intuition.
eapply comp_spec_symm.
eapply comp_spec_consequence; eauto.
Qed.

Theorem comp_spec_impl_eq :
forall (A B : Set){eqda : EqDec A}{eqdb : EqDec B}(c1 : Comp A)(c2 : Comp B),
forall x y,
comp_spec (fun a b => a = x <-> b = y) c1 c2 ->
evalDist c1 x == evalDist c2 y.