Section TheoryOfSequentCalculus.
Context {L: Language}
{Gamma: Derivable L}
{minL: MinimumLanguage L}.

Lemma DeductionMP_DerivableAssu_DeductionWeaken_2_DeductionImpElim:
DeductionMP L Gamma ->
DerivableAssu L Gamma ->
DeductionWeaken L Gamma ->
DeductionImpElim L Gamma.