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Denton - an evolutionary critic changes his tune - big time!
A little long I know...bolds are mine BTW. I even had to chop it a bit to fit BTW...
Nature's Destiny.
From the impossibility of evolution to the inevitability of evolution: Anti-Evolutionst Michael Denton turns into an 'Evolutionist'.
A review by Gert Korthof
23 May 2000
'Nature's Destiny' is one long argument for the biocentric Fine Tuning of the Universe. In that sense it is a greatly expanded version of the chapter "The Puzzle of Perfection" in his Evolution: a theory in crisis(1986). However the Fine Tuning Argument does not only imply cosmological evolution, but it also implies biological evolution. And that is exactly what his previous book Evolution: A Theory in crisis attacked in the most thorough way. And biological evolution, that is the common descent of all life, is exactly what he defends now in Nature's Destiny. Not a limited version of evolution. No, complete naturalistic evolution from inorganic materials to the first cell to humans.
Thereby he directly opposes 'special creationists' such as Phillip Johnson (6). Above that he claims that evolution is directed and the origin of life is inevitable if conditions are right.Does he present new facts about evolution to support his claim ? Do we learn from his new book what exactly was wrong with the anti-evolution arguments in his previous book?
In my review of The Anthropic Cosmological Principle, I wondered why anti-evolutionists like Johnson, Denton(1986) and Behe never exploited the Fine Tuning argument to prove the existence of a designer. If they knew about the Fine Tuning at all, then the reason must be that fine tuning involves evolution and evolution involves randomness. And this was seen as contradictory to a purposeful universe by the creationists. Therefore they were unable to utilize the Fine Tuning Argument. Paradoxically, an argument for the Design of the Universe wasn't available to creationists!
Denton is the first anti-evolutionist and anti-Darwinist I know who uses the FT argument to prove design of the universe. He gave up his opposition to evolution. This is nothing less than going from the impossibility of biological evolution to the inevitability of evolution ! How could he do so ? For he had not only shown in his Evolution: A Theory in crisis, that the Darwinian mechanism for evolution could impossibly do what it was supposed to do, but also that all the biological facts pointed to his anti-evolutionary Typological Model, which denied the reality of (macro-)evolution. According to Denton(1986) there were no intermediates; there were gaps in the fossil record; protein sequence data prove discontinuity; in the end Darwinists failed to provide evidence for macro-evolution; failed to establish the fact of evolution and failed to provide an adequate mechanism capable of transforming species on a macro-scale. However Denton did accept a limited form of evolution : micro-evolution. So in Nature's Destiny he had to overcome two of his own obstacles: the mechanism and the fact of evolution. Did he succeed and how ?
First: the fact of evolution. In Nature's Destiny Denton does not address the issue directly, so it is difficult to point to one or two facts which made the difference. Remarkably, he refers to Kaufmann(1) and deDuve(2), to show that, given the right initial conditions, the origin of life and evolution is inevitable.
Second: the mechanism of evolution. Denton is clearer about that. Denton presents 'new' evidence for the adequacy of the Darwinian mechanism of evolution (surprise!) and he tries to escape the randomness of the Darwinian evolutionary process by postulating 'directed evolution' (surprise!). This remarkable paradigm change of Denton, necessitates exclusive attention to Evolution in part I of my review. In part II of my review I discuss the biocentric cosmos thesis.
What is his goal ? The aim of Nature's Destiny is first, to present the scientific evidence for believing that the cosmos is uniquely fit for life as it exists on earth and for organisms of design and biology very similar to our own species, Homo sapiens, and second that this is entirely consistent with the older teleological religious anthropocentric view of the cosmos.
Why does Fine Tuning imply biological evolution?
Life did not exist at the beginning of the universe. The 'purpose' of the fine tuning is to 'ensure' the production of life by fine tuning the initial conditions of the universe.
What is his 'new' evidence for evolution ?
