Definition all_assertions_computable  :=
forall (Espec: OracleKind) psi tx vx (Q: assert),
exists k,  assert_safe Espec psi tx vx k = Q.
(* This is not generally true, but could be made true by adding an "assert" operator to the programming language *)

Lemma assert_safe_last:
forall {Espec: OracleKind} ge ve te st rho w,
(forall w', age w w' -> assert_safe Espec ge ve te st rho w) ->
assert_safe Espec ge ve te st rho w.