If a supernatural event occurred, how would you tell?

[Angrboda]

The hallmark of the natural is repeatability. Natural refers to natural law, to regularities in the world that can be demonstrated. Even if gravity were a chance movement of matter that always coincidentally lined up with our mathematical equations, it would still be deemed a natural law. Natural law isn't about a metaphysical underlying cause or essence, it's about predictability and conformance to mathematical model. As such, the supernatural is rightly excluded from science, not by some metaphysical bar excluding it, but because science studies natural law, which implies repeatability; supernatural events, their causes, aren't repeatable, aren't regular enough to be modeled. If one sort of "supernatural" events do become repeatable, predictable and capable of being model, it ceases to be supernatural and becomes just one more example of nature and natural law.

Oh, and regarding the "unnatural" terminology, I come down against its use. There is nothing in existence, aside from the supernatural, that is not natural. The works of termites, beavers, and men are just an example of a very long and complex chain of natural processes. But nowhere along that chain did the processes stop being natural and start being something else. This question comes up also in the subject of intelligent design. People like William Dembski have argued that "designed things" have certain properties that undesigned things do not. In the language of Paley, things just "look designed." The question there is analogous. What would it mean for something to "look designed" - if there can even be such? The same question applies to termites, beavers and humans - what part of their activity is "unnatural" ? Is defecating a natural act and watchmaking an unnatural one because they employ different organs in producing the output? Surely if this natural versus unnatural split is to have any validity, you'll need a divining rod which jerks appropriately at the unnatural, but not at the natural. What is that divining rod, what is the test?