From: Ted Davis (TDavis@messiah.edu)
Date: Mon Aug 11 2003 - 13:05:09 EDT
I've only recently returned to this list, so I may have missed an important
earlier point or two. Let me jump in anway:
I agree that the sentence quoted below comes from the end of the
introduction to Darwin's first edition. Yet there is much truth in what
Michael wrote. Darwin clearly envisioned an evolutionary process that
involved billions of years--he thought that the erosion of southwestern
England had taken around 300 my, the only number of that kind he offered in
the first edition of the Origin. Darwin was nonplussed by what the
quantitative scientists (physicists, geologists, astronomers) were coming up
with, for upper limits on the ages of the earth and the sun. And he did
make very significant changes in later editions of the Origin and in the
Descent of Man. These included at least, removing his 300 my estimate and
inventing (in the Descent) a hypothesis about "'pangenesis," a mechanism
whereby some acquired characteristics could be inherited in the next
generation. It is difficult not to interpret these as implicit
acknowledgement of the force of the argument against his seat of the pants
conception of a very old earth.
ted
>>> Walter Hicks <wallyshoes@mindspring.com> 08/11/03 12:33PM >>>
Michael,
Both you and Glenn Morton imply that this was
backtracking from his original position. This is
not the case, since he was quoting his original
contention in the first edition. I quote from the
introduction of that first edition.
"I am fully convinced that species are not
immutable; but that those belonging to what are
called the same genera are lineal descendants of
some other and generally extinct species, in the
same manner as the acknowledged varieties of any
one species are the descendants of that species.
Furthermore, I am convinced that Natural Selection
has been the main but not exclusive means of
modification."
What he did not say is that species arose from
anything other than natural descent. That would
apply no matter what Kelvin's time frame was.
However, the total exclusivity of natural
selection as a mechanism is something he dienies
in the first edition and then emphasices in the
6th edition.
It is nice for mind readers to tell us what he
really thought, but why not take him at his word?
I really have no desire to read a complete book on
the subject but would welcome any insights you
could provide from your own readings.
Walt
Michael Roberts wrote:
> Part of the reason Darwin back-tracked over Nat
> Selection was the shortness of geological time
> insisted on by Lord Kelvin and others where
> 100my was seen as the upper limit. Thus there
> was too little time for NS to do its work.
> Kelvin was wrong and also Darwin in giving into
> a mere physicist. See Joe Burchfield's books and
> articles on this Michael
===================================
Walt Hicks <wallyshoes@mindspring.com>
In any consistent theory, there must
exist true but not provable statements.
(Godel's Theorem)
You can only find the truth with logic
If you have already found the truth
without it. (G.K. Chesterton)
===================================
This archive was generated by hypermail 2.1.4 : Mon Aug 11 2003 - 13:04:10 EDT