RE: [agi] the universe is computable [Was: Occam's Razor and its abuse]
From: Matt Mahoney [mailto:[EMAIL PROTECTED] --- On Thu, 10/30/08, John G. Rose [EMAIL PROTECTED] wrote: You can't compute the universe within this universe because the computation would have to include itself. Exactly. That is why our model of physics must be probabilistic (quantum mechanics). I'd venture to say that ANY computation is an estimation unless the computation is itself. To compute the universe you could estimate it but that computation is an estimation unless the computation is the universe. Thus the universe itself IS an exact computation just as a chair for example is an exact computation existing uniquely as itself. Any other computation of that chair is an estimation. IOW a computation is itself unless it is an approximation of something else, it's somewhere between being partially exact or a partially exact anti-representation. A computation mimicking another same computation would be partially exact taking time and space into account. Though there may be some subatomic symmetric simultaneity that violates what I'm saying above not sure. Also it's early in the morning and I'm actually just blabbing here so this all may be relatively inexact :) John --- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?member_id=8660244id_secret=117534816-b15a34 Powered by Listbox: http://www.listbox.com
RE: [agi] the universe is computable [Was: Occam's Razor and its abuse]
I would like to state a middle ground between the viewpoints cited in the email below: It seems to me that if one had a man-made computer capable of computing all the astronically-large and planks-length-fine state information and computations that take place in all of reality at the level described by physics --- if we assummed that all the laws of physicse used were totally correct and complete --- that such a computer would be capable of simulating (given the limitations of the uncertainty principal) all of reality, including its higher levels of organization, such as, for example, the behavior of the human mind, popular culture, and stock markets. It is my believe that reality itself is such a computer, but is it not man-made, and our ability to control and understand its computations is limited. Since the above hypothisized man-made computer would be computing it all, it would have no need for higher level generalizations, such as our understandings of biology, astronomy, geology, psychology, brain science, economics, culture, politics, etc. But if you are going to try to simulate such higher levels of reality's organization without such an all-knowing, all-understanding hypothetical computer, you are much more likely to have success if your computer takes advantages of models derived from experience in terms of generalities (i.e., simplifications, including some derived by Occam's Razor) described in, and derived from, higher levels of organization that are more relevant to the particular higher levels of reality that you want to simulate. Since it is my belief that it is impossible to make out of reality a computer that computes the complexity of reality even close to as fast or as thoroughly as reality itself, I think it is vital to the survival of humanity that we continue to use models which involve simplifications derived from levels of organization higher than those described by what is traditionally called physics. Ed Porter -Original Message- From: Pei Wang [mailto:[EMAIL PROTECTED] Sent: Thursday, October 30, 2008 5:09 PM To: agi@v2.listbox.com Subject: Re: [agi] the universe is computable [Was: Occam's Razor and its abuse] On Thu, Oct 30, 2008 at 5:00 PM, Ben Goertzel [EMAIL PROTECTED] wrote: So there are physicists who think in principle the stock market can be accurately predicated from quantum theory alone? I'd like to get a reference on that. ;-) Pei, I think a majority -- or at least a substantial plurality -- of physicists think that. Really. ben Too bad --- they all should take a course in philosophy of science. Even if that is the case, I don't accept it as a reason to tolerant this opinion in AGI research. Pei --- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?; Powered by Listbox: http://www.listbox.com --- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?member_id=8660244id_secret=117534816-b15a34 Powered by Listbox: http://www.listbox.com
Re: [agi] the universe is computable [Was: Occam's Razor and its abuse]
