Definition:Finished Branch of Propositional Tableau

Let $$T$$ be a propositional tableau.

Let $$\Gamma$$ be a branch of $$T$$.

Then $$\Gamma$$ is finished if:


 * $$\Gamma$$ is not contradictory, and


 * Every non-basic WFF on $$\Gamma$$ is used at some node of $$\Gamma$$.

That is, $$\Gamma$$ is finished iff the set $$\Delta$$ of propositional WFFs which occur along $$\Gamma$$ is a finished set‎.