>Bill Hamilton provides an interesting probability argument:
>
>> When events are not repeatible, we can still use science to learn about
>> them by studying multiple lines of evidence. The point that creationists
>> seem to ignore (or not respond to or it goes over their heads or...) is
>> that multiple lines of evidence support the current theory of evolution.
>> Dan Ashlock, one of the talk.origins regulars put it this way once, (loose
>> paraphrase) "There are about 100 lines of independent evidence that support
>> the currently accepted theory of evolution. Even if 95 of them were
>> totally bogus, the probability that the theory is correct is still 1 -
>> 2^(-5) = about 97 percent."
>
>Held at arms length, this argument appears very impressive. There are,
>>however, some implicit assumptions that warrant closer investigation. The
>>calculations assume that all lines of evidence are independent of each other
Yes. And that assumption was stated.
>and it assumes equal
>a-priori probability that each line of evidence is true or false (p=0.5).
Yes. And I forgot to mention that one. Whether Dan did or not, I don't
remember. I could go look up what he said, but you decided to let it
pass...
It's a fairly typical assumption when people are dealing with probabilities
in a very gross, imprecise way. No one should take my argument as being an
assertion that the evidence for evolution is overwhelming. Mainly I was
trying to point out what creationists frequently ignore in their criticisms
of historical science: That conclusions are reached by examining multiple
lines of evidence.
Each confirming line of evidence increases our confidence in the claimed
hypothesis. It doesn't of course prove it. Absolute proof is hard to come
by in the sciences.
>I would,
>for the sake of good science, challenge both these assumptions, but for the
>>moment, we let them stand.
Whew! :-).
>What is more important is that it is claimed that the theory of
>evolution is supported by 100 *potentially confirming* testable hypotheses.
>On the other hand, if it were possible to test the theory of evolution by
>constructing 100 *potentially falsifying* hypotheses, then even if the theory
>successfully PASSES 95 of them, using the same a-priori assumptions as before,
>the probability of the theory being correct is only about 3%.
Of course. However, Dan was claiming that the 100 lines of confirming
evidence exist. It would also be relatively easy to get him to volunteer
the view that creationists have not provided one single testable hypothesis
against evolution which has been established. The talk.origins archives
are full of attempted falsifying hypotheses, alleged supporting data and
refutations. This of course doesn't mean no such hypothesis is possible,
but finding them is apparently a problem...
Of course neither
>of these calculations have much bearing on reality, but they draw attention to
>an important fact: The theory of evolution, as it is currently framed, whether
>by intent or by circumstance, is not falsifyable.
You can also find in the talk.origins archives examples of findings that
would falsify evolution. One of them is a modern human fossil more than
(something like ) 1.5 million years old.
>This is what lead science
>philosopher Karl Popper to criticize the theory of evolution in the same way
>he challenged other theories in vogue, such as Marxist economics and Freudian
>psychology. To Popper, the most impressive scientific theories were those that
>could be subjected to daring, potentially falsifying experiments, like
>Einsteins
>theory of relativity. In stead, what Karl Popper found were investigators
>intent
>only on seeking evidence to *confirm* the theory. One may wish to argue that
>falsifying experiments DO exists, but only after surrendering the above
>probability estimates.
>
No. Provide them now and let some of the experts in this group tackle them.
Bill Hamilton | Vehicle Systems Research
GM R&D Center | Warren, MI 48090-9055
810 986 1474 (voice) | 810 986 3003 (FAX)
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