--- On Thu, 10/30/08, Pei Wang [EMAIL PROTECTED] wrote: [C]. Because of B, the universe can be simulated in Turing Machine. This is where I start to feel uncomfortable. The theory cannot be tested directly because there is no such thing as a real Turing machine. But we can show that the observable universe has finite information content according to the known laws of physics and cosmology, which assumes finite age, size, and mass. In particular, the Bekenstein bound of the Hubble radius gives an exact number (2.91 x 10^122 bits). http://en.wikipedia.org/wiki/Bekenstein_bound http://en.wikipedia.org/wiki/Age_of_the_universe This does not mean you could model the universe. It would be impossible to build a memory this large. Any physically realizable computer would have to be built inside our observable universe. But that is not a requirement for Occam's Razor to hold. I realize we don't have a complete theory of physics. In particular, quantum mechanics has not been unified with general relativity. I also realize that even if we did have a complete theory, we couldn't prove it. -- Matt Mahoney, [EMAIL PROTECTED] --- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?member_id=8660244id_secret=117534816-b15a34 Powered by Listbox: http://www.listbox.com
Re: [agi] the universe is computable [Was: Occam's Razor and its abuse]
Matt, I understand your explanation, but you haven't answered my main problem here: why to simulate the universe we only need physics, but not chemistry, biology, psychology, history, philosophy, ...? Why not to say all human knowledge? Pei On Thu, Oct 30, 2008 at 1:51 PM, Matt Mahoney [EMAIL PROTECTED] wrote: --- On Thu, 10/30/08, Pei Wang [EMAIL PROTECTED] wrote: [C]. Because of B, the universe can be simulated in Turing Machine. This is where I start to feel uncomfortable. The theory cannot be tested directly because there is no such thing as a real Turing machine. But we can show that the observable universe has finite information content according to the known laws of physics and cosmology, which assumes finite age, size, and mass. In particular, the Bekenstein bound of the Hubble radius gives an exact number (2.91 x 10^122 bits). http://en.wikipedia.org/wiki/Bekenstein_bound http://en.wikipedia.org/wiki/Age_of_the_universe This does not mean you could model the universe. It would be impossible to build a memory this large. Any physically realizable computer would have to be built inside our observable universe. But that is not a requirement for Occam's Razor to hold. I realize we don't have a complete theory of physics. In particular, quantum mechanics has not been unified with general relativity. I also realize that even if we did have a complete theory, we couldn't prove it. -- Matt Mahoney, [EMAIL PROTECTED] --- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?; Powered by Listbox: http://www.listbox.com --- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?member_id=8660244id_secret=117534816-b15a34 Powered by Listbox: http://www.listbox.com
Re: [agi] the universe is computable [Was: Occam's Razor and its abuse]
--- On Thu, 10/30/08, Pei Wang [EMAIL PROTECTED] wrote: I understand your explanation, but you haven't answered my main problem here: why to simulate the universe we only need physics, but not chemistry, biology, psychology, history, philosophy, ...? Why not to say all human knowledge? An exact description of the quantum state of the universe gives you everything else. There is no requirement that the computation be tractable for Occam's Razor to hold. AIXI only requires that the environment have a probability distribution that is computable by a Turing machine. -- Matt Mahoney, [EMAIL PROTECTED] --- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?member_id=8660244id_secret=117534816-b15a34 Powered by Listbox: http://www.listbox.com
Re: [agi] the universe is computable [Was: Occam's Razor and its abuse]
On Thu, Oct 30, 2008 at 3:07 PM, Matt Mahoney [EMAIL PROTECTED] wrote: An exact description of the quantum state of the universe gives you everything else. Why? Just because it is the smallest object we know? Is this a self-evident commonsense, or a conclusion from physics? As I said before, this is a very strong version of reductionism. It was widely accepted in the time of Newton and Laplace, but I don't think it is still considered as a valid theory in philosophy of science. This position is not only unjustifiable, but also lead the research to wrong directions. It is like to suggest an architect to analyze the structure of a building at atom level, because all building materials are made by atoms, after all. The fact that all building materials are indeed made by atoms only makes the suggestion even more harmful than a suggestion based on false statements. Pei --- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?member_id=8660244id_secret=117534816-b15a34 Powered by Listbox: http://www.listbox.com
