Be it evolution in general, micro-evolution or macro-evolution.
Let's start with Gervase's three points:
- It's a basic position that you hold about the nature of reality that's not provable - it's a faith position.
- It's something that you put your trust in, and live your life on the basis of.
- It's something you urge others to believe as the truth.
Perhaps the third applies to evolution, The other two are garbage.
Let's start with the first one. There's this nifty concept called falsifiability (sorry about the spelling). Something is falsifiable if it can be proven false.
Things that are unfalsifiable are not apt for rational discussion, since the truth value behind the proposition is unknowable.
Here's an example of something that's unfalsifiable: there is a supreme being that commands the whole universe, yet is not part of it, and can not be contacted.
Here's something that's not: random mutations get selected by the environment to prosper.
That is, because it can be proven false. If there were no mutations, it would be false. If exposing diferent breeds to environments causes no differential in survival rate, it is proven false.
Yes, this is the micro-evolution Gervase accepts. Macro-evolution simply extrapolates from this generally accepted theory into a larger one. Is it the right one? Not sure.
There is no imaginable experiment that can prove the inexistence of god. That's why god's existence is a religious matter, and not a scientific one. The existence of microevolution can be seen, and even experimented (ask any guy that happens to have a few hundred fruit flies in a bottle).
As for macroevolution, well, as mpyne says, there is a thnkable experiment. And even if it isn't technically feasible, there can be a rational discussion, regarding the recombination sppeds, and radiation levels producing mutations, and volumes, and timescales.
So, discussing it is a rational process.
As for the second point: I doubt anyone lives his life based on evolution, although it can provide some reasonable tips about how to expect things to happen, but that's mostly reasoning by analogy.
Now religion.. one of its purposes is usually to describe how you should live.
So, what Gervase is describing is religion. And by his definition, evolution ain't.
Evolution theory may be wrong. That's ok. It happens to almost all theories in one way or another, usually they end replaced by a slightly evolved new version.
But religion? Well, dude, that's just another name for who the hell knows. If you accept religion as a premise, you are into voodoo land.
Maybe the universe only exists since 1987, and everything earlier is a thought in god's mind. Who knows? Presummably only him.
Maybe he's cranky and we all die and go to hell tomorrow. He's many things but not reasonable, as evidenced by his alleged handywork.
So, what's the point in arguing a subject where no rational discourse is appropiate, a subject which is the very basis of irrational discourse?
I have no idea. That's why I'm an agnostic.