My focus of research is the area of Belief Revision (Logic of Theory Change): BR theory studies the impact of acquiring new information. It is a fundamental activity of human intelligence, and it defines an exciting and significant research area in philosophy, logic and computer science. Belief revision theory provides sound modellings for changes of beliefs in response to new information.
In the logic of theory change, the AGM model has acquired the status of standard model (Alchourrón, Gardenfors, and Makinson 1985). The AGM model aims to characterize the dynamics of beliefs of a rational agent. A change consists in adding or removing a sentence from a set of beliefs to obtain a new set of beliefs. This change obeys the following principles: 1. Primacy of new information: the new information is always accepted. 2. Coherence: the new set of beliefs has to be logically consistent. 3. Minimal change: a minimal loss of information contained in the previous beliefs, that is it attempts at retaining as much of the old beliefs as possible. Even though the AGM model is considered a standard model, it seems to be inadequate in many contexts. Consequently, in the last 30 years extensions and generalizations of AGM has been proposed (Fermé and Hansson 2011).