logic of belief

The "logic of belief," or belief revision, is a field within applied logic that examines how individuals update their beliefs when presented with new information. It's a crucial area for both epistemology (the study of knowledge) and artificial intelligence.1

In this theory, beliefs are represented as "belief sets," which are collections of statements logically derived from each other. When new information is introduced, a belief set can undergo expansion (adding new information), contraction (removing information), or revision (changing a belief from accepted to rejected or vice versa). The goal is to maintain logical consistency while making these changes, often considering the "entrenchment" or how strongly a belief is held. This process is non-monotonic, meaning new information can alter previous conclusions.1