Mark Ludwig: Intelligent Design Theorist - Fact or Fiction?by Mark Ludwig.
Received: 15 May 2006
Published and replies inserted by Gert Korthof: 10 June 2006.
(Please note my insertions are in red and all my page references are to page numbers as they appear on the pages in the pdf version of the book.
Additions after 10 June 2006 are only in the form of Notes).
I thank Dr. Korthof for the opportunity to respond to his critique of my book Computer Viruses, Artificial Life and Evolution. I was rather surprised that it took 13 years for a proponent of evolution to pick it up and address it. Since it has taken so long, though, you may imagine my thinking has developed somewhat in those years. As such, I will preface my remarks by saying that to the extent that anything I write here differs from what is written in my book, it is due to a development of the ideas involved in the intervening time.
In contrast, the beauty of Artifical Life is that the philosophical and religious issues which have been stumbling blocks for a century and a half largely disappear. There we can study ideas like creation and evolution in a philosophically neutral environment. And the subject is fascinating in that context. I believe it also leads us to the essence of science in the purest sense - a place where we can come to some kind of understanding of how the world works - in a laboratory setting - without being stymied by religious differences. It is this very neutral ground that has made several centuries of rapid technological progress possible, and it is this very neutral ground that is the only hope for us to get past religious differences in the present instance.
One of the major points of the book is also to suggest that there is an important practical reason to get over these religious differences and get on with the business of science.
This book has plenty in it to offend everyone. (Such is the
nature of trying to expand peoples' thinking and open up new territory.) It has
obviously offended a defender of evolutionary origins. Yet it has offended the
What I offered the reader in my book is not the well-beaten path, not the professional lecture to a room full of students, but an initial exploration of important and fascinating questions. I am not trying to defend some kind of doctrine or dogma. I am trying to find some ground from which we can understand objective scientific truth in an often muddled world that is hypercharged with philosophical bias. I admit that is not easy, and perhaps I have not always succeeded, but I hope I have at least provided a rough map of this new territory that would be useful to the next explorer.
Misrepresentation of my goals, assertions and findings
There are a number of points in Dr. Korthof's article where he
misrepresents my thoughts by taking statements out of context.
Apparently he is doing this to support his assertion that I am an Intelligent Design Theorist - a
label which did not exist when I wrote my book.
1. Dr. Korthof is quick to point out that I discussed a fitness function that is unfriendly to evolution on page 215 of my book. He says "It is easy to construct a hypothetical Fitness Function unfriendly to evolution as Ludwig did. . . . Ludwig's figure (page 215) is just an imaginary illustration. It is not based on data. No conclusions about Darwinian selection can be based on that." Dr. Korthof does not point out that in the same breath I said "We have no reason to believe the fitness function does not look like a rising mountain range, with some populations at the peaks, and some on the slopes." (p. 215, CVALE) - the very thing needed to make Darwinian evolution work like a well-oiled machine.
Dr. Korthof says "to construct a realistic fitness landscape one needs a lot of data" and I agree, writing that "right now, it's hard to say what we can learn about the limitations of real-world evolution from these ideas." (p. 215)
Anyone who reads the book will see that I am not here proposing that the real world has a fitness function unfriendly to evolution. I am merely introducing the reader to the concept of a fitness function as a quantification of the Darwinian idea of "survival of the fittest". This fitness function allows one to mathematically represent fitness in some sense, which is obviously a precursor to any kind of a theory that can produce numbers.
2. Dr. Korthof is quick to point out that I cite authors like Philip Johnson who voices objections to evolution. He says "introducing and recommending Philip Johnson is introducing religious bias into his investigation. This is not the same as making his whole book worthless, but it is the opposite of what he wanted to do." He fails to note that I do not use Philip Johnson as a scientific resource. My book covers a lot of ground, from philosophy and history to science and computer programming. I clearly discuss Johnson's biases and his critics (p. 149, CVALE). His contribution, in my thinking, is primarily philosophical and clearly antagonistic. I propose not to blindly agree with him, but to use him: "This is a good way to find out how much we really know: subject your ideas to the harshest criticism and see what's left." (p. 231, CVALE). I also propose a solution to the heart of Johnson's criticism (p. 153, CVALE). For Dr. Korthof to castigate me for discussing Johnson in this context is like taking his own citation of Johnson in his review of my book as "proof that Dr. Korthof is a creationist in hiding".
