Only a theory

Another talk about science and religion in contemporary Islam to an audience with a high percentage of Muslims, another encounter with the “evolution is only a theory” meme. Sigh.

This time it was a hijab-wearing Iranian student. She asked what the problem would be if Muslim scientists were to favor alternatives to evolution. After all, it’s only a theory, isn’t it? As I understood it, the implication of the question was that disputes about theory shouldn’t matter too much, and that scientists should deal with hard facts.

This isn’t just a problem of being misinformed about how “theory” as a scientific term differs from the colloquial equivalent of a mere guess. It’s hard for anyone without a close acquaintance with natural science to appreciate the role theories play in doing science. Without close interaction and mutual correction between theory and experiment, you simply do not have a mature science. Theory is not optional to scientific activity. It’s not something you can brush away if it doesn’t appeal to your religious sensibilities.

It is especially galling that people who dismiss theory very often do so in favor of religious convictions that, by scientific standards, typically do not even rise to the level of being a respectable mistake.

Beh.

About Taner Edis

Professor of physics at Truman State University

  • http://www.blogger.com/profile/09891160904748206385 AYDIN ÖRSTAN

    The next time someone tells you that evolution is only a theory, try reminding the person that his/her religious beliefs are also only a theory.

  • http://www.blogger.com/profile/09925591703967774000 Dianelos Georgoudis

    There is certainly much misunderstanding or ignorance of the theory of evolution in some religious circles, and this is unfortunate. On the other hand I would like to point out that at least part of the problem is that some atheists are overselling Darwinism and are therefore partially responsible for the over the top reaction on the other side. For example here is what Richard Dawkins (who, being a specialist in the field, should know better) said in his recent discussion with Bishop Harries (the video is available on youTube at http://tinyurl.com/d2qaf4 – the part I quote is from about minute 26):

    RD: Let’s look at what Darwin actually did. Darwin showed that you can get complexity, you can get brains, eyes, wings, intestines, hearts – you can get all these wonderful, beautiful, complex things starting from almost nothing, starting from molecules in the primeval soup [inaudible] going back before that. That’s a stupendous feat of explanation, that’s what Darwin did.

    In fact Darwinism explains the evolution of the species starting not with a primeval soup of just molecules, but with a primeval soup of viable biological organisms, able to replicate etc, and that’s far from “almost nothing”. Arguably there is much larger jump in functional complexity between inanimate matter and the first biological organism, than between that organism and the species as we know them; and Darwinism only applies to the second jump. The question of how life itself evolved for Darwinism to take hold is an as yet unanswered scientific question, and the answer when it comes will probably have little to do with Darwinism.

    Even overlooking this point, we still don’t have “almost nothing”. After all Darwinism does not only require inheritance, random mutation, and natural selection – but requires these in the right measure in the appropriate environment. For example either too much or too little random mutation and the Darwinian mechanism does not work. Indeed it’s far from simple to implement the Darwinian algorithm in a piece of software; quite some teleological thought must go into it.

    Further we now know that part of the explanation of the evolution of the species lies in mechanisms unknown to Darwin such as genetic drift (and perhaps autocatalytic sets also). So it’s not like Darwinism by itself explains the evolution of the species.

    But let’s take the current state of scientific knowledge, and ignore Dawkins’s claim that it’s just Darwinism and that it all starts from “almost nothing”. Do we now have a scientific explanation for our own evolution? Obviously not, for the greatest and more relevant fact that pertains to us, namely our consciousness, is not explained. Darwin’s buddy Thomas Huxley was an epiphenomenalist and believed that consciousness just happens in our brain without any causal effect whatsoever. If so the evolution of consciousness cannot be explained by any biological account of evolution. What’s a fact is that today there is far from scientific consensus of how consciousness is produced by a physical system. Or even about what consciousness actually is. Or even about whether these are scientific questions in the first place.

    But let’s forget the issue of consciousness too and only concentrate on the objectively observable aspects of us: our complex bodies and behavior, including our intelligence. Are we at least now justified to claim that science today explains our evolution starting from such and such simple beginnings? I thought the answer was yes, but I am now reading Keith Ward’s “God, Chance & Necessity” and I am no longer that sure. His argument as I understand it is this: An explanation of how physical state A evolved into state B is valid if and only if given A there is a good probability that B will result. In our case A is the Earth with its primitive life forms a few billion years ago and B is the Earth with life as complex as it now is. He claims that there is no implicit pointer in the current scientific understanding towards ever greater complexity, and certainly not towards the complexity required for human-level intelligence (intelligence strong enough to allow an organism who possesses it to dominate the entire planet). He argues that based on all we know about science the evolution of B with such complex organisms through naturalistic processes is very highly unlikely, at least according to the current state of knowledge. Therefore the current scientific theories as Dawkins understands them, namely as describing a fully naturalistic process, do not offer an explanation for B.

