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Gil Has Never Grasped the Nature of a Simulation Model

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Tom English challenged me with this:

I say categorically, as someone who has worked in evolutionary computation for 15 years, that Gil does not understand what he is talking about. This is not to say that he is trying to mislead anyone. It is simply clear that he has never grasped the nature of a simulation model. His comments reflect the sort of concrete thinking I have tried to help many students grow beyond, often without success.

The reason for Tom’s lack of success is that he, and Darwinists in general, try to explain everything with an overly — indeed catastrophically — simplistic model. Here’s what’s involved in a real-world computer simulation:

My mathematical, computational, and engineering specialty is guided-airdrop technology. The results of my computer simulations, and their integration into the mechanics of smart parachutes, are now being used to resupply U.S. forces in Afghanistan. C-130 and C-17 aircraft can now drop payloads from up to 25,000 feet MSL, out of range of enemy small-arms, shoulder-launched missile, and RPG fire, and the payloads autonomously guide themselves to their targets within a CEP (circular error probable) of approximately 26 meters. Did I do all of this highly sophisticated mathematical and software simulation without ever having “grasped the nature of a simulation model”?

One small part of developing this technology involves mathematically and computationally simulating the descent rate of a parachute and its payload at various altitudes. This includes the following: the drag coefficient of the parachute, the chute reference area, the density of the air at various altitudes (not only determined by altitude but lapse rate — the rate at which air temperature changes with altitude), and other subtle considerations, such as the flow-field effects of the payload which changes the drag characteristics of the parachute.

If any mathematical, computational, or real-world assumptions about any of these factors are wrong, or if any unforeseen factors are left out (and what I described above represents a small percentage of what’s involved), the simulation breaks down. We do our best, but we never know for sure until we throw the thing out of an airplane, see where it lands, and tediously analyze the telemetry data recorded by the in-flight computer.

Based on these observations and computer simulations that can be tested in the real world, what confidence can anyone have that biological evolutionary computer simulations have anything to do with reality?

The answer is: none. It’s all fantasy and speculation, masquerading as science.

