupid, but in the best possible way :) I always feel I'm getting half the picture but would need a PhD in whatever speciality he's focussing on in this book to get the whole thing, yet thoroughly enjoy every book all the same. Permutation City is something of a different take on the artificial mind to Diaspora. Schild's Ladder deals also has the artificial mind theme, perhaps a bit closer to Diaspora, but with it's own take again.
- yourkin 6y agoGreg Egan is definitely in the list of authors with the most radically hard science fiction ideas, even more extravagant than those I found in Alfred Bester books. Speaking of the Dust Theory, this looks very close to concept as Max Tegmark's Mathematical universe hypothesis: https://en.wikipedia.org/wiki/Mathematical_universe_hypothesis https://en.wikipedia.org/wiki/Mathematical_universe_hypothes... Tegmark's book goes over it in a very readable way: https://www.amazon.de/Our-Mathematical-Universe-Ultimate-Reality/dp/0241954630 https://www.amazon.de/Our-Mathematical-Universe-Ultimate-Rea...
- scarmig 6y agoI've not read the book, but I'm trying to digest this. For someone who has a good grasp of Dust Theory, if you answer from its perspective... 1) Does believing that consciousness is simulateable commit you to thinking of consciousness as a purely mathematical object, apart from any physical process it might model? 2) If the universe were just an infinite space filled with dust in a wild zoo of different configurations, does my consciousness exist in it so long you can find a dust configuration that admits a mathematical representation that's isomorphic to the one representing my "real" consciousness? 3) How does complexity fit into this? If the entirety of the universe were a single static point particle, would consciousness still fall out of it? It seems as if it could, if you had a sufficiently complicated encoding scheme.
- namanyayg 6y ago1. Yes, what physical processes? It's just signals. 2. I can postulate that to be true, but unless I have hard proof I cannot say it to be true. If that isomorphic consciousness finds _itself_ to have a subjective experience... Then it knows that dust theory exist, no one else does. 3. I do not understand this question
- hgibbs 6y agoWell yes, you could construe any physical object as having conciousness by having a sufficiently detailed/complex schema that assigns 'meanings' to each of its states. But we all agree a rock is not conscious, so this definition doesn't pass the common sense test. One mistake is then claiming that this usage of the word conciousness can be substituted for the commonplace usage in all situations. E.g. why don't we feel the same ethical obligation to a potentially conscious rock that we do to animals, humans and, arguably, seemingly intelligent entities? For a nice exposition of this one can read chapter 2 of Gary Drescher's book 'good and real'.
- mcguire 6y ago"That is, for any random set of relations with enough complexity to represent a human mind, Egan claims, there exists an exotic encoding scheme that can interpret this set of relations as representing any arbitrary function, including the function that you would call “I”." "There exists an X" is significantly different as a statement from "This X" (or "All X", for that matter). Since I assume that solipsism is a fallicy, I don't find this philosophical position all that useful.
- sfink 6y agotl;dr - I am possible, therefore I am.
- saeranv 6y agoDust theory is cool, but I really, really wish someone could simplify and explain the world of Egan's Dichronauts to me.