Hello Ian,
You wrote (back on Feb-14)
[...]
>(1) First of all, it doesn't prove we are all descended from a single
>ancestor, as the following argument shows. Most people today tend to use
>PC's running one of Microsoft's operating systems (apologies for offending
>any Mac or Unix users out there ;-). Such systems run a great diversity of
>different programs; Word processors, Spreadsheets, E-mail clients, Browsers,
>Graphics packages, etc. Furthermore almost all of these programs have a
>menu-bar at the top, with such items as "File" , "Edit", etc. These menu
>bars all function in the same way. You click on the word with your mouse
>pointer, and up pops a list of options. All of these functions are produced
>by the same bit of computer code. If one were to disassemble the machine
>code, and figure out what happens when a menu pops up, you would find it was
>always the same set of instructions being obeyed, no matter what the program
>you tried it on. This is, of course not surprising; the functionality is all
>contained in "library code" which is used in all programs. As I have
>developed programs in to run under Microsoft Windows, I can tell you that in
>any moderate sized program you develop, 80-90% of the code is in fact taken
>up by such library code, that you didn't write. (A lot is needed; simple
>things like formatting text, filling pixels on screens when you hit a
>button, drawing lines and so forth). The new stuff that you wrote, to make
>your own program with its own very specific function constitutes
>approximately 10% of the code. I hope the analogy is clear from the above.
>
>So on the basis of the "common Genetic code" argument, we are supposed to
>draw the conclusion that all Microsoft Windows programs evolved from a
>common ancestor? That there was one functioning program that did, we don't
>know what; call it "ADAM.EXE". Then all programmers from there onwards took
>copies of the source code of ADAM.EXE, and modified them slightly and passed
>it on to others. Gradually there was a branching, and one branch led to
>Word for Windows, and another led to Excel, and so forth. And that someone
>at Corel pinched the source code of Word for Windows and evolved it into
>Corel Draw.
>
>Of course it didn't happen like that. What happened was that a clever
>programmer at Microsoft designed a standard set of tools (known as the
>"Windows Applications Programming Interface" (API) for short, without any
>particular application in mind, but which would be of general use to other
>developers, who then pick up the tools, and develop from scratch a word
>processor, or a spreadsheet, or whatever they wanted.
>
>What is going on here is similar, I suggest, to the Creationist model. God
>creates a diverse variety of life forms, having first designed His own
>"API", a set of genetic code sequences that perform basic functions for
>cells in all different life forms (such as generating energy, assisting in
>the replication of DNA, etc).
I have difficulties with the "common design" argument as it is often
applied. I think it works "backwards". It doesn't delimit or imply
anything about what one may expect to see in biological systems. Instead,
it can only serve to delimit how God (or your favorite, proximate designer)
behaves.
From the view of science, one can start with observations about
biology and try to apply it to a physical process like evolution
(and visa versa). That's because there are physical limitations
and knowable regularities at work. Opinions may vary on the relative
success of this work, but at least such a question is scientifically
approachable. However, starting with the hypothesis of active design,
it's hard to make any general statements about what one might expect
to see in biology. Any observations made and applied to a designer
can only tell us about the choices made by a designer.
Science may tell us something about a designer (& its plans), but
starting with the notion of a designer provides little information
about science. The "flow of explanation" is, unfortunately, mostly
one-way.
We know from observation that morphological similarity does not require
genetic or biochemical similarity. Also, if species or groups of similar
organisms are not related by descent but are instead separately designed,
then there is no a priori reason for them to share common genetics or
biochemistry. That is because biochemical systems can be extremely flexible.
Even with our primitive technology, we can move, reorder, and even substitute
new sequences in place of old ones (And we can leave rather obvious
"fingerprints" on what we've done. If we had far superior technological
understanding, as the proximate designers favored by ID'ers are thought to
have, there are no physical limitations which would necessarily confine all
the organisms to the general pattern of nested hierarchy we currently see.
Or to put it another way: Let's assume that we can explore all of the
potential "genome space" to find sequences that produce giraffe-like
organisms. That subset is much smaller than all of genome-space but
it still contains many sub-spaces with very dissimilar sequences, many
of which could not be accessed by a mechanism which relies on links
between viable organisms. So, how many genomes can make a giraffe?
Many. How many of these genomes are accessible by links through common
descent from previously existing organisms on earth? Far, far fewer.
What does this mean? If, of the set of equally viable "giraffe" genomes,
a single could be chosen at random for "expression" on Earth, then we
would not expect to see it fit into a nested hierarchy of life.
That is not to say that proximate designers cannot choose designs that
fit into hierarchical patterns. They could. However, observations of such
patterns only tell us about the choices made by the designers. It's not
particularly informative about biology.
>Later on in the Telegraph, Sulston is quoted directly "It is the unity of
>life, or Nature being conservative, or the idea of the Blind Watchmaker -
>the notion of evolution as a constant reworking or random recombining of
>parts". But I don't think the alternative; that it is God, rather than
>Nature being conservative; the Sighted Watchmaker, if you like, is any more
>implausible or inconsistent with the "common code" evidence.
[...]
The common-toolbox analogy is neither plausible or implausible, nor is
it consistent or inconsistent. It's simply a post-hoc rationalization
of an observation. I don't see how one can start with the notion of
a potentially omnipotent designer and *not* find an explanation that
fits any observation (FWIW - The philosophy of science dude, Elliott
Sober worked through this problem of design and science a while ago).
So, if you're using the observation of biological commonality to try
to understand the mind of a designer, that's fine. But going the
other way, trying to understand biology based on the mind of a
omnipotent (or merely a very potent) designer, well, that's proven
to be historically and scientifically unproductive so far.
Interestingly, I think biological dissimilarities would carry more
weight if one was arguing for obvious intrusions from a proximate
designer. Certainly, that's an approach used by many in the ID
movement. Hmm... couldn't one argue that a designer chose to use
common patterns with just that intention in mind (hiding its hand to
make way for the possibility of faith rather than heavy-handed
compulsion)?
Regards,
Tim Ikeda
tikeda@sprintmail.com
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