Iain Murray, in his comment on the fact that the Supremes are not going to review the latest "teaching evolution" case, says:

...the idea that "evolution is just a theory" is quite simply wrong. The fact of evolution has been established beyond reasonable doubt. It is how evolution works that is in question. From this report, it appears that the science teacher questions even the fact.

While I think that I know what he means, this isn't really the case. Evolution is (in fact) a theory, though it's not "just" a theory. To say something is "just" a theory is to denigrate the very notion of theories, which are part of the fundamental basis of the scientific method.

Evolution is "just" a theory. As are Newton's Laws. As are both Special and General Relativity. As are all scientific principles.

We cannot prove any of them to be correct--theories can only be falsified. What we can do is lay out a set of criteria by which we judge the validity of scientific theories, and determine to what degree they are satisfied by particular theories. Those that satisfy the criteria best become the most accepted theories. Evolution, in broad terms (though the details are still problematic), does provide the current best available explanation for the diversity of life and the fossil record, within the confines of science.

These last words are key. The problem with teaching creationism as a substitute for evolution is not that it isn't true--there's no way to know that. It's that it isn't science. In a science class, what should be taught is science and the scientific method. Whether or not this represents the "truth," or the most reliable means of achieving knowledge is unknown, unknowable, and irrelevant.

The scientific method and logic are the means chosen by people of reason to gain knowledge, at least in those spheres for which such means are applicable. The acceptance of them, like the acceptance of Biblical or other forms of divine revelation, must ultimately be taken on faith. This is disconcerting to scientists, but it's true nonetheless.

Articles of faith for those of reason (like myself) are:

• There is an objective reality

• This reality is not affected simply by the beliefs of others

• Its nature can be determined, ultimately, by forming falsifiable theories about it, and asking questions of it in the form of experiments

There may be others, but these are clearly axioms of the scientific-minded, and they cannot be proven, even to someone who accepts logic and proofs as a means of achieving knowledge. For those whose chosen method of gaining knowlege is divine revelation, there is no effective argument.

So there is some truth to the claims of the devout that "secular humanism" is a religion, which to me, merely means that if we don't want to indoctrinate children in public schools, there is no solution except to abolish public schools (perhaps replacing them with vouchers, if we believe that education should be publicly funded), because "everyone's gotta believe in somethin'."

[Update]

After an email exchange with Iain, he puts the following on his web site, from another website:

Just as much as gravitation is a fact, is so evolution.

I agree that evolution is as much of a fact as gravitation. The problem, is, as I state above, that neither is a "fact." Gravitation is a theory. I fear that this website is obscuring terminology in an attempt to convey a (valid) concept--that evolution is as well-founded as any other scientific theory. Such sloppiness does nothing to advance the cause of science in general, or evolution in particular.

Here is an example.

Fact: When I drop an object, it falls toward the center of the earth with an acceleration of approximately 32 feet per second per second.

Theory: This happens because two masses attract each other in proportion to their product, and in inverse proportion to the square of the distance between them.

The second is what we call "gravitation." The first is a fact, but it's not gravitation--it's simply a phenomenon that we explain with gravitation (and which could be explained with other theories, but not as well, by scientific criteria).

Similarly, the available fossil record and existing inventory of flora and fauna is a fact (or to be more precise, a compendium of facts). That they evolved into the present state via natural selection is a theory that explains those facts.

Really, folks, there's nothing wrong with theories. Despite the attempt of creationists to use them to damn evolution, they are the stuff that all science is made of.

Hail and well met, fellow Karl Popper fetishists! hahahaha

Very good response to Iain. An interesting extension of your gravitational example is the current problems being encountered in trying to measure the Gravitational constant which actually relates how much two masses attract each other. Apparently trying to get very many digits of accuracy in this measurement is extremely difficult as the measuring devices aren't massless and have a disturbing effect on that measuring process. So even an accurate estimate of exactly what gravity is doing, which has huge astronomical implications, is very hard to obtain. This would imply that the Newtonian model is only a first order model and there may be higher order effects, somewhat akin to the issues attending on Darwin's theory, which simply are impossible to quantify or even to prove or disprove.

Well, we already know that Newton is only first order--Einstein proved that.

But my point goes beyond that--my point is that all such models, no matter how refined, are only that--models, and we can never say that they are reality or "facts"--they are just a representation of it.

I'm in the "working theory" camp. I got to look at the Creation Science books in the late '80s at the local Baptist school; not much science beyond "God did it". There's a growing "intelligent design" movement amongst some serious biologists. I haven't studied it too seriously, but what I?ve seen falls closer to a defendable idea; that our biology is too complex to have happened just by luck, someone (e.g. God) had to have planned it out.

Theistic evolution is something Catholics and liberal Protestants can swallow, but for a (hopefully) good evangelical like myself, you then have to read the first part of Genesis a bit weirdly. Adam and Eve were a separate lab experiment of putting people in a perfect spot and yet they turned away from God. Noah was part of regional not worldwide flood (Black Sea undersea archeology gives some support here). Genesis is Adam & Eve>Fast forward to Noah>Fast forward to Abram/Abraham. From Abraham on the Bible is largely backed up by history and archeology; it's at least an non-anachronistic period piece, it?s Adam and Noah that the evangelical intellectual has to reconcile.

Figuring out how God did it's the question, since I'm not buying the dumb luck option. I'm open to creation being in six eras rather than literal days; the Genesis account tracks the evolutionary account surprisingly well when you allow that it was a theology rather than biology text.

When we get to heaven, I'll be sure to ask Him how He did it, but in the meantime, I?ll have to continue to figure it out for myself

Well, the "dumb luck" comment is a strawman, and betrays a lack of understanding of the theory. Natural selection is not about dumb luck, it's about luck directed by success. Those things that are successful thrive, by definition, and those that aren't don't. So eventually, "lucky" things dominate. This is just the power of large numbers and long time scales.

You're entitled to believe whatever theory you wish (and your version may even be the one that's ultimately "true"), but any form of "God did it" is not science--it's a cop out, and simply begs the question.

If you're going to believe in intelligent design, then you have to come up with a *testable* theory about the designer, and his or her origin. Otherwise, you're engaging in theology, not science.

And by the time your testing is done you'll be dead. This is why most scientific discussion of evolution rapidly transmogrifies into philosophical diatribes.