Comments
If it flies, the simulation was good. If it crashes, the simulation was bad. Everything else is irrelevant.GilDodgen
September 30, 2006
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DS: "It’s all well and good to model it but you still have to build the real thing to see if it works." Your reply doesn't go to the point of my post, which is that the logic of algorithmic computation (including simulation) is independent of the substrate on which it is instantiated. This is true for all computation - not just modeling and simulation (e.g. for arithmetic computations). Hence the long division algorithm of my example remains logically unchanged across the many media (pencil and paper, 99/4a, quantum computer, banks of vacuum tubes, frontal lobes, etc) on which it can be instantiated. This independence is what makes Gil's original suggestion vis mutating the hardware of a computer running an evolutionary simulation rather silly. This has been stated and illustrated many ways in this (and the previous) thread. I didn't intend the rope-log computer as an analogy to something simulated - rather, the spoof illustrates this independence of computation and the physical substrate hosting omputation. We already know that computation can be hosted by virtually any medium, and that the rope-log computer could be made to work. (Whether it would be practical is an entirely different question.)Reciprocating Bill
September 30, 2006
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recip re ropes and logs It's all well and good to model it but you still have to build the real thing to see if it works. That's how models work. You don't seem to understand that. Once you build it and it works as the model predicted then you have a working model, until then you have an untested model. Capisce?DaveScot
September 30, 2006
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John A. Davison, "I hope it gives you gas." It does.bFast
September 30, 2006
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Nice to see this thread hasn't gone off topic.StephenA
September 30, 2006
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But Bush IS a man of God who is trying to establish a democracy in the middle east and nothing Bruce Fast or anyone else can detract from that very worthwhile venture. I wish him well. How do like them apples Bruce? I hope it gives you gas. "A past evolution is undeniable, a present evolution undemonstrable." John A. DavisonJohn A. Davison
September 30, 2006
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Scientific American magazine many years ago ran an amusing story (I think it was in an April issue) in which the discovery of an isolated Polynesian island culture was reported. Explorers were mystified by the the ritual behaviors they observed: Island inhabitants pulled ropes that traversed the entire island, ropes that shifted logs from position to position in a huge, island-wide network of ropes and logs. The explorers were astonished to learn that the system performed arithmetic by very slowly executing well known computational algorithms (it has been many years since I read this; some of these details may be misremembered). This was a spoof with a serious point: although the island was imaginary, real computation could in fact be done using ropes and logs properly arranged. With a large enough rope-log system an algorithm performing, say, long division could be (slowly) executed. More importantly, the same algorithm for division yields the same result by means of the same steps when performed by a person using pencil and paper, when coded in Basic and run on TI 99/4a, when executed by a quantum computer, handled by Searle within his Chinese room, and indeed when performed "mentally" within the working memory of an individual person. The logic of the algorithm is utterly independent of the particulars of the physical substrate on which it is executed (even if that substrate is itself computationally simulated.) The point is that the logic of algorithmic computation (including simulation) is independent of the substrate on which it is instantiated. Damage to hardware occurs at a logical level removed from that at which the algorithm is expressed. Similarly, a simulation operates at a level utterly removed from the hardware that hosts the simulation. This is what some here seem not to grasp.Reciprocating Bill
September 30, 2006
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Several points of which to take note: - Neither Gil's technical accomplishments, nor his assertion that simulations are just fantasy, have no bearing on the fatal error committed in his previous post. - Stephen A.' simulation would not entail operators pushing computers through mazes on rolling tables as they ran the simulation. - The thread has seriously wandered off topic and onto the domain of prayer, while on-topic posts are (apparently) blocked by the Nixplanatory filter that governs the exchange here.Reciprocating Bill
September 30, 2006
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Michaels7, I personally have been very troubled by the American Christian communty's belief that America is somehow "in the right" with the authority of Christ himself, and its enemies are "in the wrong" with the same authority. The fact that the USA has abandoned long held values of justice as exemplified by Guantonimo bay and the "secret" CIA prisons seems to be somehow justified. The fact that the stated reason for invading Iraq, namely because of Sadam's aledged secret WMD programs, has not been validated does not seem to faze the Christian community one bit. "We support the decision of our leader. Bush is a man of God who is making righteous war on our enemies" is the cry of the religious right. I find it disgusting, horrifying, that the religious right would label this war and the actions at Guantonimo bay as "approved" by my creator.bFast
September 30, 2006
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Bfast, "Michaels7, mind if I worship the Prince of Peace, rather than claim that my side of a war is somehow divinely right?" Not at all, please read my prayer again. I did not ask for my will to be done, but the Fathers - "raise up whom You will." That includes intelligent troops that can negotiate peacefully in these regions, because wisdom is required for peace, not war. I do not link prayer only to destruction of our enemies. And my prayer is one of protection too - for all. Those drop offs guided from the C-130 go to Afghanis as well as our troops. Medicine is delivered to sick children, vaccines, food and so many other items needed to help not only protect our troops but to help the people themselves they are trying to free from oppression. If you think the Taliban do not oppress, torture, or murder and are equal to our cause and that of our troops, then we do disagree. I believe these efforts and the sacrifices our troops are making are a worthy cause and I certainly believe that most of them have a higher cause in their hearts than someone who burns down schools, indoctrinates children with hatred, oppresses and murders women for any number of fallacious reasons, and blows up civilians on purpose. Does that make our cause divine? Only the Lord can make such judgements, but my prayer is that it is in His will. When I pray the enemy does not come against the love of Christ and that He overcomes the world, I am in fact asking for His Word, His love to conquer their hearts, and not by