Section DerivableRules_multi_impp.
Context {L: Language}
{minL: MinimunLanguage L}
{Gamma: ProofTheory L}
{minAX: MinimunAxiomatization L Gamma}.

Lemma provable_add_multi_imp_left_head: forall xs1 xs2 y, |-- multi_imp xs2 y --> multi_imp (xs1 ++ xs2) y.