proposition: Lemma axAXT : prv (AX (fF ---> fF)).
proof: Proof. apply: rNec. exact: axI. Qed.
imports: mathcomp.ssreflect.ssreflect mathcomp(all_ssreflect) CompDecModal.libs(edone bcase fset base modular_hilbert) CompDecModal.CTL(CTL_def hilbert)