{A} `{HasEquivs A} {a b c : A} (e : a $<~> b) (f : b $-> c) (g : a $-> c) (p : f $o e $== g) : f $== g $o e^-1$. Proof. apply (cate_epic_equiv e). exact (p $@ (compose_hV_h _ _)^$). Defined.
Require Import Basics.Utf8 Basics.Overture Basics.Tactics Basics.Equivalences. Require Import WildCat.Core. Require Import WildCat.Opposite.