3. Dr. Korthof says "Ludwig's list of 'Selected References' is extremely one-sided. That is easy to establish. Nearly all his references are critical of evolution or Darwinism. Did Ludwig compensate for this bias in any way?" He fails to mention that in my list of references are such staunch defenders of evolution as Richard Dawkins and Stephen Jay Gould, Nobel Laureate Francis Crick, as well as others who are wrestling with big questions from a totally non-religious viewpoint, such as Cairns-Smith and Fred Hoyle. Neither does he note that I cite genetics textbooks, books on Artificial Life, philosophy, and the philosophy of science.
I also defend the fact that I cited people like Johnson and Denton because anytime anyone wants to discuss the big questions, one runs up against philosophical / religious issues. Rather than trying to pretend those issues don't exist or that they have been finally resolved one way or another (when major segments of the population, many scientists included, beg to differ) I think it is best to look at them squarely. I don't know how to do that without drawing their arguments into the discussion.
4. Dr. Korthof says I ignore important subjects such as population genetics: "Ludwig completely misses the theory of population genetics." In fact I present quite a few important observations and discuss the outcome of experiments in population genetics - experiments which the reader is invited to perform in his or her own computer. (pp. 197-223) My great fault is apparently that I present this subject in the context of Artificial Life. Since Dr. Korthof denies the essential simplification which is common to Artificial Life and biological life, this makes my population genetics irrelevant in his opinion. (More on this below.) Understand, however, that such an opinion is becoming more and more of an arcane curiosity with time. Biologists are doing more and more genetics inside of computers, and people are winning Nobel prizes for that work, while programmers are making great strides in using genetic algorithms to solve complex real-world problems.
5. In a number of instances Dr. Korthof cites advertising copy for my book on the internet as if it were quotations out of my book. Needless to say, citing advertising copy as representative of an author's viewpoint is somewhat less than professional in scientific circles. To cite it in a way that could possibly confuse the reader into thinking it is a quote from the book is disingenuous. Dr. Korthof's method of quoting the ad copy and only indicating that it is ad copy with a footnote is really the limit . . . and he doesn't always do that. For example, when he says "I do think that it substantially contributed to the outrageous claim that 'evolutionary biology is in an abysmal state'" he is not quoting Computer Viruses Artificial Life and Evolution, but ad copy.
6. Dr. Korthof states that "Ludwig's goal was an unbiased, unprejudiced assessment of the theory of biological evolution." Where he got that idea, I don't know. I stated that my goal was to explore some new territory that had never been explored before, and confessed that "I'm not writing this book because I have all the answers. Quite to the contrary, I have lots more questions than answers!" (p. 5, CVALE) Dr. Korthof should also note that I said plainly "my purpose isn't to debunk evolution here, or to argue against it" (p. 241, CVALE). More on my real purpose below....
7. Dr. Korthof says "the first half of the book is based on the idea that viruses and artificial life are nothing but instructions to be executed (by a computer). Ludwig translates this view to biological systems." Yet he contradictorily states "most of his book is based on the assumption that viruses are alive." In fact I spend a major part of the book considering the philosophical, moral and scientific ramifications of suggesting that computer programs can be alive, and hoped the reader would understand that there is no easy answer.
8. Dr. Korthof states that I espouse the idea that "when one cannot calculate the evolution of bacterium to humans, the whole theory fails." He cites a reference, number 6, here, which the casual reader might think is a citation in my book. In fact, he is citing Philip Johnson. I didn't say that and I don't believe it.
Dr. Korthof's misrepresentations all lean in the direction of supporting his central thesis: the exposure of another Intelligent Design Creationist. In all fairness, I understand that Dr. Korthof is involved in the heat of the battle between creation and evolution, and to some extent I can excuse him for these misunderstandings. I hope they are not intentional. Yet what do those misunderstandings buy in the end? At best, it seems they short circuit people's brains so that they won't consider some of the most fascinating questions in the world any further.
Okay, let's go on now to the major issues . . . .
Are the results of AL applicable to the real world?
A major part of Dr. Korthof's critique seems to focus on emergence. He writes "How did he establish that his results are relevant for biological evolution? Surprisingly, he did not really attempt to answer that question . . . . Remarkably, Ludwig knows that biological objects are too complex and computer viruses and AL are too easy to study . . . ." This "too complex/too easy" issue seems, in Dr. Korthof's mind, to revolve around the idea of emergence. He appears to assert that biological life is fundamentally unpredictable, and thus none of the results of Artifical Life can have any bearing on biology.
Such an assertion seems rather surprising coming from a
professional biologist, in as much as it could be understood as a virtual
rejection of the whole purpose and program of science itself. It is like saying
that Newtownian mechanics is irrelevant to our world because, well, the world is
just too complicated to be understood.