    Now let’s be careful about what Keith Ward is saying here. He is not attacking the idea that humankind is the result of just the biological processes that science describes; rather he attacks the naturalistic claim that these processes are unguided, a claim that strictly speaking goes beyond the science. If his analysis is correct then arguably the science increases the probability of God by making the evolution of humankind via an unguided biological process highly unlikely. At this juncture Keith Ward concedes that it is possible that in the future it will be shown that the laws and facts of physics are finely tuned in a way that makes the evolution of intelligence bearing complex life probable after all. But in this case the problem for naturalism has only been moved from the improbability of the unguided biological processes to the improbability of the underlying physical laws and facts.

    It seems Keith Ward’s argument is based on Arthur Peacocke’s “Theology for a Scientific Age”, but not having read this latter book I am not sure. I note that Arthur Peacocke was not only a theologian by a biochemist too. I don’t myself know what to make of the argument above. It’s a fact that an unguided Darwinian algorithm is very powerful by itself and will normally increase complexity up to some degree at least. Any comments?

  • http://www.blogger.com/profile/13562135000111792590 RBH

    Dianelos Georgoudis wrote

    In fact Darwinism explains the evolution of the species starting not with a primeval soup of just molecules, but with a primeval soup of viable biological organisms, able to replicate etc, and that’s far from “almost nothing”.

    and then later:

    For example either too much or too little random mutation and the Darwinian mechanism does not work.

    Those are examples of a couple of fundamental misunderstandings. The relevant variable is not “to much or too little random mutation,” it is “variable robustness of the heritable element(s) to copy errors.” Mutation rates are the product of an interaction between the fidelity of the copying mechanism (which varies) and environmental mutagens (radiation, etc.). Robustness in the face of copy errors and mutagens (which determine mutation rates) is itself evolvable by Darwinian mechanisms.

    So all that’s required is a population of replicators (they could be organic molecules) with heritable variation (including variation in robustness with respect to mutation) in an environment with limiting resources of one sort or another (yielding competition and natural selection).

    Dianelos Georgoudis wrote

    The question of how life itself evolved for Darwinism to take hold is an as yet unanswered scientific question, and the answer when it comes will probably have little to do with Darwinism.

    “How life itself evolved”? Evolution is “Darwinian.” How life in the sense of replicating populations of entities with heritable variation first emerged is not a problem in evolution, and thus probably won’t have much of anything to do with “Darwinism.” However, it will have to do with naturalistic geochemical and biochemical processes.

    Dianelos Georgoudis wrote

    Indeed it’s far from simple to implement the Darwinian algorithm in a piece of software; quite some teleological thought must go into it.

    On the contrary, it’s trivially easy. One can write an evolutionary algorithm in double-digit minutes. What’s difficult is to create an evolutionary algorithm to solve some particular applied problem, and there most of the difficulty lies in figuring out what the fitness function should be. But biological evolution doesn’t have that problem since it’s not trying to solve any particular problem.

    Dianelos Georgoudis wrote

    Further we now know that part of the explanation of the evolution of the species lies in mechanisms unknown to Darwin such as genetic drift (and perhaps autocatalytic sets also). So it’s not like Darwinism by itself explains the evolution of the species.

    Um, if you’re using “Darwinism” in the sense of “what Darwin wrote in 1859″ then you’re merely flogging a strawman. No one argues that what Darwin thought in 1859 is a complete explanation. Dawkins is British, and Brits tend to use the term “Darwinism” to refer to modern evolutionary theory, not to the 1859 version of it.

    Dianelos Georgoudis’ remarks about consciousness are all of the form “We don’t understand something yet, so we won’t ever be able to understand it.” In the absence of some reason to believe it is in principle impossible to know, that’s a specious argument.

    Keith Ward’s argument, as Dianelos Georgoudis presents it, is

    He claims that there is no implicit pointer in the current scientific understanding towards ever greater complexity, and certainly not towards the complexity required for human-level intelligence (intelligence strong enough to allow an organism w

    But that’s factually false. Complexity via standard naturalistic processes is easy to come by in a physical and biological environment that is high-dimensioned, and those environments are high-dimensioned. Every speciation event, by increasing the complexity of the biological environment, increases the complexity of the selective environment for all the populations in that environment. Complexity increase in biological populations is a bootstrapping process.

    And the probability argument about A leading to B is valid if and only if B is the sole member of the class of outcomes that are functionally comparable. We don’t know that to be the case. In fact, giving the instances of convergent evolution we do know about we’re pretty sure it’s not the case. So 1 over some big number is not the relevant probability. Ward is merely repeating the mistakes of bog-standard creationists in their mis-application of probabilities.

    Dianelos Georgoudis inteprets Keith Ward as implying,

    If his analysis is correct then arguably the science increases the probability of God by making the evolution of humankind via an unguided biological process highly unlikely.

    It also makes the evolution of squidkind via unguided biological processes highly unlikely, and the evolution of tapewormkind via unguided biological processes highly unlikely, and on and on. The argument is specious in every case.

    And, of course, it’s not God who is doing any guiding that might be needed, it’s really Ba’al, or maybe Huracan. Find a pointer to the Judeo-Christian God in any of those “unlikely” premises? I don’t. There’s some heavy duty question-begging going on there.

  • http://www.blogger.com/profile/09925591703967774000 Dianelos Georgoudis

    RBH wrote: Robustness in the face of copy errors and mutagens (which determine mutation rates) is itself evolvable by Darwinian mechanisms.