Re: [agi] the universe is computable [Was: Occam's Razor and its abuse]
On Thu, Oct 30, 2008 at 4:50 PM, Pei Wang [EMAIL PROTECTED] wrote: On Thu, Oct 30, 2008 at 3:07 PM, Matt Mahoney [EMAIL PROTECTED] wrote: An exact description of the quantum state of the universe gives you everything else. Why? Just because it is the smallest object we know? Is this a self-evident commonsense, or a conclusion from physics? It's an implication of quantum theory. However, it's not yet fully validated experimentally or theoretically. No one has ever, for instance, derived the periodic table of the elements from the laws of physics, without making a lot of hacky assumptions that amount to using known facts of chemistry to tune various constants in the derivations. ben g As I said before, this is a very strong version of reductionism. It was widely accepted in the time of Newton and Laplace, but I don't think it is still considered as a valid theory in philosophy of science. This position is not only unjustifiable, but also lead the research to wrong directions. It is like to suggest an architect to analyze the structure of a building at atom level, because all building materials are made by atoms, after all. The fact that all building materials are indeed made by atoms only makes the suggestion even more harmful than a suggestion based on false statements. Pei --- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?; Powered by Listbox: http://www.listbox.com -- Ben Goertzel, PhD CEO, Novamente LLC and Biomind LLC Director of Research, SIAI [EMAIL PROTECTED] A human being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects. -- Robert Heinlein --- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?member_id=8660244id_secret=117534816-b15a34 Powered by Listbox: http://www.listbox.com
Re: [agi] the universe is computable [Was: Occam's Razor and its abuse]
On Thu, Oct 30, 2008 at 4:59 PM, Pei Wang [EMAIL PROTECTED] wrote: On Thu, Oct 30, 2008 at 4:53 PM, Ben Goertzel [EMAIL PROTECTED] wrote: On Thu, Oct 30, 2008 at 4:50 PM, Pei Wang [EMAIL PROTECTED] wrote: On Thu, Oct 30, 2008 at 3:07 PM, Matt Mahoney [EMAIL PROTECTED] wrote: An exact description of the quantum state of the universe gives you everything else. Why? Just because it is the smallest object we know? Is this a self-evident commonsense, or a conclusion from physics? It's an implication of quantum theory. So there are physicists who think in principle the stock market can be accurately predicated from quantum theory alone? I'd like to get a reference on that. ;-) Pei, I think a majority -- or at least a substantial plurality -- of physicists think that. Really. ben --- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?member_id=8660244id_secret=117534816-b15a34 Powered by Listbox: http://www.listbox.com
Re: [agi] the universe is computable [Was: Occam's Razor and its abuse]
On Thu, Oct 30, 2008 at 5:00 PM, Ben Goertzel [EMAIL PROTECTED] wrote: So there are physicists who think in principle the stock market can be accurately predicated from quantum theory alone? I'd like to get a reference on that. ;-) Pei, I think a majority -- or at least a substantial plurality -- of physicists think that. Really. ben Too bad --- they all should take a course in philosophy of science. Even if that is the case, I don't accept it as a reason to tolerant this opinion in AGI research. Pei --- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?member_id=8660244id_secret=117534816-b15a34 Powered by Listbox: http://www.listbox.com
Re: [agi] the universe is computable [Was: Occam's Razor and its abuse]
--- On Thu, 10/30/08, Pei Wang [EMAIL PROTECTED] wrote: So there are physicists who think in principle the stock market can be accurately predicated from quantum theory alone? I'd like to get a reference on that. ;-) If you had a Turing machine, yes. It also assumes you know which of the possible 2^(2^409) possible states the universe is in. (2^409 ~ 2.9 x 10^122 bits = entropy of the universe). So don't expect any experimental verification. However, AIXI suggests a simpler explanation for our existence. Consider an enumeration of Turing machines, such that the n'th machine is run for n steps until a universe containing intelligent life is found. In this case, our universe could have been computed in 2^818 steps. -- Matt Mahoney, [EMAIL PROTECTED] --- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?member_id=8660244id_secret=117534816-b15a34 Powered by Listbox: http://www.listbox.com
