De Re Updates
This work addresses a foundational issue in formal epistemology and AI for researchers in logic and knowledge representation, though it appears incremental as it builds on prior work by Wang and Seligman.
The paper tackles the problem of distinguishing between de dicto and de re updates in dynamic epistemic logic by proposing a lightweight logic based on a dynamified epistemic language with assignment operators. It achieves complete axiomatizations for counterparts of public announcement logic and event-model-based DEL using new reduction axioms.
In this paper, we propose a lightweight yet powerful dynamic epistemic logic that captures not only the distinction between de dicto and de re knowledge but also the distinction between de dicto and de re updates. The logic is based on the dynamified version of an epistemic language extended with the assignment operator borrowed from dynamic logic, following the work of Wang and Seligman (Proc. AiML 2018). We obtain complete axiomatizations for the counterparts of public announcement logic and event-model-based DEL based on new reduction axioms taking care of the interactions between dynamics and assignments.