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CATEGORY: Blog
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TOPIC: Out of Plato's Cave?
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It's becoming something of a trope in contemporary science fiction: the character who believes himself to be in the real world finds out, through a series of enlightenment-style experiences, that what he inhabits is not "ground level" reality but a virtual world of one sort or another. After the runaway success of The Matrix (despite its horrifically bad sequels) virtual realities have made their way from hard sci-fi and introductory philosophy courses into the standard guns-and-leather plots of the silver screen. This suspicion of reality goes back at least as far as Plato, though as a basic idea it is straightforward enough. Whether the technology of any given movie world is plausible or not, as a narrative, we get it: things ain't what they seem.
 | | image: Pathfinder Linden |
A question, though, is raised by all this consciousness-raising: what constitutes ground level reality? Or, in a more positivist vein: what could, even in principle, determine whether any given level were ground?
An interesting recognition of the complexities appears in the 1999 movie The 13th Floor. The movie is a throw-away; I don't mean to recommend it as fine cinema. But the script contains the seed of a relevant epistemological knot. (BEWARE: SPOILERS FOLLOW)
In it, the creators of a virtual Los Angeles, indistinguishable to its cyber-based observers from the real world, find through a long series of adventures that they, themselves, are likewise living in a virtual city. Their lives, which they took to be at level A, were in fact always at A', while the virtual city they built and believed to be at A' was in fact at A''. When the hero emerges -- that enlightenment experience again -- into the actual A-level world, he finds it to be Los Angeles in the future.
 | | image: cogdogblog |
Nice surprise. However, the script touches more or less accidentally on a profound problem. To stay within this scenario, how do observers in A know that they are at ground--that their level is, indeed, A? After all, observers in A' mistook themselves for A, as did observers in A''.
On cursory inspection one is tempted to conclude that there is no way to know, at any level, whether you are at A. All levels must make this pragmatic assumption, but any level could be wrong -- indeed, all could be wrong, if there is an infinite number of foundations. But is this so?
(Note also that this situation of ontological undecidability did not exist until the invention of the virtual city, the first Los Angeles A'. Until any version of A' is fabricated, the currently experienced reality has to be A; there are no other options. However, how can a stable A turn into an uncertain A merely by being the location of some new technology?)
Question, then: is it possible in principle to devise a test -- scientific, quantifiable -- to determine whether the given reality in which the test is run is foundational?
| | this post has been edited by the author since its original submission |
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On the subject of virtual worlds, it turns out that some are now using them to help study the real one (‘RW,’ as the Real World is somewhat disparagingly known among the VR-savvy).
NOAA has this to say about their new Second Life Island:
“NOAA's virtual world takes advantage of a platform known as ‘Second Life’. This platform is a 3-D online world with a rapidly growing population from 100 countries around the globe. Residents themselves create and build everything from homes, vehicles, stores, and landscapes to educational areas like the map.”
 | | image: adactio |
And why not? One of the shibboleths of the scientific enterprise is the GUT, a still-to-be-realized Grand Unified Theory that explains how everything fits together in one neat, mathematical package. No one has provided a definitive GUT yet, but many believe it is “out there” – that is, whether humanity ever figures out how all the numbers crunch, they ultimately do crunch that way.
Underneath this assumption, I believe, lies a deeper one: that the crunching is such that, in some not-understood way, it moves from mathematics to ontology. The ultimate GUT, that is, will be self-subsistent, containing its own explanation (in a multiverse, of course, that ultimate GUT may be many levels of explanation away).
Take away that admittedly untestable meta-assumption and no one much notices, outside of a handful of philosophers of science. Take the lesser assumption away, however – that nature is in some sense a mathematical phenomenon, or at least that there is a one-to-one correspondence between what numbers are and what phenomena do -- and the scientific approach itself wavers. This is largely because the assumption has borne such excellent fruit over the past few centuries, despite the persistent philosophical puzzle of why numbers should “link” to events at all.
Whatever the reason, it seems beyond question that, as Galileo famously put it, the book of nature is written in the language of mathematics. Numbers are either the way we’re going to understand how all of nature works, or they are, in some sense, nature itself. (The same cannot be said of words, for example, as the insufficiency of Hegel’s philosophy shows.)
 | | image: Lady-bug |
The connection to Second Life? If nature is numerical to her core, then a sufficiently detailed simulation of, say, a hurricane should in principle serve not merely as a representation but as an analytic tool; it should be possible using computation to come as close to a natural phenomenon as it is possible to come – sans that mysterious link that equals actual existence. There may well come a time when modeling of nature in virtual space is the preferred method—indeed, perhaps the best method—for understanding phenomena in the poor old RW.
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Anthony – Yes . . . like those moments in Hollywood where the main character realizes he is in a dream state because he is unable to read printed material (supposedly something we can’t do in dreams), or throws himself off a cliff to prove he’s not really there . . .
My personal favorite is the old Twilight Zone episode in which a man, convinced that he is hallucinating the existence of an entire turboprop airplane, fires up the rotors and then walks purposefully toward the spinning blade, saying “This is not real . . . this is not real . . .”
But if the digital computer on which we are running the experiment is also simulation, then our conclusions about what is impossible to simulate are invalid, aren’t they? They will follow the rules of the simulation, but we still wouldn’t know whether those rules are Foundational.
