String theory, from which I understand notions of the multi-verse are derived, would thus be a theory of the supernatural.
I guess my point is much the same as Taq's but I was going to say that if string theory is logically derived from evidence that exists in this universe then it wouldn't be supernatural even if it describes processes that don't happen in this universe. Othernatural perhaps. Just like geometry is not the same here on earth as it is elsewhere in our universe.
If the multiverse theory is correct then maybe our universe just got a lot bigger. Anything that can be known will be incorporated into the realm of the natural.
Ah I see that we are mostly in agreement. I would make this point though,
Is the existence of the universe an example of something like that?(something that defies explanation)
It depends doesn't it? If the universe was migically poofed into existence by an omniscient, omnipotent creator of all that is seen and unseen - Then yes the creation and existence of the universe would be an example of something like that.
Magic is the perception that something impossible has happened. It is not actually something happening that is impossible (obviously). I would say that supernatural is a concept that is equivalent to the concept of magic.