Common knowledge in update logics

Current dynamic epistemic logics often become cumbersome and opaque when common knowledge is added for groups of agents. Still, postconditions regarding common knowledge express the essence of what communication achieves. We present some methods that yield so-called reduction axioms for common knowledge. We investigate the expressive power of public announcement logic with relativized common knowledge, and present reduction axioms that give a detailed account of the dynamics of common knowledge in some major communication types.

• Type: Conference
• Year: 2005
• Where: TARK
• Authors: Johan van Benthem, Jan van Eijck, Barteld P. Kooi
• Keywords: Common Knowledge, Reduction Axioms, So-called Reduction Axioms, TARK 2005