To: Jeffrey Lee <jlee@isisph.com>, "ASA" <asa@calvin.edu>
cc: (bcc: James Taggart/Multilink)
Subject: Re: Intell. Design
Jeffrey Lee wrote:
...[snip]
but that the system is so
complex that all of the right DNA sequences would have to come into being
simultaneously for the system to work. In other words, he stipulates to
the existence of the paper and blue ink and the 2X4's, drywall, etc., but
argues that the design itself cannot happen gradually or by chance (a
dangerous choice of words, I realize).
And you responded:
I am going to re-post a note I did back in 1996. The very same argument
you just made can be made about the world's economy. If you remove a
piece, it doesn't work. Yet we KNOW from history that the economy evolved
to its present irreducibly complex state. The irreducible complexity
argument is not very good.
While I am a believer in evolution, there are parts of the puzzle that seem
to me to be irreducibly complex, despite your contrary view. The one that
puzzles me the most is the lense of an eye. I can imagine the evolutionary
process that would give rise to vision: first a few epithelial cells that
are light sensitive. This sensitivity confers an evolutionary advantage
that favors increasing the number of light sensitive cells. These cells
might even become configured in such a way that the eye formed a "pin-hole"
camera view of the world. But where does the lense come in? Unless it was
initially formed in a completely functional state (could be the lense like
that in a human or one of those segmented lenses that bees have), I can't
see how it would not make vision poorer rather than better. If it was just
a prototype (as the initial light sensitive cells are prototypical eyes),
then it would convey no advantage, so why would it evolve? It seems
unlikely to me that the lense evolved first, then the light sensitive
cells, because what would the function of the lense be without a field to
focus the light on. That leaves what must be the most likely third choice
where the lense and eye evolved together. However, given that vision must
have arisen from the light sensitive cells I postulated above, they would
need to be configured in such a way that even a prototype lense could
function. That implies some further differentiation of the proto-optic
cells before the light sensitivity comes into play. Seems mighty complex
to me. The final complexity is that it seems likely that vision has
evolved independently several times. What is the "natural" explanation?