∀ {R S T : CommRingCat} (f : R ⟶ S) (g : S ⟶ T),
  CategoryTheory.CategoryStruct.comp (AlgebraicGeometry.Spec.map g) (AlgebraicGeometry.Spec.map f) =
    AlgebraicGeometry.Spec.map (CategoryTheory.CategoryStruct.comp f g)