The propositional account of explicit and implicit knowledge interprets cognitive differences between direct and indirect test performance as emerging from the elements in different hierarchical levels of the propositional representation that have been made explicit. The hierarchical nature of explicitness is challenged, however, on the basis of neuropsychological dissociations between direct and indirect tests of memory, as well as the stochastic independence that has been observed between these two types of tests. Furthermore, format specificity on indirect test of memory challenges the basic notion of a propositional theory of implicit and explicit knowledge.