On the third point, it seems to me the biggest problem is that young earth
creationists (YEC's) see the Biblically orthodox interpretation of Genesis
as a fixed point rather than a circle of freedom within which Christians can
move and still be true to the faith. (I borrowed the concept from Francis
Schaeffer.) Although they may disagree on the exact boundaries, many
conservative theologians such as B.B. Warfield, Gleason Archer, Francis
Schaeffer, etc. have drawn circles of freedom in this area rather than fixed
point interpretations. When looking at science, I think we should explore
all possibilities that lie within the Biblical circle of freedom. Based on
my reading of the above theologians, this includes "old earth creationism"
and at least some forms of "theistic evolution".
Now, having said that I agree with Glenn on a lot of points, I would like to
offer some criticisms of his probability post.
1) Glenn, in his analogy between a functional sentence and a functional
protein, assumes the existance of letters (amino acids). In fact, in a true
abiogenesis scenerio, the existance of amino acids are not a given. Glenn's
post ignores the probability of generating the 20 amino acids from their
component parts even though this must be included in the total probability
of generating a functional protein from scratch. It is not a trivial
exercise to form large concentrations of the 20 amino acids using only the
starting materials and energy sources present upon the early earth.
2) In fact, each of the 20 amino acids has two enantiomers (optical
isomers). The functionality of proteins depends upon their organization in
3-D space. But in order to form the alpha helix and beta sheet structures,
you need all (or a very large percentage) of one optical isomer. However,
in any plausible abiogenesis scenerio, both enantiomers are present in equal
quantities in the prebiotic soup. For the non-chemists in the crowd,
enantiomers are mirror images of each other like your right and left hands.
In Glenn's analogy, they would be backwards letters (see below). Thus, in
Glenn's alphabet soup, there are 20 functional letters and 20 backwards
letters and the inclusion of any backwards letter into a sentence destroys
the functionality of the sentence. Needless to say, this strongly decreases
the probability of a functional sentence.
__ __
__| |__
__| |__
3) Glenn's shortest funtional sentence is eight letters, but there are no
functional proteins of eight amino acids. I don't know what the length of
the shortest functional protein is, but I'm guessing it would have to be at
least an order of magnitude higher (80 AA). If generating a functional
protein is as easy as Glenn's scenerio implies, all we would have to do is
fill a bunch of vats up with amino acids in a mild aqueous solution, warm
them up a bit and pull out all kinds of functional proteins. It is my
understanding that people have been working on this kind of stuff since the
1950's and it just isn't that simple.
4) It may be true that under "just right" conditions that the spontaneous
generation of a functional protein is inevitable if given some time and a
decent amount of starting material. But were these conditions actually
present upon the early earth? And, if so, why did the incredibly unusual
circumstances perfect for the formation of life occur instead of the
millions of other hostile scenerios? This doesn't destroy the probability
argument, but simply moves it to a new arena. (The the probability of
favorable initial starting conditions also appears to be very small.)
I am not an expert in the whole area of probability and abiogenesis. But I
don't think the issue is as simple as either Duane Gish or Glenn Morton's
scenerio suggest. In my opinion, a good solid reference that is skeptical
of abiogenesis but is sensitive to the complexity of the issues involved is
Thaxton C.B., Bradley W.L. & Olsen R.L., "The Mystery of Life's Origin:
Reassessing Current Theories". They did a much better job of stating the
difficulties of abiogenesis than I can.
__________________________________________________________
"Looking back, there's a thread of love and grace
Connecting each line and space I've known" -David Meece
==========================================================
Eddie Gene Olmstead, Jr. Chemistry Department
Asst. Professor of Chemistry Gordon College
Email: olmstead@gordonc.edu 255 Grapevine Road
Phone: (508) 927-2300 Ext. 4393 Wenham, MA 01984