Speaker:     Egor Ianovski
Affiliation: The University of Auckland
Title:       Logics of belief change
Date:        Thursday, 9 Jun 2011
Time:        4:00 pm
Location:    Room 6115, Owen Glenn Building

We are at war with Eurasia. We have always been at war with Eurasia. Eastasia is our ally. How then, should we respond to an announcement of war with Eastasia? Is it enough to drop the belief that Eastasia is our ally, or do we need to revise our entire belief set?

What if the next day we are led to believe that we are at war with Eurasia again? Can we revert to our prior belief set, or has the first announcement changed our beliefs forever? If I have a friend that heard the same announcements, what can I conclude about their beliefs? Did they change the same way as mine or if not, for what reasons? In this talk we examine two main trends in the logical treatment of belief change, with focus on problems that arise with iteration and a multi-agent setting.

Note an unusual day of the week! Everyone welcome!