Apart from the fact that you can't count (2 paragraphs numbered 7), I'm
glad you attached Bill's opus. To simplify understanding my comments, I
put the relevant portions before my comments.
4. The testability objection to intelligent design can be interpreted in
two ways. One is to claim that intelligent design is in principle
untestable. This seems to have been Scott's line in the early nineties.
Certainly it is a
hallmark of science that any of its claims be subject to revision or
refutation on the basis of new evidence or further theoretical insight.
If this is what one means by testability, then design is certainly
testable. Indeed, it was in this sense that Darwin tested William Paley's
account of design and found it wanting. It simply won't wash to say that
design isn't testable and then in the same breath say that Darwin tested
design and refuted it.
This is not true. If Darwin found Paley's argument as not empirically
falsifiable, he would have one of the standard tests that it is not
scientific.
5 . The other way to interpret the testability objection is to claim
that intelligent design may in principle be testable, but that no tests
have been proposed to date. This seems to be Scott's line currently.
Indeed, if the testability objection is to bear any weight, its force
must reside in the absence of concrete proposals for testing intelligent
design. Are such proposals indeed lacking? Rather than looking solely at
the testability of intelligent design, I want also to consider the
testability of Darwinism. By comparing the testability of the two
theories, it will become evident that even the more charitable
interpretation of Scott's testability objection does not hold up.
On the testability of ID, I have asked what difference there would be in
any empirical theory. I know of none.
Here I put two paragraphs together, including the first one numbered 7.
The second 7 follows.
7. What then are we to make of the testability of both intelligent
design and Darwinism taken not in a generic abstract sense but
concretely? What are the specific tests for intelligent design? What are
the specific tests for Darwinism? And how do the two theories compare in
terms of testability? To answer these questions, let's run through
several aspects of testability, beginning with falsifiability.
PREDICTABILITY:
21. Another aspect of testability is predictability. A good scientific
theory, we are told, is one that predicts things. If it predicts things
that don't happen, then it is tested and found wanting. If it predicts
things that do happen, then it is tested and regarded as successful. If
it doesn't predict things, however, what then? Often with theories that
try to account for features of natural history, prediction gets
generalized to include retrodiction, in which a theory also specifies
what the past should look like. Darwinism is said to apply retrodictively
to the fossil record and predictively in experiments that place an
organism under selection pressures and attempt to induce some adaptive
change. But in fact Darwinism does not retrodict the fossil record.
Natural selection and random variation applied to single-celled organisms
offers no insight at all into whether we can expect multi-celled
organisms, much less whether evolution will produce the various
body-plans of which natural history has left us a record. At best one can
say that there is consilience, i.e., that the broad sweep of evolutionary
history as displayed in the fossil record is consistent with Darwinian
evolution. Design theorists strongly dispute this as well (pointing
especially to the Cambrian explosion). But detailed retrodiction and
detailed prediction are not virtues of Darwin's theory. Organisms placed
under selection pressures either adapt or go extinct. Except in the
simplest cases where there is, say, some point mutation that reliably
confers antibiotic resistance on a bacterium, Darwin's theory has no way
of predicting just what sorts of adaptive changes will occur. "Adapt or
go extinct" is not a prediction of Darwin's theory but an axiom that can
be reasoned out independently.
Darwin predicts a relationship among living things. The only thing he had
to go on was either gross anatomy or what little was known of cell
structure. Witness, for example, the phylum Radiata, for coelenterates,
ctenophores and elasmobranchs. In contrast, modern genetics has found
similar genes doing similar things across families, orders, classes and
even phyla. It also predicts that a section of a chromosome may be
duplicated and genes on one of the duplications either silenced or
modified by mutation or recombination to take on a different task. Such
has been found, despite the fact that we have complete sequences for very
few organisms. What has not been found is a mechanism adequate to
originate life. Unfortunately, no one today can predict with certainty
either that it will eventually be found or that it cannot be found, for
it never existed. The latter is required for ID as I have found it
presented.
FALSIFIABILITY:
7. Is intelligent design falsifiable? Is Darwinism falsifiable? Yes to
the first question, no to the second. Intelligent design is eminently
falsifiable. Specified complexity in general and irreducible complexity
in biology are within the theory of intelligent design the key markers of
intelligent agency. If it could be shown that biological systems like the
bacterial flagellum that are wonderfully complex, elegant, and integrated
could have been formed by a gradual Darwinian process (which by
definition is non-telic), then intelligent design would be falsified on
the general grounds that one doesn't invoke intelligent causes when
purely natural causes will do. In that case Occam's razor finishes off
intelligent design quite nicely.
