=== === ===
"Whoa, hold on there. You're both right!" :-)
... New 'Darwinism' is BOTH a testable scientific theory
AND a metaphysical world-view!
(*) With apologies to readers who are
unfamiliar with that classic
_Saturday_Night_Live_ commerical parody.
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Actually, depending on its context, I have seen "Darwinism" fall into at
least THREE categories: testable scientific theory, untestable research
program/paradigm, and metaphysical world-view.
1) Here's an example of a testable prediction from modern Darwinism:
Species within the same family/order should show a high degree of homology
in their genes. Nearly every functional gene in one species should have a
corresponding functional gene in the other species, performing a similar
task. Moreover, there should be a mutational pathway, which does not
diverge too much from straightforward parsimony reconstruction, in which
every gene along the pathway codes for properly functioning products.
(This type of testing is possible with our current technology, and is
already being done for a few genes in a few labs.)
This prediction could be extended from the family/order level to class and
phylla. It could also be extended from the level of genes to the entire
genome. (These extensions are a bit beyond current technology.)
2) In MOST contexts, I'd say that the modern synthesis of genetics and
Darwin's theories falls into the category of "research program/paradigm."
When unexpected data is found, the central core of the theory is
maintained, but auxilliary hypotheses are formed to fit the data into the
general theory. (e.g. Natural selection is augmented with sexual
selection; mechanisms for gene transfer between species are proposed.)
Some of those auxilliary hypotheses are _ad_hoc,_ but many of them are
"progressive" in the sense that they increase the empirical content of the
overall theory and make testable predictions. Darwinists' knack for
creating new auxilliary hypotheses is frustrating to people who want to
replace the entire paradigm, but it is nevertheless a proper practice of
science. All fields and subfields of science have their "central core"
theories which are only rarely replaced.
3) Clearly, Darwinism is at the center of a Naturalistic world-view for
many people, including many scientists. No need to repeat all the
examples here. Since so few scientists have studied the philosophy of
science, most scientists are unaware (or only vaguely aware) of the proper
distinction between the second and third categories.
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What about Popper's "recantation"? Well, most scientists, most of the
time, unconsciously use SECOND category for "Darwinism/evolution/natural
selection." But when Popper described it as "unfalsifiable," he did not
yet have the categories of "paradigm" and "research program" available to
him. (**) Those categories were later contributions of other philosophers
of science. The language of Popper's "recantation" suggests to me that,
over the intervening years, he had become aware of that category and its
role in scientific thinking.
(**) Someone please correct me if I have the chronology wrong.
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---"Mmmm. Tastes great."
"... And just look at that shine!"
Loren Haarsma