    I agree that once the Darwinian mechanism starts mutations rates can be optimized by it. My point was that for Darwinian mechanism to start in the first place the mutation rates must lie within a limited range of values. Remember that I was arguing against Dawkins’s claim that the Darwinian mechanism requires “almost nothing”, and using it as an example of how some naturalists are overselling Darwinism and are therefore responsible for the over the top contrary response.

    RBH wrote: So all that’s required is a population of replicators (they could be organic molecules) with heritable variation (including variation in robustness with respect to mutation) in an environment with limiting resources of one sort or another (yielding competition and natural selection).

    Does Darwinism explains how a population of replicating organic molecules under the conditions you describe would evolve into the first biological organisms? I think not. If I am right then the claim that Darwinism starts with a soup of particular molecules is very misleading.

    To my claim that “it’s far from simple to implement the Darwinian algorithm in a piece of software; quite some teleological thought must go into it”, RBH wrote: On the contrary, it’s trivially easy. One can write an evolutionary algorithm in double-digit minutes. What’s difficult is to create an evolutionary algorithm to solve some particular applied problem, and there most of the difficulty lies in figuring out what the fitness function should be. But biological evolution doesn’t have that problem since it’s not trying to solve any particular problem.

    I am not talking about writing software which implements the bare bones evolutionary algorithm in the abstract (which can indeed be written fairly quickly), nor about the other extreme of using the evolutionary algorithm to solve some particular problem. Rather I am talking about setting up the evolutionary algorithm so that something interesting happens, such as the production of organisms that appear to be of increasing morphological complexity. Richard Dawkins has tried to do that (see his “biomorph” program ) and had to resort to implement the fitness function by observing the organisms and manually choosing which ones should survive. So he actually failed to implement the Darwinian algorithm, which shows that it can’t really be “trivially easy” to do so. My point then that for the evolutionary algorithm to evolve complex organisms reality must fulfill special requirements stands, contrary to Dawkins’s affirmation that the Darwinism requires “almost nothing”.

    RBH wrote: Dianelos Georgoudis’ remarks about consciousness are all of the form “We don’t understand something yet, so we won’t ever be able to understand it.” In the absence of some reason to believe it is in principle impossible to know, that’s a specious argument.

    Well, the mind-body problem is not just some gap. Consciousness if after all the defining fact of our condition, and is the space where we find all data on which we base our beliefs. That naturalism does not offer any idea whatsoever of how or why consciousness should emerge is a major problem. Not to mention that good arguments exist which show that consciousness cannot be explained on materialistic principles (see for example the thought of David Chalmers). Here is another argument in the same direction: 1) Consciousness is not an objectively observable phenomenon [premise]; 2) Science can only explain objectively observable phenomena [premise]; 3) Therefore science cannot explain consciousness [from 1 and 2]; 4) Scientific naturalism cannot explain more than what science explains [premise]; 5) Therefore scientific naturalism cannot explain consciousness [from 3 and 5].

    I had written “[Keith Ward] claims that there is no implicit pointer in the current scientific understanding towards ever greater complexity, and certainly not towards the complexity required for human-level intelligence” to which RBH responds: But that’s factually false. Complexity via standard naturalistic processes is easy to come by in a physical and biological environment that is high-dimensioned, and those environments are high-dimensioned. Every speciation event, by increasing the complexity of the biological environment, increases the complexity of the selective environment for all the populations in that environment. Complexity increase in biological populations is a bootstrapping process.

    Yes, biological evolution once it starts will tend to increase the complexity of the organisms. But one can easily imagine environments where after a point any further increase of complexity decreases fitness, so that the biosphere would stabilize at a fairly low level of complexity. Similarly, subsequent changes in the environment may actually result in a decrease of that complexity. The way I see it, there is clearly an evolutionary niche for organisms complex enough to possess human level intelligence (HLI). The question is how probable it is that the Darwinian mechanism once started on a planet will be able to reach that niche. For example, perhaps it is the case that if a freak celestial event had not wiped out the dinosaurs HLI would never have evolved on Earth. The broader question is this: Given our universe with its initial conditions, laws, and constants: how probable is it that organisms with HLI would evolve somewhere in it? I think that’s a valid scientific question, and one that deserves some study.

    My own position is that the theistic preoccupation with Darwinism is an unfortunate distraction for it is really next to irrelevant (a very many physical phenomena can me modeled on mechanical principles; why shouldn’t the phenomenon of life and of intelligent behavior be amenable to such modeling too?). On the other hand Keith Ward has succeeded in planting a doubt in my mind and I would like to see that doubt dealt with. My own guess is that the probability of HLI evolving in our universe is not extremely low. On the other hand, the fact that our universe should be so quiet instead of swarming with the life of civilizations that started out much earlier than ours is kind of unnerving. One way or the other, as things stand today, to say that Darwinism explains the emergence of HLI is simply a gross exaggeration: Darwinism does not explain the emergence of life in the first place, and to my knowledge it has not shown that once life starts on a planet like Earth the evolution of HLI is probable.

    RBH wrote: And, of course, it’s not God who is doing any guiding that might be needed, it’s really Ba’al, or maybe Huracan.