mens weapons. When I pray against an ideology of hatred and oppression, I am praying against principalities and powers, not people, who are sheep that God calls. I pray for all people to be saved, not just Americans. This is what is in my heart. I pray for Iraqis and Afghanis to have peace for their children's future. And I hardly think myself divine after my life of debauchery, my side or this nations. But it is important to note in reading the Psalms, King David did not pray for defeat and I find it quite hard to do so myself. And from my understanding, Christ liked his music and so did His disciples as they quoted them often. One can pray for victory in many ways, without wishing harm on innocents. In truth, the love of Christ will never happen if those trapped in nations controlled by dictators or false teachers who do not allow them to hear the Living Word. One cannot come to Christ without hearing. We worship the Prince of Peace together, but He is also the Son of the Lord of Host - Captain of Armies, King of Kings, and Lord of Lords, and Healer, Counseler. He has many names. And one period of His rule will be with a Rod of Iron. Repentence is another thing altogether... and one of which I often need to do. As well as this nation needs to as well. But that is politically incorrect also :) And I have taken this post off course, so my apologies to Gil.Michaels7
September 30, 2006
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Several points of which to take note: - Gil's assertion that simulations are just fantasy, even were it true, has no bearing on the fatal error committed in his previous post. - Stephen A.' simulation would not entail operators pushing computers through mazes on rolling tables as they ran the simulation. - Whatever Gil's intended rhetorical point, he instead displayed ignorance - plain and simple - of the nature of computation and simulation that this post does nothing to correct. Scientific American magazine many years ago ran an amusing story (I think it was in an April issue) in which the discovery of an isolated Polynesian island culture was reported. Explorers were mystified by the the ritual behaviors they observed: Island inhabitants pulled ropes that traversed the entire island, ropes that shifted logs from position to position in a huge, island-wide network of ropes and logs. The explorers were astonished to learn that the system performed arithmetic by very slowly executing well known computational algorithms (it has been many years since I read this; some of these details may be misremembered). This was a spoof with a serious point: although the island was imaginary, real computation could in fact be done using ropes and logs properly arranged. With a large enough rope-log system an algorithm performing, say, long division could be (slowly) executed. More importantly, the same algorithm for division yields the same result by means of the same steps when performed by a person using pencil and paper, when coded in Basic and run on TI 99/4a, when executed by a quantum computer, handled by Searle within his Chinese room, and indeed when performed "mentally" within the working memory of an individual person. The logic of the algorithm is utterly independent of the particulars of the physical substrate on which it is executed (even if that substrate is itself computationally simulated.) The point is that the logic of algorithmic computation (including simulation) is independent of the substrate on which it is instantiated. Damage to hardware occurs at a logical level removed from that at which the algorithm is expressed. Similarly, a simulation operates at a level utterly removed from the hardware that hosts the simulation. If you don't get this, well, you don't get it.Reciprocating Bill
September 30, 2006
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Chance never played any role in either ontogeny or phylogeny. The entire evolutionary scenario was planned from beginning to end. Even extinction was part of the scenario. The vast majority of past extinctions were internally produced and had nothing to do even with the accumulation of defective genes. So it was neither bad luck nor bad genes that produced extinctions, to comment on the title of David Raup's book. Extinction was an orthogenetic, goal directed property of the evolutionary sequence. I don't expect anyone to take my views seriously but I will predict with great confidence that no one will be able to demonstrate that I am wrong. It will be, as every other of my several challenges have been, unanswered and probably even unacknowledged. Ideologues are like that don't you know. I am convinced that every aspect of phylogeny was predetermined or "prescribed" and that chance played no role in any of it. If catastrophic events had not killed the dinosaurs they would have died anyway. It was part of the program if you know what I mean. All the bizarre ones died and only the conservative crocodilia survived. The same can be said for all the other large animals of the past. Leo Berg saw this with great clarity: "The extinction of organisms is due to inner (autonomic) and external (choronomic) causes." Nomogenesis, page 407 I wish only that he had used the past tense. Let me add that the current extinction, the one that Leakey called the sixth extinction, is due entirely to the mindless insistence on the part of civilized man to deliberately destroy his own environment. I just presented a similar summary over at "brainstorms." I'll bet they will both die on the vine. How do you chance-worshipping, mutation-happy Darwimps like them green apples? I hope they give you a belly ache. I love it so! "A past evolution is undeniable, a present evolution undemonstrable." John A. DavisonJohn A. Davison
September 30, 2006
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The problem here is Gil is talking about models of the real world and programs such as Avida are just Conway's Game of Life v2.0 Now with lots of new rules and random mutation. But still a fantasy world of cellular automata not a model of reality. P.S. Somebody needs to get with Wiki and get The Sim Games on this list of digital organism simulators. The judges all agree the Sims are much more popular than Avida. DaveScot
September 30, 2006
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In general I agree that Gil has overstepped when he suggests that the computer running a simulation must in itself be subject to random mutation. StephanA: "Our enviroment is a series of, say, ten mazes, with a creature that tries to reach the center. " I suspect that you have already front-loaded. The only destination that RM+NS permits is survival. I think that any artificial "destiny" beyond survival becomes a front-loading. I think it hard, but possibly not impossible to write a truly not front-loaded simulation. I think that the landscape that must be offered to such as simulation must be the internet itself. If a program was written which reproduced itself, and which had some way of randomly being noticed by human operators, and if the human operators had the privelage of destroying any such program that "got in their way", the results would be a pretty good simulation. If such a program produced variants which became fun, and extended to start doing real-world tasks, like maybe good quality spam filtering, then I would become convinced that RM+NS can actually account for genuine complexity as seen in nature. Remember, however, that the only thing the program can do is reproduce itself with a certain small error rate. The landscape it is in must contain at least the possibility of affecting the display of the computer it is running on. Michaels7, mind if I worship the Prince of Peace, rather than claim that my side of a war is somehow divinely right?bFast
