∀ {R : Type u_1} [inst : CommRing R],
  { obj := fun M => ModuleCat.of R ↑M.toModuleCat,
          map := fun {X Y} f => ModuleCat.ofHom (QuadraticModuleCat.Hom.toIsometry f).toLinearMap, map_id := ⋯,
          map_comp := ⋯ }.comp
      (CategoryTheory.forget (ModuleCat R)) =
    CategoryTheory.forget (QuadraticModuleCat R)