    Perhaps, but if science were to show that the probability that HLI would evolve in our universe by unguided natural processes is very low then naturalism as we know it would be falsified for all practical purposes. The name or attributes of the guiding supernatural intelligence would be quite irrelevant.

  • http://www.blogger.com/profile/13562135000111792590 RBH

    Dianelos Georgoudis wrote

    I agree that once the Darwinian mechanism starts mutations rates can be optimized by it. My point was that for Darwinian mechanism to start in the first place the mutation rates must lie within a limited range of values.

    But once again, “mutation rate” is not a primitive; it’s the result of the interaction of the variation in the copying fidelity of the entities in a population (or multiple populations) and the extrinsic mutagenic variables operating in the environment. So the accurate statement is that “mutation rates for some proportion of the replicators must lie with a limited range of values.” Hence there will inevitably be variation in mutation rates, and that’s the wedge required for Darwinian evolution to operate.

    Dianelos Georgoudis asked

    Does Darwinism explains how a population of replicating organic molecules under the conditions you describe would evolve into the first biological organisms? I think not. If I am right then the claim that Darwinism starts with a soup of particular molecules is very misleading.

    Not yet. But that’s not a statement that natural processes (“Darwinism”) cannot in principle explain it. The first move in any scientific research program is to attempt to explain phenomena in terms of existing theory. Finding a new planet orbiting in a strange configuration, we don’t automatically say “That can’t be explained by Newtonian or Einsteinian mechanics.” Rather, we do the research necessary to test whether we are missing variables, missing other planets, or don’t know other details that in conjunction with existing theory can explain the behaviour.

    There are active research programs aimed at exactly that question, and we know bits and pieces of parts of the process. That we don’t know everything is not a statement that we don’t know anything.

    Dianelos Georgoudis wrote

    I am not talking about writing software which implements the bare bones evolutionary algorithm in the abstract (which can indeed be written fairly quickly), nor about the other extreme of using the evolutionary algorithm to solve some particular problem. Rather I am talking about setting up the evolutionary algorithm so that something interesting happens, such as the production of organisms that appear to be of increasing morphological complexity.

    So he [Dawkins] actually failed to implement the Darwinian algorithm, which shows that it can’t really be “trivially easy” to do so. My point then that for the evolutionary algorithm to evolve complex organisms reality must fulfill special requirements stands, contrary to Dawkins’s affirmation that the Darwinism requires “almost nothing”.

    That’s the same error that those who claim that Darwin’s invocation of artificial selection as an analogy for natural selection merely illustrates that ‘natural’ selection requires a ‘Selector.’

    There are evolutionary simulation programs that do in fact evolve complex ‘organisms’ — entities composed of computer code — that have very different phenotypes than did their ancestors. Don’t fixate on Dawkins’ work of 30 years ago as your example of what has and has not been done in evolutionary computing. See here for one recent example. There are many more.

    Dianelos Georgoudis wrote

    Yes, biological evolution once it starts will tend to increase the complexity of the organisms. But one can easily imagine environments where after a point any further increase of complexity decreases fitness, so that the biosphere would stabilize at a fairly low level of complexity. Similarly, subsequent changes in the environment may actually result in a decrease of that complexity.

    Notice that you have shifted the argument. Initially, it was “Therefore the current scientific theories as Dawkins understands them, namely as describing a fully naturalistic process, do not offer an explanation for B” where B “is the Earth with life as complex as it now is,” and the “naturalistic process” in question is Darwinian evolution. Now you have shifted the basis of the argument to properties of the selective environment, not the process operating in that environment.

    Sure, one can imagine such environments. The question is whether they dominate the distribution of all environments, particularly in light of the bootstrapping character of evolution. And sure, once some level of complexity has evolved, it’s possible for one or another population to decrease its complexity, while others increase. Ward’s “highly unlikely” is a probability statement where neither the numerator nor denominator (if we’re using frequentist probability) is known. If we’re using Bayesian likelhood estimates then a lot depends on one’s priors. Does Ward defend his priors?

    Dianelos Georgoudis wrote

    If his analysis is correct then arguably the science increases the probability of God by making the evolution of humankind via an unguided biological process highly unlikely.

    And it increases the probability (again, what kind of probability?) of the 99 creator gods listed here, and more. I much prefer my Multiple Designers Theory. :)

    Finally, Dianelos Georgoudis wrote

    On the other hand, the fact that our universe should be so quiet instead of swarming with the life of civilizations that started out much earlier than ours is kind of unnerving.

    Ah, yes. Fermi’s paradox. That’s also bothered me over the years. Coincidentally, the other day I was re-reading a science fiction novel by Poul Anderson, The Boat of a Million Years, in which Anderson gives a nice resolution of Fermi’s paradox phrased in terms of the diminishing marginal gains in new information of galactic exploration. Anderson also explained a potential flaw in the population dynamics assumed by the paradox. I won’t describe it further here, but it seemed plausible, at least.

  • http://www.blogger.com/profile/09925591703967774000 Dianelos Georgoudis

    I asked whether Darwinism explains how a soup of replicating organic molecules evolved into the first biological organisms, to which RBH wrote: Not yet. But that’s not a statement that natural processes (“Darwinism”) cannot in principle explain it.

