This is a tricky subject. It is easier to deal with conventional data
from instrument.
Mark Iverson wrote:
So what? Here's a place that has 31,072 petition signatures, all
with degrees, nearly half with
PhDs/MDs.
Science is NOT done by concensus!
We all agree that science is not a popularity contest (not done by
consensus, that is). Yet at the same time, the opinions of experts
matter. You should respect experts in groups, and lone experts who
disagree with the mainstream. You should never dismiss an expert out
of hand. They are sometimes wrong, but often right. Very often you
don't know enough to judge. It gets worse: often you cannot tell who
is an expert. In extreme cases, people such as Robert Park mistakenly
believe themselves to be experts in subjects they know nothing about!
As Nick Palmer and I have pointed out this leads to a Fallacious
Appeal to Authority. See:
http://www.nizkor.org/features/fallacies/appeal-to-authority.html
Based on Palmer's description, this Oregon petition apparently falls
in that category. You could take a poll of "PhD scientists" about
cold fusion and come up with similar meaningless results. People who
have not read the literature and people from unrelated fields must be
excluded from a serious opinion survey of experts. I do not know how
many people in the Oregon petition are in this category. I would have
to find out before judging the validity of this petition. It sounds
fishy, but who knows?
Of course anyone -- scientist or not -- has the right to sign a
petition. The views of all citizens should be respected. But a
political petition about global warming is not scientific evidence,
and should not be confused with it. A petition signed by actual
experts in global warming is one kind of scientific evidence. It is
evidence once removed, or "secondary," or evidence of evidence, if you will.
In March 1989, you would have been foolish to assume that cold fusion
is real just because Martin Fleischmann was president of the
electrochemical society and an FRS etc. On the other hand, you would
be foolish to dismiss it out of hand, given his qualifications, and Pons'.
Because those two were experts, other experts took them seriously,
and attempted applications. After a few years, ~100 groups of these
experts succeeded. If all these people had signed a petition or a
statement, you would have to take it seriously. It too would be valid
scientific evidence, albeit secondary.
Many other considerations call into question the validity of
secondary evidence such as petitions by experts. For example:
1. Funding, and conflicts of interest. Are these people being paid to
find a problem? You should not ask plasma fusion scientists about cold fusion.
2. Academic politics, and suppression. Would these people lose their
jobs if they did not sign, and if they did not go along with the majority?
3. Wishful thinking (positive) and irrational fear of the new (negative).
4. Various other sources of bias.
These issues can also cloud research papers and experimental data
(primary evidence).
I do not know enough about climate studies to judge whether these are
a significant problem in that field or not.
- Jed