The idea of "emergence" comes from the Artifical Life community's attempts to model life. At the time of my writing (1992 time frame) AL pioneers were exploring various criteria whereby one could say that something is alive, and "emergence" was one such criterion. "Emergence" can be stated as the property that "the behavior of an organism as a whole exhibits behavior which could not be deduced from the behavior of the individual parts." (p. 35, CVALE) Living organisms, it was proposed, should exhibit some form of emergent behavior.
In Computer Viruses, Artificial Life and Evolution I attempted to make a distinction by differentiating between "strong" and "weak" emergence. Weakly emergent behavior I defined as an emergence that is only apparent, due to our lack of understanding of a system under consideration. Strongly emergent behavior, I defined as a phenomenon where something really new that cannot in any way be predicted, results. (pp. 85, 86, CVALE) I believe this is an important distinction, and very relevant to our discussion. It is somewhat like the questions and issues which arise out of the irreducible uncertainty in quantum theory. One cannot pin down such uncertainties by making more accurate measurements - they are inherent in the basic physics itself.
The whole discipline of science essentially consists of studying unexplained phenomena and finding explanations for them. That study can go in two basic directions: (a) explanation in terms of existing laws, and (b) the discovery of new laws. My idea of strongly emergent behavior is simply the idea that new laws of nature must be invoked - track (b). In contrast, weakly emergent behavior implies the success of track (a), the explanation of a new phenomenon in terms of old laws.
An example of weak emergence is, for example, the emergence of Newtonian mechanics from quantum mechanics. It can be demonstrated that quantum mechanics predicts Newtonian mechanics in the appropriate limits. An area of potentially strong emergent behavior might be the emergence of mind, and the laws of psychology, from neurology.
Any assertion of strong emergence must be made cautiously. Really, the burden of proof should lie on anyone making such an assertion. Men have a way of grossly underestimating the power of science to understand things, and the history of science is littered with the remains of supposedly strongly emergent behaviors that have been thoroughly explained by the laws of their component parts.
Dr. Korthof appears to be an advocate of the idea that wet biological organisms are strongly emergent, whereas computer programs are not and cannot be. This is a surprising and unusual position for an advocate of evolution. I did not take such a strong position in my book. As I wrote, "My feeling is that emergent behavior is real, at least in nature, but I must say that timidly." (p. 71)
Dr. Korthof also asserts that, because life is strongly emergent and AL cannot be, my work is irrelevant to biology:
However, this "dilemma" is the very process of simplification - the elimination of irrelevant variables - that is the essence of science! If Dr. Korthof wishes to chide me for simplification just because it is simplification, then he is acting like an astrologer chiding a psychologist for failing to take planetary positions into account in his research. If he wishes to question the validity of that simplification, it is another matter. I hope the latter is the case, although his heavy reliance on trying to discredit my work merely on the basis of simplification tends to suggest the former.
I would say that the burden of proof in asserting that the simplification is invalid is definitely on Dr. Korthof though. The very fact of the existence of a science of genetics is strong evidence that the simplification made by AL is indeed valid. If I were mischevious I could turn Dr. Korthof's arguments a bit to assert that genetics is "no substitute for studying the messy, wet and dirty thing called 'life'", to use his own words.
Let me explain this a bit, and hopefully indicate why this simplification is so possible: A computer program is only much simpler than a living organism at a certain level of analysis. If I compare a computer program at the level of the logic of the programming language to the molecules flying about in every direction in a living cell, then the program looks simple indeed. However, if I analyze the electronic states in a maze of semiconductor and ferromagnetic materials, it is questionable whether wet life would still be considered more complex.
In the case of a commercial computer, I don't have to worry about individual atoms and semiconductors because the parts of the computer have been designed to elimiate the need to consider them. This permits tremendous simplification when determining exactly what a program will do, and because this simplification is possible, computer science is possible.
The fact that a science of genetics is possible is a direct
result of a similar simplification that is possible in wet biology. Dr. Korthof
does not sem to get this.
Computer code works in exactly the same way. Apart from a knowledge of the hardware, the CPU and its instruction set, one cannot tell what a sequence of bits recorded in the magnetic domains of a hard disk will do. They could be a computer program for a Pentium or a Shakespeare play. Or they could be instructions for a 23rd century desktop DNA sequencing machine to code the DNA for the brunette.
Neither is this simplification a logical necessity for either biology or computers. At the frontiers of computer research, scientists try to nail down ways of making the simplification possible in a world where quantum uncertainties loom large. In biology, one might imagine a world in which the simplification is not possible. For example, those who study pre-biological chemistry often deal with such situations. Certainly we may understand that the simplification was non-trivial by the fact that men have won Nobel Prizes for figuring it out. There is something very important and fundamental here. Both the fact of our existence as a species, and the economic foundations of the modern world depend on this very simplification.