    First of all I don’t think it’s a good idea to equate “Darwinism” with “natural processes”, because lots of natural processes have nothing to do with Darwinism. And to guess that Darwinism may in principle be able to explain the evolution of life out of a soup of replicating molecules is very far from claiming that Darwinism does explain it. Let’s not forget my original argument in this discussion, namely that by overselling Darwinism some naturalists are partially responsible for the misguided contrary response in the theistic side. As a case in point I quoted respected scientist Richard Dawkins saying: “Let’s look at what Darwin actually did. Darwin showed that you can get complexity, you can get brains, eyes, wings, intestines, hearts – you can get all these wonderful, beautiful, complex things starting from almost nothing, starting from molecules in the primeval soup.” I think we agree that what Dawkins here says is factually wrong, and what bothers me is that Dawkins should know better because that’s his field. – Incidentally my own guess is that when science explains how the first biological organisms emerged the answer will be centered on mechanisms other than Darwinism.

    Thanks for the link to the recent paper in Nature about the evolutionary origin of complex features. Quite interesting. But I think it supports my claim that the Darwinian algorithm needs quite some teleological work before it produces complexity thus belying Dawkins’s claim that the Darwinian evolution of the species started “from almost nothing”.

    RBH wrote: “Now you have shifted the basis of the argument to properties of the selective environment, not the process operating in that environment.”Well, both are relevant. Please observe that the Darwinian algorithm is not a property of our physical universe, but is a mathematical property. To put it in other words the Darwinian algorithm exists in all possible worlds. The question is how probable it is that a physical universe will be such that the Darwinian algorithm will increase complexity in it to some significant degree. For this both the physical processes which operate in this universe (i.e. the physical laws and constants) and the actual physical environment are relevant.

    RBH wrote: “Ward’s ‘highly unlikely’ is a probability statement where neither the numerator nor denominator (if we’re using frequentist probability) is known. If we’re using Bayesian likelhood estimates then a lot depends on one’s priors. Does Ward defend his priors?”No he doesn’t, but his argument is based on biochemist Arthur Peacocke’s work, and perhaps he does. In any case where’s the onus of proof here? It’s naturalists who claim that given the physical facts of our universe unguided evolution explains the emergence of the complexity required for human level intelligence, so it seems to me it’s naturalists who have to show that this is indeed probable. Ward’s qualitative arguments are quite successful in creating a reasonable doubt about this. Indeed there is the widespread impression that as long as Darwinian processes operate on a planet they will produce ever increasing complexity, and Ward shows that this is not so.

    RBH wrote: “Ah, yes. Fermi’s paradox. That’s also bothered me over the years. Coincidentally, the other day I was re-reading a science fiction novel by Poul Anderson, The Boat of a Million Years, in which Anderson gives a nice resolution of Fermi’s paradox phrased in terms of the diminishing marginal gains in new information of galactic exploration. Anderson also explained a potential flaw in the population dynamics assumed by the paradox. I won’t describe it further here, but it seemed plausible, at least.”There are other solutions. One is that human level intelligence is so rare that it is unlikely to have evolved anywhere else in the universe. Another is that intelligent races quickly self-destroy their biosphere the way some diseases always kill their host. Another is that intelligent races quickly turn into genuine religion and create a pastoral society dedicated in spiritual and not material growth.

  • http://www.blogger.com/profile/13562135000111792590 RBH

    Dianelos Georgoudis wrote

    First of all I don’t think it’s a good idea to equate “Darwinism” with “natural processes”, because lots of natural processes have nothing to do with Darwinism. And to guess that Darwinism may in principle be able to explain the evolution of life out of a soup of replicating molecules is very far from claiming that Darwinism does explain it.It’s not a “guess,” it’s an educated conjecture. A “soup of replicating molecules” is very likely to have the initial conditions required by evolution by natural selection (“Darwinian” processes): (1) a population of fecund imperfect replicators, with (2) heritable variation, in (3) an environment with at least one limiting resource (where “fecund” means replicating at a rate greater than that required for a constant population). Under those conditions, “Darwinian” evolution will occur.

    Dianelos Georgoudis wrote

    Thanks for the link to the recent paper in Nature about the evolutionary origin of complex features. Quite interesting. But I think it supports my claim that the Darwinian algorithm needs quite some teleological work before it produces complexity thus belying Dawkins’s claim that the Darwinian evolution of the species started “from almost nothing”.What “teleological work” is indicated in that paper?

    Dianelos Georgoudis wrote

    Please observe that the Darwinian algorithm is not a property of our physical universe, but is a mathematical property. To put it in other words the Darwinian algorithm exists in all possible worlds. The question is how probable it is that a physical universe will be such that the Darwinian algorithm will increase complexity in it to some significant degree.I agree, but my remarks on probability are again relevant: We do not (and possibly can not) know that probability.

    I have read some Peacocke, and as far as I can tell his view view is reasonably represented in Chapter 3 here. I do not recall him ever mentioning priors; as far as I know, to the extent that he wrote about probability, he was using it in a frequentist sense.

