Several people suggested that we must first agree upon a definition of the supernatural. We could perhaps agree among ourselves that the supernatural encompasses things that aren't real or that have no evidence or are made up, like the world of Harry Potter or Tolkein or the Bible, but religious folks would never accept such a definition, and unless we're content just to talk among ourselves we need a definition that they accept, and that we ourselves accept. Is that even possible?
I think it would be best to just not use the word supernatural. We could just say that science deals with what we can observe. If it can be observed then science can deal with it. When Christians make claims about God or some aspect of religion like prophecy then instead of saying that science doesn't deal with the supernatural (whatever anyone thinks that is) we'd just ask for the evidence. And this is what we often do.
I find that both religious and scientific people make the same mistake when asking for evidence that something is true. The religious often ask for the one piece of evidence that proves evolution true, and scientific people here often ask for the one piece of evidence that proves Christianity true.
But complex theories, whether about God or science, rarely have that one piece of confirming evidence. Ask yourself what is the one piece of evidence that proves the sun is at the center of the solar system. And Tycho Brahe spent a lifetime gathering the evidence used by Kepler to derive the laws of planetary motion.
So just as we talk about evolution being proved by a consilience of evidence from diverse fields, so can the religious argue that God (or prophecy or whatever) is proved by a consilience of evidence gathered from many sources ranging from the Bible to apocrypha to archeology and so on. As obvious as the conclusion that there is no Christian God might seem to us, proving that all this evidence actually supports that conclusion and not its opposite is no simple task.
--Percy
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