archetypal fool

Ok, Taltos, I see what you're saying, but you can't necessarily "prove" a scientific theory. The only thing above a scientific theory is a scientific law, and these are usually presented mathematically. You can't prove the theory of evolution mathematically, because we aren't dealing with energy or motion or some otherwise measurable variable.

Take, for example, the Theory of Gravity and the Law of Gravity. The Law of Gravity is a mathematical proof, while the Theory of Gravity is an attempt explain what exactly gravity is and where it originates from. The fact that it's a theory doesn't hurt its existence because, here we are, held onto our planet, which revolves around the sun, which is one of billions of solar systems revolving around a super-massive black hole.

That being said, you can't "dis-prove" a theory either. If you can find contradictory information, then the theory is amended; the theory of evolution has been amended many times for just that reason, but always in the face of verifiable fact and observations.

The term "theory" doesn't hold the same meaning in science as it does colloquially. A scientific theory is as close to fact as you can get when describing complex (as in, not obvious or quick) natural phenomena. Evolution is a fact, and this can be seen in both microorganisms and complex organisms (for example, the Kaibab Squirrel). However, there is still scientific debate as to some of the mechanics of evolution; and then you have your gaps in the fossil record (however, you can't really hold these gaps as proof against evolution, for obvious reasons).

And scientists aren't content with saying "it just happens." I can see where this misconception arises in regards to the Big Bang Theory, but there are other theories (though thy're mostly mathematical), specifically involving String Theory and M Theory and so on, but no scientist will ever answer a question with "it just happens", and we're always looking to explain these things.

No one is shutting off intelligent design, but in scientific terms, it is not a theory on par with evolution, because it has no evidence for it. As soon as some shows up, then there will be some credence, but until then, it's a hypothesis and nothing more. Law > Theory > hypothesis > observation. That's the way things work., and they've been working fine so far, free from ideological obstruction, so we can't just start letting religious stories into the science books.

EDIT: I'm not sure how effective my post was in clearing up the misconceptions about "theory" so I'll add the following:

In common usage, the word theory has the same meaning as the scientific meaning of a hypothesis. For example, if a plane randomly explodes during flight, the television news reporters might say something to the effect of: "One theory is that the a spark set off inside the fuel compartment caused the explosion; another is that there was a bomb; another theory is that there was an explosive mechanical failure." This use of "theory" is analogous to the scientific meaning of hypothesis.

Once the actual cause of the explosion is found, then the news might say "it's verified that a mechanical failure caused the explosion because of so-and-so," or "it's proved that a mechanical failure caused the failure because of so-and-so," then this use of "verified" or "proved" is analogous to the scientific meaning of "theory".

I hope that helped.*

*This illustration was taken from "Physical Geology: Earth Revealed" by Carlson, Plummer and McGeary.

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