 The worry is that a person can meet this demand only by luck or with an unrealistic ability—the ability to demarcate all logical truths from the other propositions. But some Bayesians argue that the standard version of Probabilism can be suitably de-idealized to obtain a weak version that does not imply Strong Normalization. For example, the extensibility version of Probabilism (discussed in  section 3.1)  permits one to have credence gaps and, thus, have no credence in any logical truth (de Finetti 1970 [1974]; Jeffrey 1983; Zynda 1996). Indeed, the extensibility version of Probabilism only implies: