crashfrog writes:
This also goes to discredit an idea you proposed earlier, that if a theory isn't the best theory, then it's unscientific.
Well, perhaps the theory isn't, but rejecting the better theory in favor of it certainly would be.
Which is a better theory can be a matter of opinion, it depends upon the specific circumstances. For example, say there are two theories attempting to explain five related phenomena, and which one explains each phenomena best differs like this:
Theory Factor A Factor B Factor C Factor D Factor E
==============================================================
Theory #1 X X X
Theory #2 X X X X
Even though Theory #2 explains more phenomena, it could still easily be debatable which theory is best, for any number of reasons. For instance, explaining some types of phenomena might be much more significant than others. But what about this case:
Theory Factor A Factor B Factor C Factor D Factor E
==============================================================
Theory #1
Theory #2 X X X X X
In this case it would be perverse to accept Theory #1 and reject Theory #2. This is analogous to the situation between Creationism and science. Evolution explains the fossil progression in the geologic column, flood theory does not. Geology explains how the geologic layers formed, flood theory does not. Geology explains why the proportion of daughter products of radiometric elements increases with depth, flood theory does not. Evolution explains the diversity of species, Creationism does not. Evolution is consistent with the long time frames of geology and cosmology, Creationism is not.
Any reasonable attempts at validation of scientific theory must include aggressively pursuing explanations of the evidence. Failing to explain portions of the evidence is an extremely significant fault. For example, despite string theory's stunning achievement of unifying gravity with the other three forces, its inability to produce sensible results for much particle behavior caused it to be rejected by the mainstream scientific community for the first 15 years of its life. It was rejected because failure to be consistent with the evidence is an extremely serious deficiency of the highest magnitude.
The premise of this thread, that evolution lacks empirical support, is simply ludicrous and doesn't merit discussion. But the discussion that has developed concerning how one legitimately identifies viable theory is an important one. Every individual has personal criteria, but acceptance of theory is an informal consensus process of many scientists. No human endeavor has unanimity, and Creationists often make much of legitimate scientists like Michael Behe and Halton Arp who buck the mainstream. That their ideas are not accepted by the mainstream doesn't mean they're wrong, but an objective assessment of the span of phenomena explained by their preferred theories (ID for Behe, questioning the expanding universe for Arp) reveals a large number of holes. Unlike the theories of fringe scientists like Behe and Arp, widely accepted theories explain more of the data than any other theory.
But that doesn't make Behe and Arp's theories unscientific (and in fact Behe has done no professional work in ID since he has never advocated ID in any of his technical papers, all of which are consistent with traditional theories within biology). In Arp's case, the small number of anomolies he's identified are dwarfed under mountains and mountains of evidence supporting mainstream views. The immense disparity in supporting evidence is why Arp's views are in the minority. But again, that doesn't make his views unscientific. Arp is in the middle of a legitimate scientific debate, albeit one he is losing badly.
Where does one cross the line from being scientific to no longer being scientific? That's a tough one. I think I could write quite a bit and still not give anyone, including myself, a clear idea of how to tell. Probably it's best to not even try to answer this question, but instead just to assess the validity of any proposal from a scientific perspective. Instead of dividing theories into the scientific and the unscientific, we coudl probably more profitably divide them into categories ranging from "massively supported by evidence" down to "little evidential support" and continuing on down to "contradicted by the evidence."
Evolution fits in the "massively supported by evidence" category, while Creationism fits in the "contradicted by the evidence" category. This is why Creationism has had to abandon scientific work and instead lobby school boards for representation in science class.
--Percy