I've already answered this
But the answer you go on to repeat is one I already explained wasn't relevant, in the sentence after the one you quoted.
most of the additional cost boils down to a constant factor once you amortize at large scale.
I'm not sure what you're arguing. I agree that the additional cost is basically a (large) constant factor; that is, if it costs X to simulate a freshly made new mind, maybe it costs 1000X to recover the details of a long-dead one and simulate that instead. (The factor might well be much more than 1000.) I don't understand how this is any sort of counterargument to my suggestion that it's a reason to simulate new minds rather than old.
the amount of information remaining about my grandfather who died in the 1950's is pretty small.
You say that like it's a good thing, but what it actually means is that almost certainly we can't bring your grandfather back to life, no matter what technology we have. Perhaps we could make someone who somewhat resembles your grandfather, but that's all. Why would you prefer that over making new minds so much as to justify the large extra expense of getting the best approximation we can?
you always need one copy to remain in the historical sim for consistency
I'm not sure what that means. I'd expect that you use the historical simulation in the objective function for the (enormous) optimization problem of determining all the parameters that govern their brain, and then you throw it away and plug the resulting mind into your not-historical simulation. It will always have been the case that at one point you did the historical simulation, but the other simulation won't start going wrong just because you shut down the historical one.
Anyway: as I said before, if you expect lots of historical simulation just to figure out what to put into the non-historical simulation, then that's another reason to think that ancestor simulation is very expensive (because you have to do all that historical simulation). On the other hand, if you expect that a small amount of historical simulation will suffice then (1) I don't believe you (if you're estimating the parameters this way, you'll need to do a lot of it; any optimization procedure needs to evaluate the objective function many times) and (2) in that case surely there are anthropic reasons to find this scenario unlikely, because then we should be very surprised to find ourselves in the historical sim rather than the non-historical one that's the real purpose.
When I say this tech isn't that far away, it's because AGI isn't that far away, and this follows shortly thereafter.
Perhaps I am just misinterpreting your tone (easily done with written communication) but it seems to me that you're outrageously overconfident about what's going to happen on what timescales. We don't know whether, or when, AGI will be achieved. We don't know whether when it is it will rapidly turn into way-superhuman intelligence, or whether that will happen much slower (e.g., depending on hardware technology development which may not be sped up much by slightly-superhuman AGI), or even whether actually the technological wins that would lead to very-superhuman AGI simply aren't possible for some kind of fundamental physical reason we haven't grasped. We don't know whether, if we do make a strongly superhuman AGI, it will enable us to achieve anything resembling our current goals, or whether it will take us apart to use our atoms for something we don't value at all.
You are assuming naive encoding without compression
No, I am assuming that smarter encoding doesn't buy you more than the outrageous amount by which I shrank the complexity by assuming only one parameter per synapse.
that gives a lower bound of 10^10 for a 100 year old
Tried optimizing a function of 10^10 parameters recently? It tends to take a while and converge to the wrong local optimum.
naysayers will always be able to claim "these aren't really the same people". But their opinions are worthless. The only opinions that matter are those who actually knew the relevant people
What makes you think those are different people's opinions? If you present me with a simulated person who purports to be my dead grandfather, and I learn that he's reconstructed from as little information as (I think) we both expect actually to be available, then I will not regard it as the same person as my grandfather. Perhaps I will have no way of telling the difference (since my own reactions on interacting with this simulated person can be available to the optimization process -- if I don't mind hundreds of years of simulated-me being used for that purpose) but there's a big difference between "I can't prove it's not him" and "I have good reason to think it's him".
I don't really have a great deal of time to explain this so I"ll be brief. Basically this is something I've thought a great deal about and I have a rather detailed technical vision on how to achieve (At least to the extant that anyone can today. I'm an expert in the relevant fields - computer simulation/graphics and machine learning, and this is my long term life goal.). Fully explaining a rough roadmap would require a small book or long paper, so just keep that in mind.
