  Allowing for the change in terminology over the centuries, Butler’s description can be read as a verbal explication of the categorical form of the Bayesian argument. If the facts can be accounted for without difficulty on the supposition of \(M\) but not, without great implausibility, on the assumption of \({\sim}M\), then they provide significant evidence in favor of \(M\). On this reading, Butler is tacitly assuming that the prior probability of \(M\) is not so low as to overcome the cumulative force of the evidence in its favor.