--------
Thanks to Mark Phillips for his careful review of my "fits the data..."
critique.
I want to start with his concluding paragraph:
MP> I agree that PC and TE seem to fit the data equally well. It seems to
> me, contrary to your claim, that both have about the same number of
> degrees of freedom. It may be that biological evolutionary theory
> achieves a firm empirical grounding - but it hasn't done so yet.
> Let's not jump the gun. There are theological arguments suggesting
> that PC might be right, not conclusive perhaps, but reason enough for
> not discarding PC prematurely. Naturalistic evolutionists have
> overplayed their hand - this should be pointed out. Let us not be
> guilty of the same by dismissing evolution without due cause, but let
> us also be honest about the exact state of knowledge about origins,
> and not feel pressured to jump one way or the other unless there are
> good reasons to do so.
This sounds very fair to me.
I strongly encourage Christians who write books and publically debate
about evolution to present BOTH Progressive Creation AND Theistic
Evolution as genuine alternatives to Naturalistic Evolution. I encourage
you to explain how BOTH P.C. and T.E. arise out of Christian
theology, and how both stand against Naturalism's unwarranted
extrapolations. If you also explain how P.C. and T.E. differ from differ
from each other in their scientific predictions, and how this offers a
genuine flexibility to the Christian investigator which is unavailable to
the atheist, that should make a powerful presentation!
I strongly DIScourage Christians who write books and publically debate
about evolution from presenting Progressive Creation (with miraculous
interventions from God to bridge gaps in the biological developmental
history) as the ONLY Christian alternative to Naturalistic Evolution,
while simultaneously dismissing Theistic Evolution as unworthy of
consideration and as a theology corrupted by philosophical naturalism.
--------------
Now, to the main part of Mark's review:
MP> Loren tells us that Progressive Creation is basically Theistic
> Evolution with an "extra degree of freedom". He also explains how it
> is not always a good idea to add an extra degree of freedom simply
> because it fits the data better.
>
> The first thing I would like to note is that there is no "right" way
> to do data fitting. The theory of data fitting is half based on
> logic, the other half on heuristics (rules of thumb). We have
> developed these heuristics because "they seem to work", not because
> they are inherently the right thing to do. This does not completely
> invalidate Loren's points about data fitting, but it does mean we need
> to think very carefully about it.
This is a good point.
(1) Progressive Creation is sometimes presented this way: We believe God
performed supernatural miracles at various points in the developmental
history of plants and animals. (Some obvious suspects include the origin
of life, the origin of higher taxa, the origin of complex physiological or
biochemical structures, the origin of "new" genetic information to code
"new" protein families.) However, we're not going to firmly predict WHICH
ones required supernatural activity from God. If and when scientists find
a "naturalistic" explanation for any of those "suspect" areas, it's no big
deal, the Progressive Creation hypothesis remains unchanged.
This formulation, I think you'll agree, can be characterized as "Theistic
Evolution with an extra degree of freedom."
(2) Other times, I'm happy to say, advocates of Progressive Creation go
out on a limb and predict WHICH elements of biology's developmental
history they believe MUST have been supernatural and WILL NEVER BE
explainable by natural mechanisms. THIS form of Progressive Creation, I
would say, has (roughly) the same "degrees of freedom" as Theistic
Evolution.
The claims that "origins-of-life/origins-of-phyla/
origins-of-new-genetic-information/etc. will NEVER be explainable in terms
of natural mechanisms" are far from proved; they are intuitive guesses
based on sketchy data. Likewise, claims that "they WILL eventually be
explainable in terms of natural mechanisms" are equally intuitive guesses
based on sketchy data. Neither one seems to fit the currently available
scientific data noteably better than the other. (Although I do have my
preference, which you can guess. :-)
MP> Evolution seems to have quite a few degrees of freedom. Evolution
> claims that life came about through the process of one animal evolving
> through a series of small morphological changes into another animal
> (or in fact, several other animal species). As far as I know, it
> doesn't say very much about what _morphological_paths_ these
> transitions must travel along. So it seems to me that there are
> plenty of degrees of freedom here.
> [...]
> The problem is that we currently have only a small idea of how change
> in DNA gives rise to change in morphology. As a result, it places few
> restrictions on morphological transition - in fact, perhaps it
> actually has more of degrees of freedom than Darwin's original theory.
> Genetics tells us that we should expect some amount of morphological
> change through DNA change, but until we know more about the
> relationship between DNA and morphology, it doesn't say much about how
> large scale transitions would occur, or even if they would be
> possible.
Minor point: We can already set SOME limits on the rates of mutation and
substitution. If, for example, cows had a wildly different number of
chromosomes from camels, if the locations and sequences of the active
genes were all mixed up relative to each other, if the developmental
program showed wide divergences, and if there was no homology in
non-coding sequences of DNA (introns, pseudogenes, etc.), then the
combination of fossil records and genetics could pretty much rule out
common ancestry. If camel fossils appeared "recently" and camel DNA
showed wide divergence (in location of genes, non-coding sequences, etc.)
from any other living organism, it would be reasonable to rule out _any_
evolutionary scenario for camel origins.
However, as you point out, we don't know of any such extreme situations,
and evolutionary theory still has a lot of "wiggle room" due to our
current level of ignorance.
> Are there any theological reasons to support PC?
> ------------------------------------------------
> Loren raised the Genesis 1 account. I am running out of time, so I
> will leave that for now. However, I can think of a different
> theological reason for at least considering PC, and that is the
> occurence of supernatural miracles in scripture.
> [...]
> Just as our observance of lots of linear relationships in the world
> leads us to think that linear interpolation might be a good thing to
> do, so too, our observance of supernatural miracles in the world and
> in scripture can lead us to think that Progressive Creation might be a
> good model.
You are absolutely correct: God's use of miracles (with human witnesses)
during the "history of Salvation" gives us a very good reason to expect
that God MIGHT have used miracles in the developmental history of plants
and animals.
On the other hand, the Bible _also_ depicts God as actively shaping and
governing his creation in phenomena which we believe are actualized by the
regular and continuous operation of natural mechanisms. (Isaiah 55:10
readily comes to mind, since I'm memorizing that chapter at the moment.
There are other examples.) The evidence that God used the regular and
continuous operation of natural mechanisms over billions of years to
create physical structures such as the galaxy, the sun, and an earth
suitable to support life, combined with the evidence that God uses the
regular and continuous operation of natural mechanisms in his day-to-day
governance of such complex biological phenomenea as zygotic development
(the means by which new individual plants and animals develop) and
microevolution (the means by which species adapt to their environment),
gives us a very good reason to expect that God MIGHT have used the regular
and continuous operation of natural mechanisms over time to create the
past and present biological lifeforms.
So I do not see the theological data strongly favoring P.C. over T.E., or
vice-versa.
--------------------------------------------------------------------------------
"You should always save hyperbole |
until you really need it." | Loren Haarsma
--Hobbes (_Calvin_and_Hobbes_) | lhaarsma@opal.tufts.edu