Miracles, Hinges, and Grammar in Wittgenstein's on Certainty

In §513 of ON CERTAINTY Wittgenstein asks "What if something really unherad-of happened?" But whit this question he is not asking us to make a forecast, a prediction, or some sort of empirico-psychological prophecy about our possible reactions. As I will attempt to show, the question regarding the unheard-of is part of Wittgenstein's philosophical method - which is to say, it is one of the instruments with which he combats what he sees as the principal source of the confusions in philosophy: mistaking the grammatical for the empirical or, as he also says, the conceptual for the factual. In this sense the question regarding the unheard-of can shed some light on the grammatical status of what he calls "hinges"