    Dianelos Georgoudis wrote

    In any case where’s the onus of proof here? It’s naturalists who claim that given the physical facts of our universe unguided evolution explains the emergence of the complexity required for human level intelligence, so it seems to me it’s naturalists who have to show that this is indeed probable.And I’d say it was the supernaturalists who bear the burden of proof. The naturalist says “No phenomena that we have come to understand via the methods of science have required non-natural (supernatural) causal agency. If you think one is required, show me.”

    Even in the cases where the scientists were themselves theists of varying flavors and intensity, none have found it necessary to invoke supernatural or teleological causal agents in the domains where they provided naturalistic explanations. Only when they reached the boundaries of their ability to explain something did they invoke supernatural agency. Newton didn’t invoke supernatural agency in his mechanics, unitarian theist though he was. But those boundaries are pushed back by the next generation, and the solar system that seemed to Newton to require divine intervention to maintain its stability is now understood to be stable on the time scales of interest via purely natural processes.

    Dianelos Georgoudis wrote

    Indeed there is the widespread impression that as long as Darwinian processes operate on a planet they will produce ever increasing complexity, and Ward shows that this is not so.I’m going to have to read Ward, I guess. The circumstances under which evolutionary processes will not operate to produce increased complexity (though “ever increasing” may be a stretch) seem to me to be the less frequent case. There are fitness landscapes on which evolutionary processes are not effective — absolutely flat fitness landscapes and random fitness landscapes — but in the vast middle ground where local autocorrelations on the landscape are non-zero the evolutionary algorithm will operate, albeit with greater or lesser efficiency depending on the particular statistical properties of that landscape. And bear in mind that a substantial portion of the selective environment of a population is other biological populations. Co-evolution is a powerful driving “force” in evolution. The more different populations, the more complex the selective environment and the more complex the adaptations to it.

    Whether evolutionary processes will inevitably produce entities of “ever increasing complexity” is questionable. Complexity does not come without paying a price, and that price increases with increasing complexity. So there’s a tension — a reproductive fitness tug of war — between the selective advantages associated with increased complexity, if any, and the costs of the complexity in mechanical, structural, and metabolic terms.

    I myself have not seen it claimed that evolutionary processes will inevitably generate “ever increasing complexity.” However, that those processes can produce the levels of complexity we see in the extant biological world is a settled matter: It can. While we don’t know everything, we know enough to assert that as a strongly corroborated claim. There are remaining problems — consciousness prominent among them — but I see no reason to suppose that there is a qualitative leap that requires a supernatural explanation.

    On resolutions of the Fermi paradox, Dianelos Georgoudis wrote

    Another is that intelligent races quickly self-destroy their biosphere the way some diseases always kill their host. Yup, and in my gloomier moments that’s the one I favor. It is by no means settled that human-level intelligence is a long-term adaptive trait.

  • http://www.blogger.com/profile/13562135000111792590 RBH

    Testing paragraphing in this damned comment mediumStill testing paragraphing with no space continuation.

    Another testWith single space continuation.

    One more test of paragraphing.And the last one with double-space continutation.

    Taner, you can delete this if you wish. Thanks!

  • http://www.blogger.com/profile/09925591703967774000 Dianelos Georgoudis

    RBH wrote: “It’s not a ‘guess,’ it’s an educated conjecture.” An educated conjecture is still a guess. The process by which the first live cells emerged from inanimate matter is still an unanswered scientific question, and when trusted scientists speak as if the solution is known (and is Darwinian at that) then they are overselling the facts and truth is not served.

    RBH wrote: “What ‘teleological work’ is indicated in that paper?”Well, obviously quite a bit of work went into making the simulation evolve complex features (in this case programs able to perform logic functions), which was the goal of the exercise. The simulation itself implemented the Darwinian algorithm, but the parameters of the simulation were set up purposefully with a particular goal in mind. Hence this paper describes the result of teleological work.

    I suppose the deeper question is what “design” means. I have never myself employed the Darwinian algorithm to solve a problem, but I have used a dumb hit and miss algorithm to create a number of hash functions I needed. What I did was I used a pseudo-random number generator to produce short assembly language programs and then automatically checked how well they performed a hash function. After a large number of trial programs (into the hundred of millions if I recall correctly) I picked the 32 best performers. I had a short look at one of them trying to understand why it was so good at hashing, but did not get very far. Now the question is: Did I design these hash functions or not?

    RBH wrote: “I agree, but my remarks on probability are again relevant: We do not (and possibly can not) know that probability.”But until we do know the probability that the complexity required for human level intelligence would evolve based on unguided Darwinian processes the naturalistic claim that the evolution of humanity in our universe can be explained on mechanical principles alone will remain unwarranted.

    Actually there are two questions implicit here: What is the probability that in our physical universe HLI would evolve unguided? What is the probability that in some physical universe HLI would evolve unguided (perhaps our universe is fine-tuned for the natural evolution of intelligence too)? One way or the other these are interesting scientific questions, and I don’t personally see why future science shouldn’t be able to answer them, especially considering the computational resources that scientists in the future will have at their disposal.

