Merging Frameworks for Interaction
Johan van Benthem, Jelle Gerbrandy, Tomohiro Hoshi, Eric Pacuit

Abstract:
We define new dynamic epistemic models with an added notion
of 'protocol' describing the current informational process,
which may reflect conversation, observation, or experiment.
This adds a new concept of 'procedural information' to 
the factual and multi-agent information already handled
by dynamic epistemic logics. We show how this richer
perspective modifies existing representation results 
for DEL models inside branching temporal universes, and 
we give a new completeness proof for public announcement
logic with protocols, which no longer works via the
usual reduction to pure epistemic statements. Finally,
we sketch the contours of a general logic of protocols.
This is the expanded version of an earlier paper 
presented at TARK 2007, which includes a new notion
of 'local' world-dependent protocols that need not
be common knowledge between all agents involved.