In any event, it is this simplification, this separation between code and interpreter, that makes both genetics and computer science possible, and which establishes a logical connection between the two, whereby results in one field have a bearing on results in the other. It is for this reason that computer scientists can abstract properties of life and build efficient evolutionary programs and more life-like animations. It is for this reason that geneticists can use computers to solve genetics problems that might not otherwise be tractable. There are no paradoxes or dilemmas here. Results in AL are relevant to life. The burden of proof really rests on those who would assert otherwise, and Dr. Korthof fails to make his case.
Of course, one must recognize that AL is perhaps best understood as a superset of real life. With the power to create worlds with their own intermediate rules inside a computer, we can not only model life, we can create worlds that have no analogy in the real world, and perhaps have no bearing on real-world biology. In my book I attempted to stand back and take a broad view of this horizon, realizing that some of the worlds I might create will support Artificial Life and some will not. Some of the worlds that support AL may support very little variety, and some may support a tremendous variety. Of those which support variety, some may support evolution and some may not.
Within the superset, Dr. Korthof's assertion that biological
life is more complex than AL would also seem to break down. I do not know of any
professional biologists who believe that, given enough computing power and
enough time to figure everything out, they will not be able to accurately model
simple life forms inside a computer. At that point, we might say that at least
some biological life has been brought within this superset. Dr. Korthof is
strangely evasive in explaining just why he thinks this cannot happen.
Thus Dr. Korthof's assertion that the results of AL have no value to research in wet biology is lacking in substance. Artificial Life is totally relevant to biology.
Where Viruses and Wet Life Really Differ
Because Dr. Korthof misunderstood the purpose of my book, he misunderstood my focus, and why I do not folow the normal path which evolutionary biologists follow. Although biology and Artificial Life have much in common, the primary questions which biologists have historically been interested in, and the questions which AL researchers are interested in, are remarkably different. Historically speaking, much of evolutionary biology's efforts have been explanatory of what exists, and backward-looking.
As a computer virus researcher, I think that one of the most significant events in history could be the invention of computer viruses. To me it is like witnessing a second creation, in which we are the gods . . . and yet we are gods that might be supplanted and spurned by our own creations. Consider the possibility that evolution really is every bit as powerful as Darwin suggested, that, from a little bit of DNA, RNA and proteins, our wonderful, complicated world really did evolve. If that is the case, then it is more than conceivable that a similar thing could happen in the world of bits and bytes. Not only could it happen, it could happen millions or billions of times faster in this digital world than it did in the real world, simply because things can work a whole lot faster inside of computers than they can in the soupy chemistry of earth.
It is easy to pooh-pooh such ideas, counting them to be mere science fiction. However, the whole idea of computer viruses was science fiction in the 1970s, quite literally. Really, it is amazing to consider that we engineered an environment which could harbor a totally alien form of life without our even realizing what we had done . . . until that life form started crawling around in our computers, much to our consternation. And not only did we create an environment that could harbor life, but (as I demonstrated in my book) this environment could harbor evolving life forms. This environment was not at all designed to harbor life. Quite to the contrary, it has not been wanted. Yet the "life" is apparently there and able to thrive.
Evolutionary biologists seem to be fairly certain that life can, does and will continue to evolve in the direction of increasing complexity. Genetic programming has demonstrated that evolution can be used to speedily solve complex computing problems. If we simply take these observations and apply them naively to the world of computer viruses, we come to a rather startling conclusion: Under the right conditions computer viruses could begin to evolve in an explosive spiral of ever-increasing complexity. The pre-conditions for this possibility to materialize seem to be in place. Add to this the fact that one can mathematically prove that it is impossible to write a perfect virus scanner. That means scanners can never be used to put an end to this explosive spiral - they can only drive it and make it worse. Then place these facts in the context of the modern world, in which both governments and non-governmental organizations are spending big money to develop malevolent software, including computer viruses, for both military purposes and terrorism.
In view of these considerations, I believe the possibility now exists that one day (perhaps not too very far away) the right conditions might be fulfilled - perhaps quite by accident - to initiate an evolutionary explosion. Already sophisticated and extremely malevolent software could undergo a rapid and (at present) entirely unpredictable development in which the only goal is to survive mankind's attempts to eradicate it. It is not inconceivable that this explosion could take place in a matter of hours or days, and be far beyond the capability of all of mankind to arrest it.
As far as I can see, there is no generally accepted scientific principle by which we can conclude that such a scenario cannot happen. Quite to the contrary, the science we know today rather indicates that it is likely to happen.