September 30, 2006
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That's you? The OPFOR guys featured your work several weeks ago in a picture essay of an actual drop run from a C-130(if memory serves well) in Afghanistan. http://op-for.com/aboutus.php Of course, they also link gratuitous Miss World competitions too, so don't get to big an ego... ;-) Congrats on a job well done Gil! Please pass along to all your workers and crew in armed services a big thanks too! well, well, allow me to intercede with a politically incorrect moment of prayer. May G_d continue to bless your work with extraordinary insight, knowledge, energy and wisdom to overcome our enemy. And may he bless all others accordingly who support our troops in this global war against oppression and ideology of hatred, that which is all things opposed to the love of Christ. For Christ overcomes the world. In Yeshua's precious name I ask, God raise up whom You will, Amen and Amen.Michaels7
September 30, 2006
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Here's my idea for a simulation that might mimic the way that RM & NS are supposed to produce new information: Our enviroment is a series of, say, ten mazes, with a creature that tries to reach the center. These mazes will consist of simply-connected mazes, and multiply-connected mazes. ( google search if you aren't sure what these kinds of mazes are ) Our 'genes' that gets mutated are the code that controls the movement of the simulated creature. Since we're simulating how information is supposed to arise in pre-existing organisms, we'll give it a starting code that guides it through the maze by 'following the left hand wall'. This will only enable it to solve the simply connected mazes, and not very efficiently (it will go down many dead ends). The fitness function will consist of counting how many moves it takes to solve each maze, and adding up the total (larger numbers mean a less fit 'organism'). Unsolved mazes are simply given a very high value (A maze is considered unsolved if it fails to complete it within that number of moves). For me, to convincingly demonstrate evolution, the resulting code would have to be able to solve the mazes the original could not, and be able to solve other new mazes. What do you guys think? Would it be a useful model of RM & NS? Would it fulfill my criteria? I predict that it won't. The most it might do is produce code that solves the simply-connected mazes more efficiently.StephenA
September 29, 2006
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josephus63 wrote:
I think Gil’s original point was that it is necessary for a simulation to be true to the full range of the possible sources and effects of random mutation and that in the natural world these act on the hardware (physical cells) at a primary level and affect the software (abstract information encoded in DNA) secondarilly.
If that is Gil's intent, he should be insisting on virtual errors in the virtual organisms (i.e. virtual hardware) and virtual mutations in their virtual genetic information (i.e. virtual software). The fact that he is asking for real mutations and errors in the hardware and software running the simulation shows that he is confusing the simulator with the simulated.Karl Pfluger
September 29, 2006
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I for one would love to see a real discussion about this. I'm a software professional myself but have no special expertise in evolutionary algorithms. I understand that it's easy to subtly inject front-loaded CSI into an algorithm and that the more sublte the front-loading is the more illusory the end result is in terms of the appearance of chance and selection having created CSI . I think Gil's original point was that it is necessary for a simulation to be true to the full range of the possible sources and effects of random mutation and that in the natural world these act on the hardware (physical cells) at a primary level and affect the software (abstract information encoded in DNA) secondarilly . Tom English balked at the suggestion that a serious simulation would need to subject itself to meta-level mutations, insisting that the modelling is an abstraction that brings the entire realm of the system being modelled into the software. I think this is right but that Gil's somewhat rhetorical point still needs to be considered. That the models themselves (albeit completely manifested in the software) must bring the full range of potential deleterious effects into the picture, in order for meaningful inferences about natural evolutionary systems to be drawn from them. My question is have there been any case studies in evolutionary computation that have reached towards the level of sophistication in modelling (in software) the full range of effects of random mutation? If so, what are they and what can be learned from them?josephus63
September 29, 2006
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Gil, You haven't addressed the criticisms that Tom, Bill and I raised in response to your last post. You said
All computational evolutionary algorithms artificially isolate the effects of random mutation on the underlying machinery: the CPU instruction set, operating system, and algorithmic processes responsible for the replication process. If the blind-watchmaker thesis is correct for biological evolution, all of these artificial constraints must be eliminated. Every aspect of the simulation, both hardware and software, must be subject to random errors.
We pointed out that your statement revealed a misunderstanding of the distinction between the simulator and the thing being simulated. You are saying that an accurate evolutionary simulation must mutate the underlying hardware and software . But this makes no more sense than arguing that your airdrop simulations are invalid unless you airdrop the computer doing the simulation, or subject the software to temperature variations. In your simulations, a virtual payload is descending through a virtual atmosphere beneath a virtual parachute, subject to virtual temperature and density variations. The computer itself need not be airdropped nor subjected to real temperatures and density variations. In exactly the same way, an evolutionary simulation subjects virtual organisms to virtual mutations and winnows them through virtual selection pressures. There is no need to subject the hardware and software to real mutations or errors. In fact, doing so defeats the purpose of the simulation by rendering its results inaccurate. Your airdrop simulations wouldn't give accurate results if the hardware and software were mutating underneath them. Why expect an evolutionary simulation to deliver accurate results under those conditions? Virtual mutations belong in an evolutionary simulation, but real mutations to the underlying hardware and software do not.Karl Pfluger
September 29, 2006
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While those credentials are all well and good, they don't do much to address the substance of the criticisms levelled in the comments of the previous topic.Tiax
September 29, 2006
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