Section DerivableRulesFromSequentCalculus.
Context {L: Language}
{GammaD: Derivable L}
{bSC: BasicSequentCalculus L GammaD}.
Context {minL: MinimumLanguage L}
{minSC: MinimumSequentCalculus L GammaD}.

Theorem deduction_theorem_multi_imp:
forall (Phi: context) (xs: list expr) (y: expr),
Union _ Phi (fun x => In x xs) |-- y <->
Phi |-- multi_imp xs y.