Here we have the essential difference between biological life
and computer viruses. The big questions which biologists have traditionally been
interested in are historical. Thus, they spend time studying the fossil record,
studying the genetic record for evidence of common descent, etc.
All of this is not to say that biologists never look forward and computer virus researchers never look back. For example, a biologist might try to figure out how to remove a bad gene from the gene pool. A computer virus researcher might do forensics to determine where some computer virus came from.
Much of the focus of my book is on this forward-looking
science. Dr. Korthof apparently did not understand this. Thus, he berates me as
having "missed the argument for common descent" etc., concluding that I am
"without sufficient training in biology". In reality, the argument for common
descent is irrelevant to this forward-looking science. And although Dr. Korthof
has to rely on advertising literature to impose on me the conclusion that I
think "evolutionary biology is in an abysman state",
So Will Viruses Take Over the World??
Suppose that over the course of time computer viruses and
operating systems become complex enough that Darwinian evolution kicks in and
begins to create new and increasingly complex viruses ad infinitum. I can learn
nothing from evolutionary biologists to indicate that this can't or won't
Obviously, if there is a potential that computer viruses or some other kind of living program could take over the world at some point in the future, it would be good to know about it beforehand, and to have some idea of the dynamics of how that could happen. With such knowledge, we might be able to avert a potential catastrophe. Most people don't think about such things too much because they naively leave their computer security in the hands of antivirus software vendors. They fail to realize that when evolution kicks in those vendors could be overwhelmed, and unable to cope with even 0.01% of the new species of viruses that could evolve.
There are basically two ways in which we might be able to conclude that this catastrophe is not inevitable, and learn ways to deal with it. The hypothesis of this digital armageddon rests on two postulates: (1) There is no fundamental difference between computer viruses and living organisms that makes one able to evolve in a large-scale fashion and the other not, and (2) Evolution is capable of driving an ever increasing spiral of complexity within time frames that make it impossible for us to understand what it produces and overcome it.
If one of these two postulates is wrong, the hypothesis could likewise fail.
Dr. Korthof appeared to take issue with postulate #1, asserting that viruses are too simple and biological life is too complex. I have dealt with this above. At bottom, computer viruses are essentially like living organisms. They are self-reproducing and they carry genetic code in their program. That is the essential point. Anything else is really irrelevant. To argue, for example, that computer viruses are really more like biological viruses, as Dr. Korthof argued is both wrong and irrelevant. (Since computer viruses do not attack self-reproducing programs, they are not like biological viruses.)
In Computer Viruses, Artificial Life and Evolution I look at both possibilities concerning postulate #1. I look at computer viruses and life and compare them. While recognizing that there could be something different about viruses and biological life, this difference is perhaps more metaphysical than scientific. Dr. Korthof catches a glimpse of this in his assertions about life being too complex and viruses too simple, but he will end up being driven to some kind of mysticism to keep life "too complex" in the face of advancing scientific knowledge.
The other alternative is to take a second look at evolution. Most creationists take issue with postulate #2, asserting that evolution was not powerful enough to create all of the variety of life in our world, and therefore would not be powerful enough to cause viruses to evolve except in very minor ways. That is a comforting possibility, but the human race cannot really afford to entrust its future to such a blind dismissal.
Understand that 100% of the computer security specialists who deal with computer viruses are die-hard creationists in this sense. They believe that every computer virus they come across or ever will come across must have been created by some (human) intelligence. These men have the full trust and confidence of every computer user, every business, every government on the face of the earth. These specialists do not realize the incredible commitment they have made to creationism, and what they are willing to risk for that commitment. Most professional biologists are utterly blind to the existence of this community of creationists, and even take their side, as Dr. Korthof has.
In Computer Viruses, Artificial Life and Evolution, I again look at both possibilities concerning postulate #2. I consider the creationist's arguments that evolution is impotent. I consider the possibility that it isn't. In the end, I have to conclude that the good hard science - the kind that uses equations and provides solid predictions - just doesn't exist to answer this question. Given the fact that this question - Could evolution kick in in the world of computer viruses? - appears awfully important to our future economic and intellectual development, I think it is absolutely foolish to sit around and wait to find out what the answer is experimentally. Yet that is what is happening today.
The evolutionary biologists and the Artificial Life researchers are the closest of anyone to having the answers to deal with this problem. However no one will take them seriously if they just apply their general beliefs about large-scale evolution in our world to computers, because those beliefs essentially say the cataclysm is inevitable. The creationists' position is a lot more comfortable in this case, and I believe many people have adopted it for this reason (often, perhaps, encouraged by their religious biases).