...most of the additional cost boils down to a constant factor once you amortiz
This is a bit rough, but I think that it is an interesting and potentially compelling idea. To keep this short, and accordingly increase the number of eyes over it, I have only sketched the bare bones of the idea.
1) Empirically, people have varying intuitions and beliefs about causality, particularly in Newcomb-like problems (http://wiki.lesswrong.com/wiki/Newcomb's_problem, http://philpapers.org/surveys/results.pl, and https://en.wikipedia.org/wiki/Irresistible_grace).
2) Also, as an empirical matter, some people believe in taking actions after the fact, such as one-boxing, or Calvinist “irresistible grace”, to try to ensure or conform with a seemingly already determined outcome. This might be out of a sense of retrocausality, performance, moral honesty, etc. What matters is that we know that they will act it out, despite it violating common sense causality. There has been some great work on decision theory on LW about trying to thread this needle well.
3) The second disjunct of the simulation argument (http://wiki.lesswrong.com/wiki/Simulation_argument) shows that the decision making of humanity is evidentially relevant in what our subjective credence should be that we are in a simulation. That is to say, if we are actively headed toward making simulations, we should increase our credence of being in a simulation, if we are actively headed away from making simulations, through either existential risk or law/policy against it, we should decrease our credence.
4) Many, if not most, people would like for there to be a pleasant afterlife after death, especially if we could be reunited with loved ones.
5) There is no reason to believe that simulations which are otherwise nearly identical copies of our world, could not contain, after the simulated bodily death of the participants, an extremely long-duration, though finite, "heaven"-like afterlife shared by simulation participants.
6) Our heading towards creating such simulations, especially if they were capable of nesting simulations, should increase credence that we exist in such a simulation and should perhaps expect a heaven-like afterlife of long, though finite, duration.
7) Those who believe in alternative causality, or retrocausality, in Newcomb-like situations should be especially excited about the opportunity to push the world towards surviving, allowing these types of simulations, and creating them, as it would potentially suggest, analogously, that if they work towards creating simulations with heaven-like afterlives, that they might in some sense be “causing” such a heaven to exist for themselves, and even for friends and family who have already died. Such an idea of life-after-death, and especially for being reunited with loved ones, can be extremely compelling.
8) I believe that people matching the above description, that is, holding both an intuition in alternative causality, and finding such a heaven-like-afterlife compelling, exist. Further, the existence of such people, and their associated motivation to try to create such simulations, should increase the credence even of two-boxing types, that we already live in such a world with a heaven-like afterlife. This is because knowledge of a motivated minority desiring simulations should increase credence in the likely success of simulations. This is essentially showing that “this probably happened before, one level up” from the two-box perspective.
9) As an empirical matter, I also think that there are people who would find the idea of creating simulations with heaven-like afterlives compelling, even if they are not one-boxers, from a simply altruistic perspective, both since it is a nice thing to do for the future sim people, who can, for example, probabilistically have a much better existence than biological children on earth can, and as it is a nice thing to do to increase the credence (and emotional comfort) of both one-boxers and two-boxers in our world thinking that there might be a life after death.
10) This creates the opportunity for a secular movement in which people work towards creating these simulations, and use this work and potential success in order to derive comfort and meaning from their life. For example, making donations to a simulation-creating or promoting, or existential threat avoiding, think-tank after a loved one’s death, partially symbolically, partially hopefully.
11) There is at least some room for Pascalian considerations even for two-boxers who allow for some humility in their beliefs. Nozick believed one-boxers will become two boxers if Box A is raised to 900,000, and two-boxers will become one-boxers if Box A is lowered to $1. Similarly, trying to work towards these simulations, even if you do not find it altruistically compelling, and even if you think that the odds of alternative or retrocausality is infinitesimally small, might make sense in that the reward could be extremely large, including potentially trillions of lifetimes worth of time spent in an afterlife “heaven” with friends and family.
