«Impact» and «Overrule»: two models of belief-assesment in Hume's essay "Of Miracles"

The article seeks to explicate two models of belief-assessment that appear to be operative in Hume's essay Of Miracles and that correspond to the two parts of the striking phrase "mutual destruction". One, which we tag "Impact", treats the mutual interaction of bodies of evidence and testimony on the model of a collision between two physical objects, and seeks to calculate the resultant quantities. The other, which we tag "Overrule", operates on the quasi-judicial model of the inadmissibility of certain evidence as tainted by its provenance or by its intrinsic implausibility. The suggestion is made that the compresence of these two models may help understand why it is so hard to identify the basic argument of Hume's essay; the question is left open of whether or not Hume has, perhaps in addition to the two models presented, any decisive way of providing "an everlasting check to all kinds of superstitious delusion".