(** [(A->B) \/ (B->A)] is equivalent to [(C -> A\/B) -> (C->A) \/ (C->B)]
    (proof from [[Dummett59]]) *)

Definition RightDistributivityImplicationOverDisjunction :=
  forall A B C:Prop, (C -> A\/B) -> (C->A) \/ (C->B).

Lemma weak_excluded_middle_iff_classical_de_morgan_law : weak_excluded_middle <-> classical_de_morgan_law.