A Theory of Hierarchical Consequence and Conditionals

We introduce A-ranked preferential structures and combine them with an accessibility relation. A-ranked preferential structures are intermediate between simple preferential structures and ranked structures. The additional accessibilty relation allows us to consider only parts of the overall Aranked structure. This framework allows us to formalize contrary to duty obligations, and other pictures where we have a hierarchy of situations, and maybe not all are accessible to all possible worlds. Representation results are proved. Contents

• Type: Journal
• Year: 2010
• Where: JOLLI
• Authors: Dov M. Gabbay, Karl Schlechta
• Keywords: A-ranked Preferential Structures, JOLLI 2010, Preferential Structures, Simple Preferential Structures