User:Former editor/EvoWiki/Positive Case for Design

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The Discovery Institute, perhaps to rebut charges that ID has no scientific content, released a document called The Positive Case for Design by Casey Luskin. Although it takes the form "Observations, predictions/hypotheses, experiments", it does NOT contain either predictions which differ from the mainstream evolutionary view, nor predictions which can ever falsify ID experimentally.

The essential problems with this ID argument are:

  1. It pretends that "Complex Specified Information" or "Irreducible Complexity" is falsifiable. In reality, these are defined only via an argument from ignorance.
  2. It predicts specific scientific "discoveries" which it is impossible to completely exclude:
    • It predicts that there are gaps, representing design intervention, somewhere in the fossil record.
    • It predicts that there is no junk DNA whatsoever.
    • It predicts that there are un-evolution-like convergences somewhere in the genomes of some organisms.

None of the points given should be considered a "positive" case for Intelligent Design; based on this document, ID could not be considered a falsifiable or scientific theory.

(Below, all bolded material is a quotation from The Positive Case for Design.)

Ways designers act when designing[edit]

  • (1) Intelligent agents think with an "end goal" in mind, allowing them to solve complex problems by taking many parts and arranging them in intricate patterns that perform a specific function (e.g. complex and specified information).
That is not a general statement. Sometimes, human designers act quasi-randomly, knowing only how to recognize something interesting when it emerges. For example, Benoit Mandelbrot's book "The Fractal Geometry of Nature" is a collection of esthetically pleasing, apparently complex images, selected from the output of essentially randomly-chosen equations. The only role of the "designer" was to recognize interesting results. This hypothesis is a false generality about designers.
  • (2) Intelligent agents can rapidly infuse large amounts of information into things.
Evolutionary processes can also infuse large amounts of information, as has been demonstrated many times analytically and in simulations. Thus, this hypothesis is equally true for intelligent design and for evolution.
  • (3) Intelligent agents 're-use' functional components that work over and over in different systems (e.g., wheels for cars and airplanes).
First of all, this is a generality about designers which may or may not be true. Evolutionary processes reuse (or, more correctly, "conserve") functional components from generation to generation. The existence of similar functional parts in diverse species may be evidence of either modular design by an intelligent designer, or evolution from a common precursor, or evolutionary convergence. Thus, this observation is equally true for intelligent design and for evolution.
Also important is that the pattern of re-use found in nature is a nested hierarchy. Bat wings are designed differently and have different features than bird wings. All bats have the one type, all birds the other. Intelligent agents do not limit themselves to changes in a single line. It would be unusual, for example, if the designers of automobiles had chosen to not put power steering in cars because it had already been put in trucks. Designers put features anywhere they will be useful. Nature copies elements only in hierarchical groupings. For instance, Kiwis are birds that have evolved to live a mammal-like lifestyle. They have modified feathers that act in many ways as fur, but they still have feathers, not fur. A designer would not likely create fur-like feathers for Kiwi, he'd give them fur.
  • (4) Intelligent agents typically create functional things (although we may sometimes think something is functionless, not realizing its true function).
This is an incorrect generality about designers; intelligent humans sometimes smash things, or doodle, or make mistakes, or allow things to decay. The statement "The intelligent designer designs things optimally", or "intelligent agents create only functional things" would have to be an axiom of the theory. At any rate, evolution in the most general sense does not make a specific prediction for the abundance of Junk DNA; once junk DNA is known to exist, evolution can make specific mathematical statements about how it changes across species. In any case, this statement is equally true for intelligent design (with or without the "optimum" axiom) and for evolution---evolution also "typically creates functional things", because functional things typically increase fitness, and nonfunctional things do not.

To summarize so far, the "observations" tend to assume, not a generic "intelligent designer", but one carefully tuned to create a world very similar to the evolutionary world---and, indeed, one free to mimic an evolutionary world in as much detail as He pleases.

