English
There is a canonical way to recover a MonObj from its representation by a presheaf: the representable by X correspondences yield a MonObj X.
Русский
Существует каноничный способ восстанавливать MonObj из представления предкатегории: соответствия представимого X приводят к MonObj X.
LaTeX
$$$\\text{ofRepresentableBy}$ yields X from its representable by$$
Lean4
/-- If `M` is a monoid object, then `Hom(-, M)` as a presheaf of monoids is represented by `M`. -/
def yonedaMonObjRepresentableBy : (yonedaMonObj M ⋙ forget _).RepresentableBy M :=
Functor.representableByEquiv.symm (.refl _)