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Re: Just So stories and science



<If I am understanding you correctly, you are asking whether or not
establishing the validity of an hypothesis of, say, dinosaur systematics or
functional morphology, advances the important discussion that keeps paleo
(and all sciences) going or whether it stymies it.>

Your comments on what you thought I said are correct and valuable.  Ideas
should be tested continuously as new information and methods arise, even the
ideas so long accepted you tend not to look at them anymore.
My concern, in addition, was what happens when a hypothesis is carefully
formulated and then means of testing it effectively are found, and the
hypothesis passes.  You have proven the hypothesis plausible, and the tests
continue, as you say.
Though the hypothesis is plausible, speculate for a moment that you could
also develop a competing hypothesis which meets the available facts and
stands up to the best tests you can devise.
The fact that you have found two hypotheses that meet the available facts
and tests means that neither can be  preferred at that point.  How could you
choose?
Now, the second-hand quote from Gould and Lewontin is partly about the
possibility that someone devising a hypothesis might immediately look for an
adaptation explanation and ignore other possibilities; I'd add, even if the
adaptation explanation would prove no better than the alternative.
By not looking for alternative hypotheses, you have strengthened
artificially your first idea.  It's a sort of test you have not performed.
The other piece concerns logic.  I had a co-worker who would not just accept
an idea of mine, but would doggedly follow every step, including the logic.
He would make me think hard when he asked, 'Why isn't it just as logical to
think that...' or 'Why do you assume that...'.  To draw a logical conclusion
is one thing, to find the necessity of your conclusion is something else.
Just as an alternate hypothesis can affect whether my hypothesis can be
accepted, so a single place in my logic where another conclusion is possible
from the premises I have established weakens the force of  my argument.
If I share a bias toward a certain type explanation with everyone else I
have to persuade, then I'm going to have an easier time selling my
hypothesis.  Even so, I have to look for alternatives exhaustively.  I'm
wondering whether the data in some parts of our favorite subject are
sufficient to be unsuccessful finding plausible alternative hypotheses or
logical conclusions.

>From Pinker & Bloom:
<The key point that blunts the Gould and Lewontin critique of adaptationism
is that natural selection is the only scientific explanation of adaptive
complexity.>

Gould and Lewontin were criticizing a trend current at time of writing, and
also now according to Lewontin in the other essay I url'ed, that of
over-emphasizing optimization by selection, thus producing elaborate and
unproveable stories, and ignoring alternatives.  You quoted the more
balanced, I'd say better, view in your response.  Pinker & Bloom are arguing
here that in some specific cases, such as the eye, it is impossible to
consider other hypothetical solutions besides adaptation.  They go on to
list why alternatives are impossible.  In cases of adaptive complexity, they
argue that no alternative hypothesis can be found, so they are free to find
adaptation a best explanation.
I thought HP Rowe would be amused by the choice of example.
Part of their main argument is that language is another exception.
So, in both cases you were right.
The questions remain though, about whether we can successfully eliminate
plausible alternatives in dinosaur study, and whether exceptional situations
of adaptive complexity exist.
I'm looking forward to your comments.
Regards,
 Brian