full-meet-revision-satisfies-all-agm-postulates

IN premise — summaries/2026/08/24/wiki-Belief_revision.md

Created 2026-08-24T17:11:07+00:00

Full meet revision is defined as K * P = K + P when K + P is consistent, and K * P = Cn({P}) when K + P is inconsistent, and it satisfies all 8 AGM postulates but is considered 'too conservative' because it discards all old information upon inconsistency.

Summary

Full meet revision is a rule for updating the system's knowledge when new information arrives: if it fits with what is already stored, it simply gets added, but if it conflicts, every prior piece of information is thrown out and only the new input is kept. It is formally correct by all the standard rules, but it is a blunt instrument, treating any contradiction as an all-or-nothing situation rather than trying to salvage the parts of the old knowledge that still make sense.