Talk:Sequent calculus

Quantifiers

The presentation does not seem to be completely uniform concerning quantifiers: are first-order quantifiers taken into account? It would be nice.

A few related points:

• Why a distinction between atomic formulas and propositional variables?
• Some mixing between $\forall x A$ and $\forall X A$. I tried to propose a convention on that point, but it does not match here with the use of α for atoms.
• Define immediate subformula of $\forall X A$ as A?

-- Olivier Laurent 18:37, 14 January 2009 (UTC)