Definition:Finished Propositional Tableau

Definition
Let $$T$$ be a propositional tableau.

Then $$T$$ is finished if every branch of $$T$$ is either:
 * finished, or


 * finite and contradictory.

A confutation is always a finished tableau because every branch is finite and contradictory.

A finite finished tableau either has at least one finished branch or is a confutation.