Re: [agi] the universe is computable [Was: Occam's Razor and its abuse]
--- On Thu, 10/30/08, Mike Tintner [EMAIL PROTECTED] wrote: The real flaw in physics-based reductionism is that you cannot explain *evolution*/*creativity*. The explanation is the anthropic principle. If the physics of our universe did not allow for evolution of intelligent life, then we wouldn't be here to ask the question. -- Matt Mahoney, [EMAIL PROTECTED] --- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?member_id=8660244id_secret=117534816-b15a34 Powered by Listbox: http://www.listbox.com
Re: [agi] the universe is computable [Was: Occam's Razor and its abuse]
On Thu, Oct 30, 2008 at 5:18 PM, Matt Mahoney [EMAIL PROTECTED] wrote: --- On Thu, 10/30/08, Pei Wang [EMAIL PROTECTED] wrote: So there are physicists who think in principle the stock market can be accurately predicated from quantum theory alone? I'd like to get a reference on that. ;-) If you had a Turing machine, yes. It also assumes you know which of the possible 2^(2^409) possible states the universe is in. (2^409 ~ 2.9 x 10^122 bits = entropy of the universe). So don't expect any experimental verification. Matt, Even if all of our models of the universe can be put into a Turing Machine, your conclusion still doesn't follow, because you need to further assume the model is perfect, that is, it describes the universe *as it is*. This is another conclusion that conflict with the current understanding of science. Pei --- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?member_id=8660244id_secret=117534816-b15a34 Powered by Listbox: http://www.listbox.com
Re: [agi] the universe is computable [Was: Occam's Razor and its abuse]
This is why I keep banging on about Kauffman's Reinventing the Sacred.It deals precisely with this. And it makes the connection - as AI/AGI-ers completely fail to do between all kinds of creativity - from low-level evolutionary creativity to high-level human and social creativity. (BTW evolution and creativity have themselves evolved and taken on new forms - and will continue to do so). I'm not sure why you're so pumped about Kauffman as regards creativity ... I like his work, but it's not as though he gives any kind of detailed explanation of how specific acts of human creativity come about Your big argument against my approach to AGI seems to be that I haven't give detailed, step-by-step explanations of how human-level-AI-type acts of creativity would come about in a system built according to my designs... My counterargument is that in a system like OpenCogPrime, any substantial creative act is going to arise via the combination of a huge number of small cognitive acts interrelating in complex ways. So there is no reason to expect it to be simple to give a detailed explanation of how a substantial creative act will come about in the system ... I think it might take weeks of effort to chart out the possible dynamics of a single substantial creative act within the OpenCogPrime system. This might well be an interesting exercise to carry out, but I haven't yet done it. Now, what does Kauffman do? Does he explain in detail how some particular, substantial creative act might emerge in a human brain, or an AI system? No. He lays out some general principles and ideas, and then gives examples from much simpler systems, whose resemblance to AGI systems is highly theory-dependent. In short, he -- like me -- thinks that any substantial creative act is going to arise via the combination of a huge number of small cognitive acts interrelating in complex ways ... so that there is no reason to expect it to be simple to give a detailed explanation of how a substantial creative act will come about in a complex system like the human brain ... ben g --- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?member_id=8660244id_secret=117534816-b15a34 Powered by Listbox: http://www.listbox.com
Re: [agi] the universe is computable [Was: Occam's Razor and its abuse]
