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Philosophy

The Logic of Belief Revision and the AGM Framework

Quick fact

The AGM framework was introduced in a 1985 paper by Alchourrón, Gärdenfors, and Makinson, and it has become the standard model for belief revision in philosophy and artificial intelligence, even though it treats belief as a full set of propositions rather than degrees of confidence.

Why this is interesting

You are certain the Earth is flat, but then you see a ship disappear over the horizon—how should you rationally revise your belief? The answer is not merely adding the new fact; it involves a principled logic of change.