Can we find crucial evidence in his book which converted him to evolution ? The key passage, I think, occurs in the paragraph "The Closeness of All Life in DNA Sequence Space" of CH 12 (p276). It must have been the key insight for Denton. It reads:
"One of the most surprising discoveries which has arisen from DNA sequencing has been the remarkable finding that the genomes of all organisms are clustered very close together in a tiny region of DNA sequence space forming a tree of related sequences that can all be interconverted via a series of tiny incremental natural steps".[emphasis is mine]
I wished Denton showed evidence for this (9). It is neo-Darwinism in a nutshell, it is what neo-Darwinists assumed all the time! He continues:
"So the sharp discontinuities, referred to above, between different organs and adaptations and different types of organisms, which have been the bedrock of antievolutionary arguments for the past century (3), have now greatly diminished at the DNA level. Organisms which seem very different at a morphological level can be very close together at the DNA level." [emphasis & note are mine]
So his main obstacle to believing in a step-by-step change of organisms has been blown to pieces. That's why he now can accept evolution. And the special character of the DNA evidence is, I think, that it unites evidence for the fact of evolution (DNA looks like a tree of sequences) and evidence for the mechanism of evolution (DNA is subject to small mutations). DNA-evidence is the fact and the mechanism of evolution.
Is this the whole story? No. DNA has the potential to overcome the obstacle of functionless intermediates by 'going underground': simply not being translated into proteins. Then it can mutate in any direction without being harmful to the organism. In Denton's words:
"Thus, new organs and structures that cannot be reached via a series of functional morphological intermediates can still be reached by change in DNA sequence space." (p279)
Taken together with the previous argument, the whole argument eliminates Denton's 'last' obstacle to evolution and so there is 'nothing' with prevents him anymore from acceptance of the fact and mechanism of biological evolution. He could have known in 1986 the theoretical possibility of DNA's capacity, but was blinded by selfconstructed discontinuities in enzymes like Cytochrome-C. Now Denton has the facts that support this theoretical possibility: a divers group of cichlids differ only 0.4% in their DNA, human and chimpanzee differ only 1% in their DNA, etc.
Is this the whole story? Again: NO. This is because the Fine Tuning argument implies teleology, that is a goal, a purpose, a direction. The universe is fine tuned for something and that something is life and humans. This is not really compatible with the Darwinian trial and error process! So Denton's acceptance of evolution would be for nothing ? He still finds the obstacle called 'randomness' on his road to the purposeful universe. What is Denton's solution? His answer is: 'directed evolution'.
What is the evidence for 'directed evolution' ?
Let us state the problem again: the outcome of a trial and error process is unpredictable. The existence of humans could be a lucky accident. Natural selection is undirected according to neo-Darwinism. The possibility of letting some designer do some tampering during the evolutionary process is blocked by Denton's rejection of any supernatural intervention (see quote from page xviii). So where does the direction come from ? There isn't a chapter devoted to 'directed evolution', in stead of that one learns about 'directed evolution' in Ch 15, where he, remarkable enough, again challenges neo-Darwinian evolution with new examples like the unique eye of the lobster and old ones like the avian lung ! However, the most remarkable change is, when we compare it to Denton(1986), that the challenge is now for the mechanism of evolution, not for the fact of evolution. Let us have a look at Denton's new logic:
"Again, as in the two cases cited above, it is hard to believe that any sort of unguided evolutionary mechanism would have realized such an unusual adaptive end." (p360). [emphasis is mine]
"Just how such a different respiratory system could have evolved gradually from the standard vertebrate design without some sort of direction is, again, very difficult to envisage..." (p 361) [emphasis is mine].
