-lemma lpr_fpb (h) (G) (T): ∀L1,L2. ⦃G, L1⦄ ⊢ ➡[h] L2 → (L1 ≛[T] L2 → ⊥) →
- ⦃G, L1, T⦄ ≻[h] ⦃G, L2, T⦄.
-/3 width=1 by fpb_lpx, lpr_fwd_lpx/ qed.
+lemma rpx_fpb (G) (T):
+ ∀L1,L2. ❨G,L1❩ ⊢ ⬈[T] L2 → ❨G,L1,T❩ ≽ ❨G,L2,T❩.
+/2 width=5 by fpb_intro/ qed.
+
+(* Basic inversion lemmas ***************************************************)
+
+lemma fpb_inv_gen (G1) (L1) (T1) (G2) (L2) (T2):
+ ❨G1,L1,T1❩ ≽ ❨G2,L2,T2❩ →
+ ∃∃L,T. ❨G1,L1,T1❩ ⬂⸮ ❨G2,L,T❩ & ❨G2,L❩ ⊢ T ⬈ T2 & ❨G2,L❩ ⊢ ⬈[T] L2.
+// qed-.
+
+(* Basic_2A1: removed theorems 2:
+ fpbq_fpbqa fpbqa_inv_fpbq
+*)