Predictions of design (hypotheses)[edit]

  • (1) Natural structures will be found that contain many parts arranged in intricate patterns that perform a specific function (e.g. complex and specified information).
First of all, "specified function" is defined only a posteriori. Secondly, this does not follow from the stated observations; it assumes that only "intricate patterns" are capable of sustaining life. If simpler patterns suffice, an intelligent designer can use those. In any case, evolution is well-proven to be capable of making "intricate patterns that perform a specified function", and many such patterns have well-understood evolutionary histories. Thus, this "prediction" does not distinguish between the theories. (If the prediction only refers to " ... patterns for which an evolutionary history is not known", it becomes an Argument from Ignorance, and therefore invalid.)
  • (2) Forms containing large amounts of novel information will appear in the fossil record suddenly and without similar precursors.
This does not follow from the observation; it makes unstated assumptions about the rate and manner at which the hypothesized designer did his work. Experimentally speaking, it also assumes that "information" is discernible from the fossil record. For example, there is only a very small change in "information" between isolated bacteria and fibroid bacteria colonies, but the latter are much more likely to leave a fossil record. Thus, this "prediction" a) cannot be used to rule out ID even in principle (any record consistent with evolution could also be consistent with a slow-acting designer and a spotty record) and b) in the positive case, could only be verified given unrealistic level of detail in the fossil record. It's a God of the Gaps argument.
  • (3) Convergence will occur routinely. That is, genes and other functional parts will be re-used in different and unrelated organisms.
This also makes an assumption about the designer's motives; why couldn't the designer choose convergence or non-convergence in different cases? Evolution, on the other hand, makes very specific predictions about patterns of convergence; at the molecular level, convergence should be rare but not impossible. This "prediction" could be used to falsify evolution, but not ID; any degree of observed convergence, large or small, could be called consistent with an arbitrary designer.
  • (4) Much so-called "junk DNA" will turn out to perform valuable functions.
Again, this is true both in evolution and in ID; modern biologists certainly do not claim that all of the Junk DNA is useless, only that most of it is. This "prediction" thus has no bearing on the truth or falsehood of either evolution or ID, although a demonstration that the DNA truly is "junk" could falsify the "optimization axiom".

To summarize, none of these predictions offer any chance to falsify ID. Any possible result for the observations, positive or negative, can be called consistent with the design hypothesis. In other words, they are not predictions at all.

Examining the evidence[edit]

  • (1) Natural structures have been found that contain many parts arranged in intricate patterns that perform a specific function (e.g. complex and specified information), such as certain irreducibly complex machines within the cell. The bacterial flagellum is a prime example. The specified complexity of the simplest, self-reproducing cell is another.
This is true. However, as shown in the rebuttals above, this does not provide any evidence for or against ID.
  • (2) Biological complexity (i.e. new phyla) appear in the fossil record suddenly and without similar precursors. The Cambrian explosion is the prime example.
No it isn't. There are complex fossils in Precambrian strata. New types of organisms arose in the Cambrian over five to ten million years, in a fashion perfectly consistent with evolution. A collection of references on this point can be found at http://www.talkorigins.org/indexcc/CC/CC300.html.
  • (3) Similar parts have been found in organisms that Darwinists themselves see as separated by more closely related forms that do not contain the similar parts in question. Clear examples include genes controlling eye or limb growth in different organisms whose alleged common ancestors are not thought to have had such forms of eyes or limbs.
As noted, rare accidental convergences are expected in evolution; very large amounts of convergence are expected in related organisms. As the document does not cite any sources, it is impossible to evaluate this claim of evidence. (Note: Mr. Luskin later privately cited the Pax-6 gene as an example. This gene has a clear case for common ancestry; the only question is when it acquired its apparently eye-specific regulatory role. See http://www.pnas.org/cgi/content/full/94/6/2098.)
  • (4) Increased knowledge of genetics continues to uncover functions for various strands of "junk-DNA." Examples include functionality in some pseudogenes, microRNAs, introns, LINE and ALU elements. Examples of DNA of unknown function persist, but design theory encourages researchers to uncover as yet unknown function whereas Darwinian theory invites scientists to shrug and assume that apparently functionless DNA is useless.
Biologists make no a priori assumptions about the functionality of this DNA, and indeed the new functions that are being discovered (sometimes in evolutionary biology labs) are perfectly consistent with evolution. In any case, the vast amount of remaining "junk DNA" should be considered a contradiction of prediction 4. (The ID advocates may claim that "the jury is still out", because scientists may eventually find some role for this DNA. However, if the jury is able to remain "out" forever, then the "prediction" is a useless one, being inaccessible to experiment.) Once again, though, this piece of "evidence" neither confirms not falsifies intelligent design theory, because it is claimed in support of an unscientific "observation" and inconclusive hypothesis.

To summarize the experimental section, these experiments are all proposed "fulfillments" of indeterminate predictions, and have nothing to say for or against ID.

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