What was a challenge to evolution and Darwinism in 1986 is now evidence for directed evolution against a background of inevitable evolution. Denton does not account for this paradigm change. It is clear from these quotes alone that Denton's 'evidence' for directed evolution is negative. Some adaptations cannot be explained by the random Darwinian mechanism, so they must be somehow 'directed'. A footnote is revealing where 'direction' is coming from :
"We can envisage such a contriving or tampering of the DNA space to be analogous to rearranging the structure of the English lexicon to permit the evolution of a particular word tree, ... However, by playing God and restructuring the lexicon we would be able to arrange a vast word tree within the letter space, so that all functional words were clustered together..." [emphasis is mine] (page 434). (4)
By DNA space he means the set of all possible DNA sequences. My criticism is that if restructuring the lexicon is analogous to restructuring the DNA space, than this boils down to intervention and Denton excludes intervention from the beginning of his book. Why does this imply intervention ? Because one cannot fine tune the 4 DNA-bases A,T,C,G so that the DNA-sequences are restricted to easily interconvertible useful DNA-sequences. And this is so because the 4 bases do not and cannot restrict DNA sequences in any way. Why ? Because there is nothing in the 4 bases that enforces a sequence ATACGATCGA rather than CTACGTTACC. Or any other sequence. And this is necessarily the case. Otherwise DNA would not be fit for the task of information storage. Each of the 4 bases can be linked to each of the 4 bases. Every DNA sequence can be produced with the 4 bases (8). There is no restriction in length and composition, which derives from the 4 bases. The information content of DNA is irreducible to the properties of the 4 bases. Just as a book is not reducible to the properties of the alphabet. In my view evolution is essentially an open ended adventure. Contrary to Denton I believe a trajectory through DNA space itself cannot be pre-programmed. See also his paragraph "Constraints in Sequence Space" (p281), where he makes very clear that he believes in a "prearranged DNA sequence space". No, constraints must be found outside the DNA space. I do not object to constraints, but they cannot be a substitute for searching the DNA space. Denton's insistence on the tampering with the DNA space as the main mechanism of 'directed evolution' conflicts with his rejection of unnatural interventions. Denton assumes manifold occurrences of tampering in the history of the cosmos and life:
1) tampering with the physical constants
2) tampering with the chemical properties of C,N,O,H, etc.
3) tampering with the selection of the 4 most efficient bases to be included in DNA
4) tampering with the structure of DNA (and proteins)
5) tampering with the DNA space
The last action surely is intervention. The bottomline is this: either fine tuning of initial conditions is sufficient for a biocentric universe or one needs tampering during the evolutionary process, which is intervention, which conflicts with his naturalism. Conclusion: impossible to fine tune the 4 bases A,T,C,G to produce directed evolution! In my view there is only one conclusion open for Denton: the designer of the 'Intelligent Design Theorists' (8). And what can I say more about Denton's evidence for directed evolution, than what Denton says himself (on another page): "Of course, these discoveries do not prove directed evolution" (p292).
Is Denton a Darwinist ? Above we saw that Denton accepted that organisms are genetically linked (common descent). In that sense he is an evolutionist and a Darwinist. However, in so far Denton accepts directed evolution, and in so far he accepts that the course of evolution is preprogrammed, and in so far he accepts Sheldrake-forces (p365), and in so far he defends foresight in evolution (p362), he rejects neo-Darwinism.
Is this the whole story? I cannot tell the whole story, because Michael Denton does not tell the whole story. The whole story includes answers to questions like: What about The Enigma of Life's Origin ? What about The Typological Perception of Nature ? What about The Fossil Record ? What about The Failure of Homology ? What about The Biochemical Echo of Typology ? (these are chapters in Evolution: A Theory in Crisis) (5). Since Denton does not tell us about it, the only thing I can do is read between the lines. In the 'Note to the Reader' Denton makes an important and revealing remark:
"Because the validity of the argument [biocentric design of the universe] depends on so many independent lines of evidence, the conclusion is not materially threatened because the whole picture is not yet complete or because this or that phenomenon such as the origin of life or the mechanism of evolution is not understood. Just as the meaning of a jigsaw puzzle may be obvious long before all the pieces are perfectly placed, so too my argument does not necessitate that everything be explained."
There is a second reason why problems with evolution do not have the impact they had in 1986 and that is the inevitability of life:
"that carbon-based life is therefore inevitable on any planetary surface where conditions permit it."(p265)
It should be clear that once the inevitability of the origin and evolution of life is accepted, all problems we have in understanding how it all happened, are not falsifications, but a sign of our own ignorance.
