intros.
inversion H.
trivial.
Qed.

(* Specifications: *)
(** If (M,N) is in S(h) and N is a name then (M,N) is in h *)
Theorem nam_right_syn :
forall (h : hedge) (M : Msg) (b : Nam),
synthesis h M (MNam b) -> h M (MNam b).
(** h is included in S(h) *)
Lemma h_incl_syn : forall h : hedge, inclusion h (synthesis h).
unfold inclusion in |- *.