I note that physicists have frequently, throughout the last few hundred years, expressed confidence in their understanding of the whole universe ... and then been proven wrong by later generations of physicists... Personally I find it highly unlikely that the current physical understanding of the universe as a whole is going to survive the next century ... especially with the Singularity looming and all that. Most likely, superintelligent AGIs will tell us why our current physics ideas are very limited. Fortunately, we don't seem to need to understand the physical universe very completely in order to build AGIs at the human level and beyond. -- Ben G On Thu, Oct 30, 2008 at 5:29 PM, Pei Wang [EMAIL PROTECTED] wrote: On Thu, Oct 30, 2008 at 5:18 PM, Matt Mahoney [EMAIL PROTECTED] wrote: --- On Thu, 10/30/08, Pei Wang [EMAIL PROTECTED] wrote: So there are physicists who think in principle the stock market can be accurately predicated from quantum theory alone? I'd like to get a reference on that. ;-) If you had a Turing machine, yes. It also assumes you know which of the possible 2^(2^409) possible states the universe is in. (2^409 ~ 2.9 x 10^122 bits = entropy of the universe). So don't expect any experimental verification. Matt, Even if all of our models of the universe can be put into a Turing Machine, your conclusion still doesn't follow, because you need to further assume the model is perfect, that is, it describes the universe *as it is*. This is another conclusion that conflict with the current understanding of science. Pei --- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?; Powered by Listbox: http://www.listbox.com -- Ben Goertzel, PhD CEO, Novamente LLC and Biomind LLC Director of Research, SIAI [EMAIL PROTECTED] A human being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects. -- Robert Heinlein --- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?member_id=8660244id_secret=117534816-b15a34 Powered by Listbox: http://www.listbox.com
Re: [agi] the universe is computable [Was: Occam's Razor and its abuse]
While I am actually a fan of Occam's Razor as a guiding principle for AGI, I really don't think AGI should base itself on assumptions like physics is computable In fact, this assumption seems to me an egregious *violation* of Occam's Razor!! Occam's Razor says we should make the minimum hypotheses needed. Hypothesizing a computable universe is almost *surely* nowhere near the minimum hypothesis needed to guide the creation of an AGI -- Ben G On Thu, Oct 30, 2008 at 5:36 PM, Matt Mahoney [EMAIL PROTECTED] wrote: --- On Thu, 10/30/08, Pei Wang [EMAIL PROTECTED] wrote: Even if that is the case, I don't accept it as a reason to tolerant this opinion in AGI research. The point is not that AGI should model things at the level of atoms. The point is that we should apply the principle of Occam's Razor to machine learning and AGI. We already do that in all practical learning algorithms. For example in NARS, a link between two concepts like (if X then Y) has a probability and a confidence that depends on the counts of (X,Y) and (X, not Y). This model is a simplification from a sequence of n events (with algorithmic complexity 2n) to two small integers (with algorithmic complexity 2 log n). The reason this often works in practice is Occam's Razor. That might not be the case if physics were not computable. -- Matt Mahoney, [EMAIL PROTECTED] --- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?; Powered by Listbox: http://www.listbox.com -- Ben Goertzel, PhD CEO, Novamente LLC and Biomind LLC Director of Research, SIAI [EMAIL PROTECTED] A human being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects. -- Robert Heinlein --- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?member_id=8660244id_secret=117534816-b15a34 Powered by Listbox: http://www.listbox.com
Re: [agi] the universe is computable [Was: Occam's Razor and its abuse]
Ben, Kauffman does not provide a new worldview, certainly - he merely identifies the need for one - and he shows how this is necessary at every level from basic physics to economics and our psychology of thinking. He crucially shows that this worldview must incorporate the creative principle which is evident at every level of evolution - and which is of central importance for AGI. I don't think, as I said, that his is a major work, precisely because he doesn't have any new theory about the creative principle. But it's an important valuable work - a stepping stone - because our worldview is about to change (much as our economic-and-poltical world order is about to change!). Thanks for your more detailed points in answer to my criticisms of AGI's lack of creativity. But if I may, I'll reply in a more considered way another time - the criticisms still hold :). Ben/MT: This is why I keep banging on about Kauffman's Reinventing the Sacred.It deals precisely with this. And it