The thread on theory has been one of the most
productive sequences I have had the pleasure to
read, with many insightful and stimulating posts.
I, too, worry about wearing out my welcome,
particularly with respect to the burden placed on
David, who, I think, may not realize what an
immensely valuable service he provides. I value
ECOLOG precisely because of its free-wheeling
informality and open nature, and it is one of the
most civilized (in no small part because of
David's wise moderation of extremes) lists on the
Internet. (It's the only list to which I still
subscribe.) When one thinks of >6K subscribers
across the world all sharing so generously of
their knowledge, it is truly a rare
treasure. When I think of David having to read
thousands of posts and decide which to post and
not to post, I marvel at his patience,
perseverance, and wisdom, and think perhaps that
at some point certain discussions of apparently
limited interest should perhaps be taken
off-list. Then I wonder about those thousands of
silent "lurkers" who might benefit, I think, no,
David will call a halt when it gets too be just
too much. But then, we who post more than the
average, should not put him on that spot, so I
understand the gracefulness of people like Bill
and Wirt and others who seem to have some sixth
(or seventh?) sense about when a discussion is
losing steam. Perhaps those who still have
something to say beyond this point should
continue off-list, then when they are "finished"
post the entire thread as one, or? Other ideas?
So, however it goes, I am grateful for this list
and all of the posts, even if I don't read them
all. And mostly to David. I'd like to hear David's guidance on this.
WT
At 12:21 PM 2/22/2008, William Silvert wrote:
Hey this is fun, and informative, so until the
boss tells us to lay off I'll put in a bit more.
First of all, definition of prediction, which is
causing some confusion. Wiki has a nice opening
section, with the definition: "A prediction is a
statement or claim that a particular event will
occur in the future in more certain terms than a
forecast. The etymology of this word is Latin
(from præ- "before" plus dicere "to say").", and
I had in mind the idea of predicting the future,
not confirming the past -- as Niels Bohr said,
"Prediction is very difficult, especially if
it's about the future.". I thus pointed out that
astronomy is not very good at predicting the
future, although of course it predicts the
results of experiments to see what has already
happened. A lot depends on whether we consider
making testable statements about events as long
ago as 12 billion years counts as prediction! So
if we drop the distinction between prediction
and confirmation, I don't think that there is any real dispute going on.
In terms of the initial discussion about theory
vs. experiment, I was just reminded of the
"discovery" of the neutrino. Theorists claim
that mass-energy and momentum are conserved, but
in beta decay, where a nucleus emits an
electron, this is not the case experimentally.
So did the theorists throw out the theory?
Heavens no, they simply said that there was some
other undetectable particle emitted during the
decay process that ran off with the missing
energy and momentum. Talk about fudging your
results! It took 26 years for anyone to actually
claim to detect a neutrino, but that did not
seem to bother physicists. Wirt just posted a
decription of WIMPs, more mysterious material
whose existence is postulated simply because
experimental results conflict with theory.
Although this physics stuff may seem a trifle
esoteric, the same situation can occur in
ecology. I remember once participating at a
workshop to study the ecosystem of a bay where I
noticed that the measured secondary production
was higher than primary production. When I
suggested that we needed to calculate the flux
of plankton into the bay I had problems
convincing my colleagues that the problem was
that something was missing from the experimental
study, and not that we should jettison the idea
of conservation of energy (and there are
ecologists who claim that living organisms do
not necessarily have to obey the law of conservation of energy).
Another case which has never been fully resolved
had to do with toxin uptake by shellfish. In
some cases if I take all the experimental data
and calculate the toxin load I cannot generate
levels as high as are observed. When I try to
convince the experimentalists that some of the
measurements must be wrong, they insist that the
fault must lie with the theory -- but no one has
ever come up with a theory that explains how
shellfish can accumulate more toxin than they
ingest (and the experiments rule out biotransformation).
Bill Silvert