If there were no continuity in genes, Darwinism would be false. Darwin
didn't know about genes, but we do.
8. On the other hand, falsifying Darwinism seems effectively impossible.
To do so one must show that no conceivable Darwinian pathway could have
led to a given biological structure.
This is false, as noted above. Additionally, given any set of empirical
data, we can have an infinite number of equally good models. So "no
conceivable Darwinian pathway" is impossible of attainment.
9. The fact is that for complex systems like the bacterial flagellum no
biologist has or is anywhere close to reconstructing its history in
Darwinian terms. Is Darwinian theory therefore falsified? Hardly. I have
yet to witness one committed Darwinist concede that any feature of nature
might even in principle provide countervailing evidence to Darwinism. In
place of such a concession one is instead always treated to an admission
of ignorance. Thus it's not that Darwinism has been falsified or
disconfirmed, but that we simply don't know enough about the biological
system in question and its historical context to determine how the
Darwinian mechanism might have produced it.
"I have no proof" is not equivalent to "There is no proof," so this is
specious. Fermat's Last Theorem and the Four Color Theorem remained
unproved for centuries, but today they stand proved.
CONFIRMATION:
12. What about positive evidence for intelligent design and Darwinism?
From the design theorist's perspective, the positive evidence for
Darwinism is confined to small-scale evolutionary changes like insects
developing insecticide resistance. This is not to deny large-scale
evolutionary changes, but it is to deny that the Darwinian mechanism can
account for them. Evidence like that for insecticide resistance confirms
the Darwinian selection mechanism for small-scale changes, but hardly
warrants the grand extrapolation that Darwinists want.
This strikes me as assuming that we now know _all_ about origins.
16. Now what's significant about a sequence of prime numbers from outer
space is that they exhibit specified complexity -- there has to be a long
sequence (hence complexity) and it needs to display an independently
given pattern (hence specificity). But what if specified complexity is
also exhibited in actual biological systems? In fact it is -- notably in
the bacterial flagellum. Internet mavens have been pestering me for
actual calculations of complexity involved in such systems. I address
this in my forthcoming book (No Free Lunch), but such calculations are
out there in the literature (cf. the work of Hubert Yockey, Robert Sauer,
Peter R|st, Paul Erbrich, Siegfried Scherer, and most recently Douglas
Axe -- I'm not enlisting these individuals as design advocates but merely
pointing out that methods for determining specified complexity are
already part of biology).
What is assumed here is a purely random origin. But may there be
biochemical patterns? unexplored conditions? Do we know enough to do the
computations, or is this like the claim that bumblebees can't fly?
24. It's evident, then, that Darwin's theory has virtually no predictive
power. Insofar as it offers predictions, they are either extremely
general, concerning the broad sweep of natural history and in that
respect quite questionable (Why else would Stephen Jay Gould and Niles
Eldredge need to introduce punctuated equilibria if the fossil record
were such an overwhelming vindication of Darwinism?); and when the
predictions are not extremely general they are extremely specific and
picayune, dealing with small-scale adaptive changes. Newton was able to
predict the path that a planet traces out. Darwin's disciples can neither
predict nor retrodict the pathways that organisms trace out in the course
of natural history.
The parenthetical sentence indicates the foolish assumption that science
must be always right, not subject to change. What history of science has
Dembski been reading?
28. First off, let's be clear that design can accommodate all the
results of Darwinism. Intelligent design does not repudiate the Darwinian
mechanism. It merely assigns it a lower status than Darwinism does. The
Darwinian mechanism does operate in nature and insofar as it does, design
can live with its deliverances. Even if the Darwinian mechanism could be
shown to do all the design work for which design theorists want to invoke
design (say for the bacterial flagellum), a design-theoretic framework
would not destroy any valid findings of science. To be sure, design would
then become superfluous, but it would not become contradictory or
self-refuting.
This is a curious admission. Design is superfluous, without empirical
relevance, and therefore nonscientific unless science is redefined. Isn't
this precisely what critics of ID have insisted all along? Of course,
this is not what Philip Johnson has proclaimed.
Dave
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