A little long I know...bolds are mine BTW. I even had to chop it a bit to fit BTW...
Nature's Destiny.
From the impossibility of evolution to the inevitability of evolution: Anti-Evolutionst Michael Denton turns into an 'Evolutionist'.
A review by Gert Korthof
23 May 2000
'Nature's Destiny' is one long argument for the biocentric Fine Tuning of the Universe. In that sense it is a greatly expanded version of the chapter "The Puzzle of Perfection" in his Evolution: a theory in crisis(1986). However the Fine Tuning Argument does not only imply cosmological evolution, but it also implies biological evolution. And that is exactly what his previous book Evolution: A Theory in crisis attacked in the most thorough way. And biological evolution, that is the common descent of all life, is exactly what he defends now in Nature's Destiny. Not a limited version of evolution. No, complete naturalistic evolution from inorganic materials to the first cell to humans.
Thereby he directly opposes 'special creationists' such as Phillip Johnson (6). Above that he claims that evolution is directed and the origin of life is inevitable if conditions are right.Does he present new facts about evolution to support his claim ? Do we learn from his new book what exactly was wrong with the anti-evolution arguments in his previous book?
In my review of The Anthropic Cosmological Principle, I wondered why anti-evolutionists like Johnson, Denton(1986) and Behe never exploited the Fine Tuning argument to prove the existence of a designer. If they knew about the Fine Tuning at all, then the reason must be that fine tuning involves evolution and evolution involves randomness. And this was seen as contradictory to a purposeful universe by the creationists. Therefore they were unable to utilize the Fine Tuning Argument. Paradoxically, an argument for the Design of the Universe wasn't available to creationists!
Denton is the first anti-evolutionist and anti-Darwinist I know who uses the FT argument to prove design of the universe. He gave up his opposition to evolution. This is nothing less than going from the impossibility of biological evolution to the inevitability of evolution ! How could he do so ? For he had not only shown in his Evolution: A Theory in crisis, that the Darwinian mechanism for evolution could impossibly do what it was supposed to do, but also that all the biological facts pointed to his anti-evolutionary Typological Model, which denied the reality of (macro-)evolution. According to Denton(1986) there were no intermediates; there were gaps in the fossil record; protein sequence data prove discontinuity; in the end Darwinists failed to provide evidence for macro-evolution; failed to establish the fact of evolution and failed to provide an adequate mechanism capable of transforming species on a macro-scale. However Denton did accept a limited form of evolution : micro-evolution. So in Nature's Destiny he had to overcome two of his own obstacles: the mechanism and the fact of evolution. Did he succeed and how ?
First: the fact of evolution. In Nature's Destiny Denton does not address the issue directly, so it is difficult to point to one or two facts which made the difference. Remarkably, he refers to Kaufmann(1) and deDuve(2), to show that, given the right initial conditions, the origin of life and evolution is inevitable.
Second: the mechanism of evolution. Denton is clearer about that. Denton presents 'new' evidence for the adequacy of the Darwinian mechanism of evolution (surprise!) and he tries to escape the randomness of the Darwinian evolutionary process by postulating 'directed evolution' (surprise!). This remarkable paradigm change of Denton, necessitates exclusive attention to Evolution in part I of my review. In part II of my review I discuss the biocentric cosmos thesis.
What is his goal ? The aim of Nature's Destiny is first, to present the scientific evidence for believing that the cosmos is uniquely fit for life as it exists on earth and for organisms of design and biology very similar to our own species, Homo sapiens, and second that this is entirely consistent with the older teleological religious anthropocentric view of the cosmos.
Why does Fine Tuning imply biological evolution?
Life did not exist at the beginning of the universe. The 'purpose' of the fine tuning is to 'ensure' the production of life by fine tuning the initial conditions of the universe.
What is his 'new' evidence for evolution ?
