Relevance in belief revision

The dynamics of relevance: adaptive belief revision

This paper presents eight (previously unpublished) adaptive logics for belief revision, each of which define a belief revision operation in the sense of the AGM framework. All these revision operations are shown to satisfy the six basic AGM postulates for belief revision, and Parikh’s axiom of Relevance. Using one of these logics as an example, we show how their proof theory gives a more dynami...

Distance Semantics for Relevance-Sensitive Belief Revision

Possible-world semantics are provided for Parikh’s relevance-sensitive model for belief revision. Having Grove’s system-of-spheres construction as a base, we consider additional constraints on measuring distance between possible worlds, and we prove that, in the presence of the AGM postulates, these constraints characterize precisely Parikh’s axiom (P). These additional constraints essentially ...

Distance Semantics for Relevance-Sensitive Belief Revision Extended Abstract

The AGM postulates [4], [1] are widely regarded to have captured much of what is involved in the process of rational belief revision. Recently however, Parikh [7] observed that despite their success, the AGM postulates are rather liberal in their treatment of the notion of relevance. More precisely, Parikh argues that during belief revision a rational agent does not change her entire belief cor...

Belief Revision

Philippa, a Greek nineteen year old student at Patras University, has just discovered that Nikos and Angela are not her true parents; she was adopted when she was six months old from an orphanage in Sao Paulo. The news really shook Philippa. Much of what she used to believe all her life about herself and her family was wrong. After recovering from the initial shock she started putting her thoug...

Belief Revision