    If science demonstrates that HLI is not improbable and that therefore it could be the case that our biological bodies are the result of unguided evolution then the question would remain whether they in fact are. After all if theism is true then they need not be and probably aren’t. So at best science can only demonstrate that naturalism lacks one particular internal problem. (Incidentally here I mean probabilities in the frequentist sense: If one would start a mechanical universe of the kind ours is – the same initial state, laws, and constants – then in which proportion of the resulting worlds would HLI evolve.)

    Recently I heard a taped lecture by Daniel Dennett where he explained evolution. He was so happy describing his cranes, and how nature blindly searches the design space and finds really smart solutions, and how in pre-historical times our brains were invaded by self-replicating memes with which we keep a mutualistic symbiosis ever since, and so on. He kept repeating how wonderful it all was, and I found myself agreeing with him. Which made me realize this: The naturalist sees the deep order in the physical phenomena we observe and thinks that this demonstrates the non-existence of God. The theist sees the same deep order and thinks that on the contrary this demonstrates the existence of God. Depending on one’s ontological preconceptions then the same evidence can lead to opposing metaphysical conclusions.

    RBH wrote: “I’m going to have to read Ward, I guess. The circumstances under which evolutionary processes will not operate to produce increased complexity (though ‘ever increasing’ may be a stretch) seem to me to be the less frequent case.”I meant “ever increasing” up to the high level of complexity required for HLI (they say that our brain is the most complex object in the universe).

    RBH wrote: “There are fitness landscapes on which evolutionary processes are not effective — absolutely flat fitness landscapes and random fitness landscapes — but in the vast middle ground where local autocorrelations on the landscape are non-zero the evolutionary algorithm will operate, albeit with greater or lesser efficiency depending on the particular statistical properties of that landscape. And bear in mind that a substantial portion of the selective environment of a population is other biological populations. Co-evolution is a powerful driving “force” in evolution. The more different populations, the more complex the selective environment and the more complex the adaptations to it.”Yes. And the stability of the environmental parameters of the fitness landscape may be an additional important factor; too much or too little may limit the maximal complexity that can be reached. For really impressive results perhaps mighty catastrophes of the kind that have visited our planet several times throughout its evolutionary history may be necessary, for they suddenly and radically changed the entire landscape thus perhaps opening avenues for evolution to be taken advantage of by species which survive.

    RBH wrote: “However, that those processes can produce the levels of complexity we see in the extant biological world is a settled matter: It can.” (I assume by “processes” you mean naturalistic, i.e. mechanical and unguided, processes.)

    My hunch is that they can, but I disagree about this being a settled matter. I think that you are improperly using the anthropic principle. The fact that we are here proves of course that reality is such as for our existence to come about, but unless naturalism is true this same fact says nothing about whether we came about through mechanical means, as naturalism has it. And of course naturalism is not given, so the matter cannot be settled so easily.

  • http://www.blogger.com/profile/13562135000111792590 RBH

    Dianelos Georgoudis wrote

    An educated conjecture is still a guess. The process by which the first live cells emerged from inanimate matter is still an unanswered scientific question, and when trusted scientists speak as if the solution is known (and is Darwinian at that) then they are overselling the facts and truth is not served. OK, I’ll concede that if one implies or states that the answer is known, that’s an overstatement. But at this stage of the game we’re not completely ignorant. We know something about how vesicles can form, and how relatively simple organic molecules can form, and more along the lines of bits and pieces. But it’s true we don’t at all know the whole story.

    Dianelos Georgoudis wrote

    Well, obviously quite a bit of work went into making the simulation evolve complex features (in this case programs able to perform logic functions), which was the goal of the exercise. The simulation itself implemented the Darwinian algorithm, but the parameters of the simulation were set up purposefully with a particular goal in mind. In that same sense, every experiment in the world involves a great deal of “teleological work.” But the outcome in that particular set of experiments was by no means assured. The goal of the experiment was to determine whether complex features would evolve by the purely mechanistic processes invoked by evolutionary theory in an environment where acquiring complex features is reproductively advantageous. As it turns out, they do. That’s why Nature published it.

    Your example of producing the hash functions is akin to artificial selection, horticulture. Plant a large field of seeds and selection the variants you want. So the answer is that you did not “design” them, for all reasonable semantic values of “design.”

    Dianelos Georgoudis wrote

    But until we do know the probability that the complexity required for human level intelligence would evolve based on unguided Darwinian processes the naturalistic claim that the evolution of humanity in our universe can be explained on mechanical principles alone will remain unwarranted.Well, I myself don’t take it as a claim that it can be explained by mechanical processes. Rather, I take it as a working hypothesis or working assumption made so I can do science. Absent that working assumption one goes home and tends one’s garden rather than doing science. And there’s some pretty powerful warrant for making that working assumption, namely three centuries of success in explaining, understanding, predicting, and controlling physical processes in the world, as contrasted with multiple millenia of failure on the supernaturalists’ part.

    Future science may be able to answer the two questions you pose. My point has been that we cannot even make an estimate of the probabilities now, so invoking them, as in ‘It’s too improbable to have occurred by unguided natural processes,’ is worse than a waste of time: it pretends we know stuff we don’t know and is thus actively misleading.