I can imagine a program that is non-replicable, in the sense that it can’t be reproduced in simulation. But I can also imagine a simulation program with that property; if Foundational reality is A, the program could be run at A’ but be unreproducible at A’’, A’’’, and so on. Even if we had such a program we still wouldn’t know whether we were at A.
What about this: is there a mathematical test that could demonstrate that we aren’t at A? Can we assume that math must be true outside any simulation? Say, if we find that a certain necessary axiom is contradicted by experiment, might that prove not that our math is wrong . . . but that our world is false?
(I dunno, like . . . if space at large enough scales seems to be non-Euclidean . . .? :)
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As has been emphasized by Bruno Marchal, who posts here occasionally, in the context of multiverse theories this question is actually meaningless. There is no "fact of the matter" about whether we are in a simulation or in a base-level reality. We are in both; in fact we are in simulations nested N deep for every N. From the first-person perspective our seemingly singular consciousness is implemented identically multiple times throughout the multiverse.
I would emphasize the notion of "measure" as giving perspective to this problem. The idea is that different instantiations of conscious systems in the multiverse each contribute a certain amount to the total measure of the conscious experience. The variability of measure of different experiences is how we understand subjective probabilities.
In this framework, while we can't ask whether we are "really" in a simulation, we can ask how much measure we gain from various simulation scenarios vs from more traditional base realities. This would then correspond to the subjective probability that we are in a simulation.
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Actually, since our brains are simulating (or calculating) us, there is no question about us being in a simulation. I think it is wrong to identify ourselves with our brain. Instead we should identify ourselves with the computations the brain is performing. This seems to me to be more compatible with "Strong AI".
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One could only make a judgement if all possible levels are experienced?..thus starving the brain of oxygen till death for instance, would invoke a unreal experience, without any knowledge gain. One can, and should believe that the conscious brain, functions with the knowledge of a specific "level" of reality. All virtual or unreal events get logged into the fantasy, or "virtual" bracket?
Processing information in any arena, one can make decisive conclusions, a calculator, calculates?..but a calculator with "batteries not included" cannot process information, it cannot function, even though it still "exists"?
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In any virtual world there would be things pop into existence as if by magic, created by beings from a more foundaitonal level. To those inside the virtual world this would appear to be a creative intelligence, or God if you prefer. So the proof that you're inside a virtual world is the proof that a creative intelligence is at work in it. In other words, if you can proof that the laws of thermodynamics are violated, then that would prove that you must be inside a virual world.
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I like this line of thought—that confirmable violations in physical law would demonstrate that we were not at A, but some synthetic A’. Any “break” in the rules could then be taken as evidence of a flaw in the system that reveals the existence of a system.
 | | image:vmperella |
At some point, it must be possible to run down any simulation, or exhaust its processing capacity, producing a “glitch.” Perhaps some very high-energy collision experiment could tax the processor, or a vastly detailed deep-sky survey.
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A similar argument has been raised, actually, as to the energy requirements of synthesizing a significant volume of universe. At some point, the ersatz real estate will cost more to produce than the reality behind it will allow. Rather than giving in to epistemological nihilism, then, the question may be asked of how hard it would be in principle to synthesize a virtual environment with the degree of complexity we observe. Has the galaxy, for example, been in existence long enough to give rise to a civilization likely to be able to access as much power as would be required to build a virtual environment that matches what we (think we) see? The question, some argue, is partly one of volume: the system wouldn’t have to model every event—or indeed, any events that aren’t being observed—but one could argue that it should have trouble with observations happening a significant distance from Earth. There’s a charming essay in the book “Where Is Everybody?” on the question of whether Voyager 1 and 2 are approaching this kind of “synthetic universe horizon.”
| | image:vmperella |
I highly recommend that book, by the way, as a primer on The Fermi Paradox. The full title is “If the Universe Is Teeming with Aliens... Where Is Everybody? Fifty Solutions to Fermi's Paradox and the Problem of Extraterrestrial Life,” and author is Stephen Webb. One solution that has been proposed to the Paradox is the “Galactic Zoo” scenario, whereby the reason we don’t see anybody out there is we aren’t really out there; we’re being kept, for some unknown reason, in a virtual environment where we are the only sentiment species in the galaxy. (From that perspective the Fermi Paradox itself might be argued to be evidence that we are in not at A.)
| | image:vmperella |
The problem, of course, is that for any of this to be plausible we would have to assume that Foundational Reality has no glitches, and we can’t know this. (Can we?) I don’t mean miracles; I mean discontinuities in physical law, such that at very small scales or very high energies the rules don’t always apply. Indeed, we already live with this all the time. Quantum mechanics is quite inured to the idea that an electron can be in two places at once, or that virtual particle pairs briefly violate the conservation of mass/energy. Negative energy potentials and universe popping out of nothing hardly raise an eyebrow these days as credible physics. So what kind of “glitch” could we recognize as such?
| | image:vmperella |
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So, perhaps quantum mechanics is a manifestation of the fact that we live in a simulation? I think we have to consider an ensemble of all possible simulations. Given all the information we have in our brain, there are an infinite number of simulations each implemented slightly differently that could have generated us. The maximum available information is thus not enough to be able to predict the outcome of experiments...
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I think the level of questioning is very important, example:What is the ultimate reality? to whom the question is posed is vital!
Well if this is asked to an "ultimate computer"?..then I personally would expect the virtual computer to argue that my existence is just "functional", within a percived universe reality.
If this is how things are, then I would ask this to the computer:Show me the Universe without me inside it, infact I would insist on proof that I could be outside the Universe looking in !
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