Can we find crucial evidence in his book which converted him to evolution ? The key passage, I think, occurs in the paragraph "The Closeness of All Life in DNA Sequence Space" of CH 12 (p276). It must have been the key insight for Denton. It reads:
"One of the most surprising discoveries which has arisen from DNA sequencing has been the remarkable finding that the genomes of all organisms are clustered very close together in a tiny region of DNA sequence space forming a tree of related sequences that can all be interconverted via a series of tiny incremental natural steps".[emphasis is mine]
I wished Denton showed evidence for this (9). It is neo-Darwinism in a nutshell, it is what neo-Darwinists assumed all the time! He continues:
"So the sharp discontinuities, referred to above, between different organs and adaptations and different types of organisms, which have been the bedrock of antievolutionary arguments for the past century (3), have now greatly diminished at the DNA level. Organisms which seem very different at a morphological level can be very close together at the DNA level." [emphasis & note are mine]
So his main obstacle to believing in a step-by-step change of organisms has been blown to pieces. That's why he now can accept evolution. And the special character of the DNA evidence is, I think, that it unites evidence for the fact of evolution (DNA looks like a tree of sequences) and evidence for the mechanism of evolution (DNA is subject to small mutations). DNA-evidence is the fact and the mechanism of evolution.
Is this the whole story? No. DNA has the potential to overcome the obstacle of functionless intermediates by 'going underground': simply not being translated into proteins. Then it can mutate in any direction without being harmful to the organism. In Denton's words:
"Thus, new organs and structures that cannot be reached via a series of functional morphological intermediates can still be reached by change in DNA sequence space." (p279)
Taken together with the previous argument, the whole argument eliminates Denton's 'last' obstacle to evolution and so there is 'nothing' with prevents him anymore from acceptance of the fact and mechanism of biological evolution. He could have known in 1986 the theoretical possibility of DNA's capacity, but was blinded by selfconstructed discontinuities in enzymes like Cytochrome-C. Now Denton has the facts that support this theoretical possibility: a divers group of cichlids differ only 0.4% in their DNA, human and chimpanzee differ only 1% in their DNA, etc.
Is this the whole story? Again: NO. This is because the Fine Tuning argument implies teleology, that is a goal, a purpose, a direction. The universe is fine tuned for something and that something is life and humans. This is not really compatible with the Darwinian trial and error process! So Denton's acceptance of evolution would be for nothing ? He still finds the obstacle called 'randomness' on his road to the purposeful universe. What is Denton's solution? His answer is: 'directed evolution'.
What is the evidence for 'directed evolution' ?
Let us state the problem again: the outcome of a trial and error process is unpredictable. The existence of humans could be a lucky accident. Natural selection is undirected according to neo-Darwinism. The possibility of letting some designer do some tampering during the evolutionary process is blocked by Denton's rejection of any supernatural intervention (see quote from page xviii). So where does the direction come from ? There isn't a chapter devoted to 'directed evolution', in stead of that one learns about 'directed evolution' in Ch 15, where he, remarkable enough, again challenges neo-Darwinian evolution with new examples like the unique eye of the lobster and old ones like the avian lung ! However, the most remarkable change is, when we compare it to Denton(1986), that the challenge is now for the mechanism of evolution, not for the fact of evolution. Let us have a look at Denton's new logic:
"Again, as in the two cases cited above, it is hard to believe that any sort of unguided evolutionary mechanism would have realized such an unusual adaptive end." (p360). [emphasis is mine]
"Just how such a different respiratory system could have evolved gradually from the standard vertebrate design without some sort of direction is, again, very difficult to envisage..." (p 361) [emphasis is mine].