makes the connection - as AI/AGI-ers completely fail to do between all kinds of creativity - from low-level evolutionary creativity to high-level human and social creativity. (BTW evolution and creativity have themselves evolved and taken on new forms - and will continue to do so). I'm not sure why you're so pumped about Kauffman as regards creativity ... I like his work, but it's not as though he gives any kind of detailed explanation of how specific acts of human creativity come about Your big argument against my approach to AGI seems to be that I haven't give detailed, step-by-step explanations of how human-level-AI-type acts of creativity would come about in a system built according to my designs... My counterargument is that in a system like OpenCogPrime, any substantial creative act is going to arise via the combination of a huge number of small cognitive acts interrelating in complex ways. So there is no reason to expect it to be simple to give a detailed explanation of how a substantial creative act will come about in the system ... I think it might take weeks of effort to chart out the possible dynamics of a single substantial creative act within the OpenCogPrime system. This might well be an interesting exercise to carry out, but I haven't yet done it. Now, what does Kauffman do? Does he explain in detail how some particular, substantial creative act might emerge in a human brain, or an AI system? No. He lays out some general principles and ideas, and then gives examples from much simpler systems, whose resemblance to AGI systems is highly theory-dependent. In short, he -- like me -- thinks that any substantial creative act is going to arise via the combination of a huge number of small cognitive acts interrelating in complex ways ... so that there is no reason to expect it to be simple to give a detailed explanation of how a substantial creative act will come about in a complex system like the human brain ... ben g -- agi | Archives | Modify Your Subscription --- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?member_id=8660244id_secret=117534816-b15a34 Powered by Listbox: http://www.listbox.com
Re: [agi] the universe is computable [Was: Occam's Razor and its abuse]
If I can assume that Turing machines exist, then I can assume perfect knowledge of the state of the universe. It doesn't change my conclusion that the universe is computable. -- Matt Mahoney, [EMAIL PROTECTED] 1) Turing machines are mathematical abstractions and don't physically exist 2) I thought **I** had a lot of hubris but ... wow! Color me skeptical that you possess perfect knowledge of the state of the universe ;-) ben g --- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?member_id=8660244id_secret=117534816-b15a34 Powered by Listbox: http://www.listbox.com
Re: [agi] the universe is computable [Was: Occam's Razor and its abuse]
Ben, you missed my point. We use Turing machines in all kinds of computer science proofs, even though you can't build one. Turing machines have infinite memory, so it is not unreasonable to assume that if Turing machines did exist, then one could store the 2^409 bits needed to describe the quantum state of the observable universe and then perform computations on that data to predict the future. I described how a Turing machine could obtain that knowledge in about 2^818 steps by enumerating all possible universes until intelligent life is found. As evidence, I suggest that the algorithmic complexity of the free parameters in string theory, general relativity, and the initial state of the Big Bang is on the order of a few hundred bits. -- Matt Mahoney, [EMAIL PROTECTED] --- On Thu, 10/30/08, Ben Goertzel [EMAIL PROTECTED] wrote: From: Ben Goertzel [EMAIL PROTECTED] Subject: Re: [agi] the universe is computable [Was: Occam's Razor and its abuse] To: agi@v2.listbox.com Date: Thursday, October 30, 2008, 6:02 PM If I can assume that Turing machines exist, then I can assume perfect knowledge of the state of the universe. It doesn't change my conclusion that the universe is computable. -- Matt Mahoney, [EMAIL PROTECTED] 1) Turing machines are mathematical abstractions and don't physically exist 2) I thought **I** had a lot of hubris but ... wow! Color me skeptical that you possess perfect knowledge of the state of the universe ;-) ben g agi | Archives | Modify Your Subscription --- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?member_id=8660244id_secret=117534816-b15a34 Powered by Listbox: http://www.listbox.com
RE: [agi] the universe is computable [Was: Occam's Razor and its abuse]
