Date: Friday, 19 April 2013
Room ‘leslokaal 2’, basement, Blandijnberg 2
B-9000 Ghent, Belgium
In this talk I will present a way to evaluate the truth-tracking
properties of various belief-revision policies. I will use formal
learning theory (Gold, 1967), and the semantic approach to knowledge and belief originating in dynamic epistemic logic (Baltag et al., 1998; Van
Benthem, 2007). I will argue that truth-tracking can be analyzed in
terms of identifiability in the limit, and that it relies on topological
separability properties of belief states.
The results concern mostly the conditions for universality of a belief
revision policy (i.e., a belief revision method being as powerful as
full identification in the limit). This leads to identifying factors
that influence the (non-)universality of a belief-revision policy: the
prior conditions for belief revision (e.g., standard belief-revision
models); type of incoming information (e.g., entirely truthful as
opposed to partially erroneous); properties of belief-revision-based
learning functions (e.g., conservatism). In this framework we can
naturally treat the procedural aspect of iterated belief revision,
address some intermediate stages of such iterations and relate them to
the ultimate success of a belief-revision policy.
The results presented in this talk come from a joint work with Alexandru
Baltag and Sonja Smets (Baltag et al., 2011).
dr. Giuseppe Primiero Centre for Logic and Philosophy of Science Ghent