Saved on this device

Follow your curiosity

What discovery has been shared with you?

FACTREE gives you something interesting to discover every day — and something worth talking about together.

Start with one fact. Explore it, go deeper, then follow whichever branch catches your imagination.

Choose subjects for a surprise

Exploring any topic

Begin your discovery

Your next discovery is one click away.

Choose one or more subjects above, or leave Any Topic selected and let curiosity decide.

Philosophy

The Logic of Belief Revision and the AGM Model

Quick fact

The AGM model, proposed in 1985, provides a set of rational postulates that any belief revision operation should satisfy, such as success (the new belief is always accepted) and consistency (the revised belief set must be logically consistent, unless the new belief itself is contradictory).

Why this is interesting

You’ve probably changed your mind about something you were once certain of. But what does it mean to change your beliefs rationally? How can we decide which old beliefs to keep and which to give up when new evidence arrives?