    Describing Dennett’s exuberance, Dianelos Georgoudis wrote

    The naturalist sees the deep order in the physical phenomena we observe and thinks that this demonstrates the non-existence of God. No, this naturalist thinks that it demonstrates the non-necessity of God. As Laplace is reputed to have told Napoleon, when asked what role God played in controlling celestial phenomena, ‘I had no need of that hypothesis.’ God is superfluous, at least in explaining natural phenomena.

    That’s all I have time for now. Sorry.

  • http://www.blogger.com/profile/09925591703967774000 Dianelos Georgoudis

    RBH wrote: ” In that same sense, every experiment in the world involves a great deal of “teleological work.”The way I see it the typical scientific experiment is like asking nature a question, whereas here we have a case where they wanted to demonstrate that something works, or that a particular methodology works. This looks more like an engineering project to me. Observe that how they defined parameters such as the energy gain for the various logical functions served a particular *purpose* they had in mind, namely to have organisms evolve the capability of performing complex functions, so they gave more gain to the more complex functions. Come to think of it by doing this they may have jury rigged the result though, thus negating the whole exercise. My problem with this particular paper is that the “complex function” which evolved through Darwinian processes (i.e. the EQU function) is really very simple, and one wonders whether the authors may have not themselves put in more intelligence in the system than came out of it. It would have been more impressive if they had evolved mathematician organisms able to prove theorems within some formal system, or something like that.

    Incidentally the “Avida” platform they used would correspond to what Dawkins called “almost nothing”. Virtually all the work they did for that paper then would correspond to what I call “teleological work”.

    RBH wrote: ” As it turns out, they do.”

    Was there really any doubt about this? Incidentally, the hash functions I created through mechanistic means are orders of magnitude more complex than the EQU function, and I produced them through a really dumb hit-and-miss algorithm which is obviously much less powerful than the Darwinian one. Frankly I am rather underwhelmed by their exercise.

    RBH wrote: ” Your example of producing the hash functions is akin to artificial selection, horticulture. Plant a large field of seeds and selection the variants you want. So the answer is that you did not “design” them, for all reasonable semantic values of “design.”I wonder about that. First of all horticulture works through stepwise refinement, so I think it’s more akin with Darwinism than with my one generation hit-and-miss algorithm. Secondly, hit-and-miss is a component of many a real world design process. Thirdly I think it is quite probable that in the future most technical design we humans will perform will be mostly (or perhaps completely) automated; would it then be right to say that we will have stopped designing things? Does the concept of design entail that it must be done by hand as it were? Similarly, would it be reasonable to say that a computer does not really calculate sums because it does not perform them long hand? Or that it does not play chess because it does not really understand the game?

    Anyway, the above is a semantic issue. What is clear is that these hash functions were created by me through my work and the application of my intelligence, and in order to fulfill a particular purpose of mine. And here’s a thought: Should a naturalist encounter these functions and discover that they came about through mechanistic means the naturalist would then probably claim that this evidences that I don’t exist, or at least that I am not necessary ;-)

    RBH wrote: ” Well, I myself don’t take it as a claim that it can be explained by mechanical processes. Rather, I take it as a working hypothesis or working assumption made so I can do science.”Agreed. Science is about discovering the mathematical order present in physical phenomena, and for doing science one must of course assume that this order exists.

    RBH wrote: ” And there’s some pretty powerful warrant for making that working assumption, namely three centuries of success in explaining, understanding, predicting, and controlling physical processes in the world, as contrasted with multiple millenia of failure on the supernaturalists’ part.”Sure, trying to understand, predict and control physical processes based on supernatural knowledge was and is an error. I wonder if you’d agree that the opposite error is also made in the case of scientism: to try to apply scientific knowledge on a non-scientific realm as is the human condition which is subjective, qualitative, and not objectively observable.

    To my observation that “The naturalist sees the deep order in the physical phenomena we observe and thinks that this demonstrates the non-existence of God.” RBH answered: “ No, this naturalist thinks that it demonstrates the non-necessity of God.

    Granted, because assuming God’s existence is indeed (and obviously) not necessary for discovering mathematical order in physical phenomena. Nor is it, by the way, for discovering abstract mathematical truths. After all there is a lot of marvelous and deep order within something as simple as the set of natural numbers. But then again, why should the assumption that God exists be required in these fields? You need not assume that God exists for playing chess either.

    The theistic thesis is that the existence of God is necessary for explaining *us* – the whole of our experience of life. And this is a completely different question. Religion submits that there a deep order here too, an order that transcends mere mathematical or mechanistic patters. It is an order and indeed harmony present in the quality of our experience of life, and in what we actually value in life. Indeed there is a quality and beauty in our discovery of mathematical or scientific truths, which itself coheres with this deeper order. And theism moreover submits that the best explanation for this deeper and overarching order is the presence of a person of utter perfection and who has created it. It should be obvious that when liberated from superstition religion cannot in any way come into conflict with science but rather transcends it. For science looks for a particular kind of order within a particular and sharply limited dimension of the human experience, whereas religion looks for order (and hence knowledge) in the whole of it.


CLOSE | X

HIDE | X