 It has been argued that one of the limitations of Bayesianism is that it is fatally committed to the (clearly false) null support thesis (Glymour 1980). The standard Bayesian condition by which evidence e supports h is given by the inequality \(p(h\mid e) \gt p(h)\). But where e is known (and thus \(p(e) = 1\)), we have \(p(h\mid e) = p(h)\). This came to be known as the ‘Bayesian problem of old evidence’. Howson (1984) noted that this problem could be overcome by selecting a probability function \(p^*\) based on the assumption that e was not known—thus even if \(p(h\mid e) = p(h)\), it could still hold that \({p^*}(h\mid e) \gt {p^*}(h)\). Thus followed an extensive literature on the old evidence problem which will not be summarized here (see, e.g., Christiansen 1999; Eells &amp; Fitelson 2000; Barnes 1999, 2008: Ch. 7; and Hartmann &amp; Fitelson 2015).