You can't compute the universe within this universe because the computation would have to include itself. Also there's not enough energy to power the computation. But if the universe is not what we think it is, perhaps it is computable since all kinds of assumptions are made about it, structurally and so forth. John --- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?member_id=8660244id_secret=117534816-b15a34 Powered by Listbox: http://www.listbox.com
Re: [agi] the universe is computable [Was: Occam's Razor and its abuse]
On Thu, Oct 30, 2008 at 5:36 PM, Matt Mahoney [EMAIL PROTECTED] wrote: The point is not that AGI should model things at the level of atoms. I didn't blame anyone for doing that. What I said is: to predict the environment as a Turing Machine (symbol by symbol) is just like to construct a building atom by atom. The problem is not merely in complexity, but in the level of description. The point is that we should apply the principle of Occam's Razor to machine learning and AGI. If by Occam's Razor you mean the learning mechanism should prefer simpler result, I don't think anyone has disagreed (though people may not use that term, or may justify it differently), but if by Occam's Razor you mean learning should start by giving simpler hypotheses higher prior probability, I still don't see why. We already do that in all practical learning algorithms. For example in NARS, a link between two concepts like (if X then Y) has a probability and a confidence that depends on the counts of (X,Y) and (X, not Y). Yes, except it is not a probability in the sense of limit of frequency. This model is a simplification from a sequence of n events (with algorithmic complexity 2n) to two small integers (with algorithmic complexity 2 log n). This is your interpretation, which is fine, though I don't see why I must see it the same way, though I do agree that it is a summary of experience. The reason this often works in practice is Occam's Razor. That might not be the case if physics were not computable. Again, this is a description of your belief, not a justification of this belief. Pei --- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?member_id=8660244id_secret=117534816-b15a34 Powered by Listbox: http://www.listbox.com
Re: [agi] the universe is computable [Was: Occam's Razor and its abuse]
Matt, How about the following argument: A. Since in principle all human knowledge about the universe can be expressed in English, we say that the universe exists as a English essay --- though we don't know which one yet. B. Because of A, the ultimate scientific research method is to exhaustively produce all possible English essays, test each of them against the universe, and keep the best --- since there are infinite number of them, the process won't terminate, but it can be used as an idealized model of scientific research, and the best scientific theory will always be produced in this way. C. As a practical version of B, we can limit the length of the essay, in characters, to a constant N. Then this algorithm will surely find the best scientific theory within length N in finite time. Now everyone doing science should approximate this process as closely as possible, and the only remaining issue is computational power to reach larger and larger N. Of course, I don't mean that your argument is this silly --- the research paradigm you argued for is interesting and valuable in certain aspects --- though I do feel some similarity between the two cases. Pei On Thu, Oct 30, 2008 at 7:30 PM, Matt Mahoney [EMAIL PROTECTED] wrote: Ben, you missed my point. We use Turing machines in all kinds of computer science proofs, even though you can't build one. Turing machines have infinite memory, so it is not unreasonable to assume that if Turing machines did exist, then one could store the 2^409 bits needed to describe the quantum state of the observable universe and then perform computations on that data to predict the future. I described how a Turing machine could obtain that knowledge in about 2^818 steps by enumerating all possible universes until intelligent life is found. As evidence, I suggest that the algorithmic complexity of the free parameters in string theory, general relativity, and the initial state of the Big Bang is on the order of a few hundred bits. -- Matt Mahoney, [EMAIL PROTECTED] --- On Thu, 10/30/08, Ben Goertzel [EMAIL PROTECTED] wrote: From: Ben Goertzel [EMAIL PROTECTED] Subject: Re: [agi] the universe is computable [Was: Occam's Razor and its abuse] To: