Yes. The question of "Are we in a sim?" depends on whether we're in a finite computational space type sim or whether we're in a non-finite computational space (i.e. running on a quantum computer).

In a finite sim where we want it to be as realistic as possible, having a high speed of light would mean we'd have to simulate other civilizations too, thus reducing the achievable complexity of the sim on average.

In a finite sim with a low speed of light we only need to simulate locality with any kind of high degree of fidelity.

In an infinite sim, there could conceivably be no detectable difference between base reality and the sim.

Speculating on whether we're in a finite sim, I'd expect to see lots of attempts to compress unneccesarily detailed information and I'd also expect to see level of detail reduced when we're not looking at it. I'd also expect to see non locality happening faster than the speed of light but not necessarily explained by the physics of the sim.

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I agree with whoever said that the simulations wouldn't have to be simulations of historical events (you could argue that simulating a random possible universe would be unlikely to result in this particular universe, but I would shoot that argument down (since you can say that in any universe, provided that the universe exists))

Also, what I took away from the original paper about simulations was not a belief either that we are or aren't simulated. The point, as I see it, is that IF anyone simulates a universe (especially more than one) in the future, it means that we are probably in a simulation.

Also, I have homework to do. The internet is ruining me.

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MichaelG: mammals are rare compared to the average insect or something; primates are pretty rare among the mammals; *social* primates aren't even a majority, I suspect (consider the entire prosimian grouping).

As it is, they have a small niche in a few areas and tend to be going extinct or be under pressure. If they were as common and successful as your average insect species, then that'd be a serious problem.

How do they survive? They probably fit in a niche where a group is powerful enough to kill any hyena or lion that attacks it but small enough to survive mostly off fruits and vegetables in denser forest stands; and the group requires sociality. (I'm not a biologist, I'm just guessing here and going off memories of how chimps can easily kill men and baboons hyenas.)

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What a joke. A probability for something that is not repeatable.

Here's a link to help you get with the program.

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You should have bet on it.

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"We will know for sure that we live in a simulation when we start creating our simulated universes complete with sentient entities who don’t know they are in a simulation." We've already done that, if you adopt a reasonably low definition of sentient.

To play devil's advocate, though, I'd expect more simulations within simulations N deep, if we were in a simulation that was more than 1 level removed from actual reality ourselves.

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What a joke. A probability for something that is not repeatable. Where is my high school stats book?

Suppose your argument made sense. Anyone who believes something because it is likely or even nigh certain is quite clearly a fool. Surely you see this?

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Each modeler of each virtual universe with human simulated brains would do it almost perfectly taking into account the technology according to his psicological desires.So if for a moment we forget about the pure simulation model, and we think on the benefits or intentions the results of these virtual worlds would be different to what we have;this takes away the probability that we are in a virtual world with some clear almost perfect motive and therefore the chances that we are real if we discard the intentions of the modelers are almost 99% real.

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Alan, you said:"To guess the probability that we are in a simulation we need to know about the multiverse: what is the ratio of ur-realities at medium grain to ur-realities at fine grain. "

This is exactly the core of the original simulation argument. The key is it doesn't matter the exact number of different types of universes (or multiverses) in the ensemble, only the ratios matter.

The entire point of the simulation argument is to show:1. that every universe somewhat like ours eventually spawns N child sub-universes (of somewhat lower fidelity)2. that N is very large

thats all you need to show. The simulation argument is only false if N is much less than 1.

We will know for sure that we live in a simulation when we start creating our simulated universes complete with sentient entities who don't know they are in a simulation. It looks highly likely that we will be doing that this century (if we don't die out first).

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The simulation argument gets the level-crossings wrong. There may be a stack of simulated realities with ur-reality at the top. Is our medium grain reality actually at the top? The simulation argument proposes that mankind will run many simulations in the future and tries counting the beings in coarse grained realities one level below ours. They may wish to guess whether they are in a simulation or not. They need to know whether their coarse grained reality could exist independently as an ur-reality, a question which we are poorly placed to answer.

For our part we need to know about the beings in the level above ours. They live in a fine grained reality and are simulating us in our medium grained reality, perhaps giving rise to very many simulated beings at our medium grain level.

To guess the probability that we are in a simulation we need to know about the multiverse: what is the ratio of ur-realities at medium grain to ur-realities at fine grain. This is a key number, if ur-realities at fine grain are more common the simulation argument is stronger in proportion. But we have nothing to go on. Finer grained ur-realities might not exist at all and we are definitely not in a simulation. Medium grained ur-realities might not exist at all and we definitely are in a simulation. Lacking this key number we know nothing and the simulation argument is idle speculation

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Yes rationality denies itself because we must conclude that we most likely live in the simulation with miracles and after-life. :)

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Finally! A logical argument that supports believing in life after death, without requiring any religious faith! Now, if only I could develop a strong faith in your argument, but... well, once a skeptic, always a skeptic, I suppose. Of course, that might simply be the nature of my pre-assigned sim personality.

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Believing you are in a sim is not distinguishable from believing in an omnipotent god (of any type).

I love it! I'm going to use this as a quote at then end of my emails, at least for a while. (Probably not all the way until the sim ends. Maybe just to the next save.)

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Maybe "Game" or "PUA" only works on the simpler women, the ones that are not fully simulated. To tie another common theme from Overcoming Bias into this post.

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I don't believe there are any known inconsistencies between General Relativity, Quantum Mechanics, and Classical mechanics. That is to say, I don't believe there are some situations where QM gives the right answer and GR gives the wrong one, or vice versa.

If there are that you know of, do tell!

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Indeed! I actually pulled up the wiki page on Descartes' meditations and was looking through them as I read some of these entries and thought the same thing.

We also have mjgeddes above denying an external reality. IIRC, that was Bishop Berkeley's position (esse est percipi). In the same course I learned Descartes and Berkeley, we ended with Kant, who seemed to solomonaically split the baby: there is an external reality (noumena) but we can't perceive it, what we perceive is something else (phenomena). I remember thinking if I could understand Kant that I'd have it knocked, but that seminar was the end of that, I went on to study physics.

As part of my philosophical education I studied Popper who I interpret as saying (among many other things) "a difference that makes no difference is no difference." That is, if you think you have a theory that is different from another theory, you must be able to design an experiment that has a different outcome between the two theories. If you can't, you are just rearranging the deck chairs on the Titanic.

So what are the properties of a Sim such that we could not tell we are in a sim? Such a sim, if it existed, IS reality.

Thought experiment: why create expensive new fast computers? Lets just write a simulation of one, and then we can get results really fast by running them on the simulated computer.


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