Friday, March 21, 20144:15 pmLogic and Games SeminarRoom 3305, CUNY Graduate Center

# Topologic: old and new results

## Konstantinos Georgatos

### John Jay College Of Criminal Justice

In 1992, Moss and Parikh introduced Toplogic an epistemic modal logic whose semanticas are based on subsets. Since then, research on this logic and it many extensions has been going strong. I will survey most of these results in the first part of this talk. On the second part, I will present how topologic can form a basis for the formalization of belief change operators, such as update, conditionals and contraction. Arbitrary nestings and iterations of such operators are easily automatized which is not the case in other studies of belief change in object language.