Reading a post at NeuroLogica that ended up reminding me of a woo straw man. I may want to figure out a short phrase for it to give it the Doggerel treatment: A lot of woos think that we dismiss the supernatural a priori because we're naturalists, materialists, etcetera, and it's supernatural or non-material or whatever.
There are two general, very different reasons we dismiss the supernatural. The first is short and sweet: Anything that has an effect on the world is natural. By definition. That leaves the supernatural with only stuff that doesn't affect anything, which isn't much different from nothing at all.
The second is still open to debate in the way that gravity's still open to debate: It's all about the evidence, and new evidence could overturn what we know. There's no a priori dismissal there, just extraordinary demands for extraordinary claims. And the woos generally don't live up to fairly ordinary scientific demands. Alties try to say their treatments aren't subject to double-blind control studies, psychics try to say their powers become unreliable when tested, and perpetual motion advocates have convenient malfunctions when showtime comes around.
We'll believe it when we see the good evidence. As for what that'll do for our philosophy: Not much. Discovering psychic powers for will fall into the same category as the verification of dark matter... only maybe a bit cooler because a lot of us are comic book geeks and we'd like the chance to put on an outlandish costume for something other than a convention. The "supernatural" is a category that shrinks as we understand more. Naturalism expands with every new discovery because it's inherently expansive in its definition.