Finally, this idea might be one worth filling in (I have been, in my private notes for over a year, but am a bit shy to debut that all just yet, even working up the courage to post this was difficult) if only because it is interesting, and could be used as a hook to get more people interested in existential risk, including the AI control problem. This is because existential catastrophe is probably the best enemy of credence in the future of such simulations, and accordingly in our reasonable credence in thinking that we have such a heaven awaiting us after death now. A short hook headline like “avoiding existential risk is key to afterlife” can get a conversation going. I can imagine Salon, etc. taking another swipe at it, and in doing so, creating publicity which would help in finding more similar minded folks to get involved in the work of MIRI, FHI, CEA etc. There are also some really interesting ideas about acausal trade, and game theory between higher and lower worlds, as a form of “compulsion” in which they punish worlds for not creating heaven containing simulations (therefore effecting their credence as observers of the simulation), in order to reach an equilibrium in which simulations with heaven-like afterlives are universal, or nearly universal. More on that later if this is received well.
Also, if anyone would like to join with me in researching, bull sessioning, or writing about this stuff, please feel free to IM me. Also, if anyone has a really good, non-obvious pin with which to pop my balloon, preferably in a gentle way, it would be really appreciated. I am spending a lot of energy and time on this if it is fundamentally flawed in some way.
Thank you.
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November 11 Updates and Edits for Clarification
1) There seems to be confusion about what I mean by self-location and credence. A good way to think of this is the Sleeping Beauty Problem (https://wiki.lesswrong.com/wiki/Sleeping_Beauty_problem)
If I imagine myself as Sleeping Beauty (and who doesn’t?), and I am asked on Sunday what my credence is that the coin will be tails, I will say 1/2. If I am awakened during the experiment without being told which day it is and am asked what my credence is that the coin was tails, I will say 2/3. If I am then told it is Monday, I will update my credence to ½. If I am told it is Tuesday I update my credence to 1. If someone asks me two days after the experiment about my credence of it being tails, if I somehow do not know the days of the week still, I will say ½. Credence changes with where you are, and with what information you have. As we might be in a simulation, we are somewhere in the “experiment days” and information can help orient our credence. As humanity potentially has some say in whether or not we are in a simulation, information about how humans make decisions about these types of things can and should effect our credence.
Imagine Sleeping Beauty is a lesswrong reader. If Sleeping Beauty is unfamiliar with the simulation argument, and someone asks her about her credence of being in a simulation, she probably answers something like 0.0000000001% (all numbers for illustrative purposes only). If someone shows her the simulation argument, she increases to 1%. If she stumbles across this blog entry, she increases her credence to 2%, and adds some credence to the additional hypothesis that it may be a simulation with an afterlife. If she sees that a ton of people get really interested in this idea, and start raising funds to build simulations in the future and to lobby governments both for great AI safeguards and for regulation of future simulations, she raises her credence to 4%. If she lives through the AI superintelligence explosion and simulations are being built, but not yet turned on, her credence increases to 20%. If humanity turns them on, it increases to 50%. If there are trillions of them, she increases her credence to 60%. If 99% of simulations survive their own run-ins with artificial superintelligence and produce their own simulations, she increases her credence to 95%.
2) This set of simulations does not need to recreate the current world or any specific people in it. That is a different idea that is not necessary to this argument. As written the argument is premised on the idea of creating fully unique people. The point would be to increase our credence that we are functionally identical in type to the unique individuals in the simulation. This is done by creating ignorance or uncertainty in simulations, so that the majority of people similarly situated, in a world which may or may not be in a simulation, are in fact in a simulation. This should, in our ignorance, increase our credence that we are in a simulation. The point is about how we self-locate, as discussed in the original article by Bostrom. It is a short 12-page read, and if you have not read it yet, I would encourage it: http://simulation-argument.com/simulation.html. The point about past loved ones I was making was to bring up the possibility that the simulations could be designed to transfer people to a separate after-life simulation where they could be reunited after dying in the first part of the simulation. This was not about trying to create something for us to upload ourselves into, along with attempted replicas of dead loved ones. This staying-in-one simulation through two phases, a short life, and relatively long afterlife, also has the advantage of circumventing the teletransportation paradox as “all of the person" can be moved into the afterlife part of the simulation.