agi@v2.listbox.com Date: Thursday, October 30, 2008, 6:02 PM If I can assume that Turing machines exist, then I can assume perfect knowledge of the state of the universe. It doesn't change my conclusion that the universe is computable. -- Matt Mahoney, [EMAIL PROTECTED] 1) Turing machines are mathematical abstractions and don't physically exist 2) I thought **I** had a lot of hubris but ... wow! Color me skeptical that you possess perfect knowledge of the state of the universe ;-) ben g agi | Archives | Modify Your Subscription agi | Archives | Modify Your Subscription --- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?member_id=8660244id_secret=117534816-b15a34 Powered by Listbox: http://www.listbox.com
Re: [agi] the universe is computable [Was: Occam's Razor and its abuse]
I am not suggesting that we model the universe by an exact computation. That is impossible (as John Rose pointed out) because the computer would have to be inside the universe it is modeling. I am suggesting that Occam's Razor holds in the observable universe because the only requirement for the proof of AIXI is that the environment have a probability distribution that is computable by a Turing machine. That is the case for the laws of physics as they are currently understood. -- Matt Mahoney, [EMAIL PROTECTED] --- On Thu, 10/30/08, Pei Wang [EMAIL PROTECTED] wrote: From: Pei Wang [EMAIL PROTECTED] Subject: Re: [agi] the universe is computable [Was: Occam's Razor and its abuse] To: agi@v2.listbox.com Date: Thursday, October 30, 2008, 8:28 PM Matt, How about the following argument: A. Since in principle all human knowledge about the universe can be expressed in English, we say that the universe exists as a English essay --- though we don't know which one yet. B. Because of A, the ultimate scientific research method is to exhaustively produce all possible English essays, test each of them against the universe, and keep the best --- since there are infinite number of them, the process won't terminate, but it can be used as an idealized model of scientific research, and the best scientific theory will always be produced in this way. C. As a practical version of B, we can limit the length of the essay, in characters, to a constant N. Then this algorithm will surely find the best scientific theory within length N in finite time. Now everyone doing science should approximate this process as closely as possible, and the only remaining issue is computational power to reach larger and larger N. Of course, I don't mean that your argument is this silly --- the research paradigm you argued for is interesting and valuable in certain aspects --- though I do feel some similarity between the two cases. Pei On Thu, Oct 30, 2008 at 7:30 PM, Matt Mahoney [EMAIL PROTECTED] wrote: Ben, you missed my point. We use Turing machines in all kinds of computer science proofs, even though you can't build one. Turing machines have infinite memory, so it is not unreasonable to assume that if Turing machines did exist, then one could store the 2^409 bits needed to describe the quantum state of the observable universe and then perform computations on that data to predict the future. I described how a Turing machine could obtain that knowledge in about 2^818 steps by enumerating all possible universes until intelligent life is found. As evidence, I suggest that the algorithmic complexity of the free parameters in string theory, general relativity, and the initial state of the Big Bang is on the order of a few hundred bits. -- Matt Mahoney, [EMAIL PROTECTED] --- On Thu, 10/30/08, Ben Goertzel [EMAIL PROTECTED] wrote: From: Ben Goertzel [EMAIL PROTECTED] Subject: Re: [agi] the universe is computable [Was: Occam's Razor and its abuse] To: agi@v2.listbox.com Date: Thursday, October 30, 2008, 6:02 PM If I can assume that Turing machines exist, then I can assume perfect knowledge of the state of the universe. It doesn't change my conclusion that the universe is computable. -- Matt Mahoney, [EMAIL PROTECTED] 1) Turing machines are mathematical abstractions and don't physically exist 2) I thought **I** had a lot of hubris but ... wow! Color me skeptical that you possess perfect knowledge of the state of the universe ;-) ben g agi | Archives | Modify Your Subscription agi | Archives | Modify Your Subscription --- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?; Powered by Listbox: http://www.listbox.com --- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?member_id=8660244id_secret=117534816-b15a34 Powered by Listbox: http://www.listbox.com