What was a challenge to evolution and Darwinism in 1986 is now evidence for directed evolution against a background of inevitable evolution. Denton does not account for this paradigm change. It is clear from these quotes alone that Denton's 'evidence' for directed evolution is negative. Some adaptations cannot be explained by the random Darwinian mechanism, so they must be somehow 'directed'. A footnote is revealing where 'direction' is coming from :
"We can envisage such a contriving or tampering of the DNA space to be analogous to rearranging the structure of the English lexicon to permit the evolution of a particular word tree, ... However, by playing God and restructuring the lexicon we would be able to arrange a vast word tree within the letter space, so that all functional words were clustered together..." [emphasis is mine] (page 434). (4)
By DNA space he means the set of all possible DNA sequences. My criticism is that if restructuring the lexicon is analogous to restructuring the DNA space, than this boils down to intervention and Denton excludes intervention from the beginning of his book. Why does this imply intervention ? Because one cannot fine tune the 4 DNA-bases A,T,C,G so that the DNA-sequences are restricted to easily interconvertible useful DNA-sequences. And this is so because the 4 bases do not and cannot restrict DNA sequences in any way. Why ? Because there is nothing in the 4 bases that enforces a sequence ATACGATCGA rather than CTACGTTACC. Or any other sequence. And this is necessarily the case. Otherwise DNA would not be fit for the task of information storage. Each of the 4 bases can be linked to each of the 4 bases. Every DNA sequence can be produced with the 4 bases (8). There is no restriction in length and composition, which derives from the 4 bases. The information content of DNA is irreducible to the properties of the 4 bases. Just as a book is not reducible to the properties of the alphabet. In my view evolution is essentially an open ended adventure. Contrary to Denton I believe a trajectory through DNA space itself cannot be pre-programmed. See also his paragraph "Constraints in Sequence Space" (p281), where he makes very clear that he believes in a "prearranged DNA sequence space". No, constraints must be found outside the DNA space. I do not object to constraints, but they cannot be a substitute for searching the DNA space. Denton's insistence on the tampering with the DNA space as the main mechanism of 'directed evolution' conflicts with his rejection of unnatural interventions. Denton assumes manifold occurrences of tampering in the history of the cosmos and life:
1) tampering with the physical constants
2) tampering with the chemical properties of C,N,O,H, etc.
3) tampering with the selection of the 4 most efficient bases to be included in DNA
4) tampering with the structure of DNA (and proteins)
5) tampering with the DNA space
The last action surely is intervention. The bottomline is this: either fine tuning of initial conditions is sufficient for a biocentric universe or one needs tampering during the evolutionary process, which is intervention, which conflicts with his naturalism. Conclusion: impossible to fine tune the 4 bases A,T,C,G to produce directed evolution! In my view there is only one conclusion open for Denton: the designer of the 'Intelligent Design Theorists' (8). And what can I say more about Denton's evidence for directed evolution, than what Denton says himself (on another page): "Of course, these discoveries do not prove directed evolution" (p292).
Is Denton a Darwinist ? Above we saw that Denton accepted that organisms are genetically linked (common descent). In that sense he is an evolutionist and a Darwinist. However, in so far Denton accepts directed evolution, and in so far he accepts that the course of evolution is preprogrammed, and in so far he accepts Sheldrake-forces (p365), and in so far he defends foresight in evolution (p362), he rejects neo-Darwinism.
Is this the whole story? I cannot tell the whole story, because Michael Denton does not tell the whole story. The whole story includes answers to questions like: What about The Enigma of Life's Origin ? What about The Typological Perception of Nature ? What about The Fossil Record ? What about The Failure of Homology ? What about The Biochemical Echo of Typology ? (these are chapters in Evolution: A Theory in Crisis) (5). Since Denton does not tell us about it, the only thing I can do is read between the lines. In the 'Note to the Reader' Denton makes an important and revealing remark:
"Because the validity of the argument [biocentric design of the universe] depends on so many independent lines of evidence, the conclusion is not materially threatened because the whole picture is not yet complete or because this or that phenomenon such as the origin of life or the mechanism of evolution is not understood. Just as the meaning of a jigsaw puzzle may be obvious long before all the pieces are perfectly placed, so too my argument does not necessitate that everything be explained."
There is a second reason why problems with evolution do not have the impact they had in 1986 and that is the inevitability of life:
"that carbon-based life is therefore inevitable on any planetary surface where conditions permit it."(p265)
It should be clear that once the inevitability of the origin and evolution of life is accepted, all problems we have in understanding how it all happened, are not falsifications, but a sign of our own ignorance.
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