-lemma scpes_refl_O_O: ∀h,g,G,L,T,l. ⦃G, L⦄ ⊢ T ▪[h, g] l →
- ⦃G, L⦄ ⊢ T •*⬌*[h, g, 0, 0] T.
-/3 width=3 by scpds_refl, scpds_div/ qed.
-
-lemma scpes_sym: ∀h,g,G,L,T1,T2,l1,l2. ⦃G, L⦄ ⊢ T1 •*⬌*[h, g, l1, l2] T2 →
- ⦃G, L⦄ ⊢ T2 •*⬌*[h, g, l2, l1] T1.
-#h #g #G #L #T1 #T2 #L1 #l2 * /2 width=3 by scpds_div/
+lemma scpes_sym: ∀h,g,G,L,T1,T2,d1,d2. ⦃G, L⦄ ⊢ T1 •*⬌*[h, g, d1, d2] T2 →
+ ⦃G, L⦄ ⊢ T2 •*⬌*[h, g, d2, d1] T1.
+#h #g #G #L #T1 #T2 #L1 #d2 * /2 width=3 by scpds_div/