Projective Default Epistemology

摘要

We show how to extract iterated revision strategies for complex evidence, e.g. epistemic conditionals, from reasonable default inference notions. This approach allows a more extensive cross-fertilization between default reasoning and belief revision. To illustrate it, we use powerful default formalisms exploiting canonical ranking constructions, like system JZ, for specifying new ranking-based revision mechanisms. They extend Spohns ranking revision to sets of conditionals and satisfy basic rationality principles.