According to Dietrich quiddity is properly defined as the formal determination of a being, giving it its specific intrinsic character by means of which it can also be known. Strictly speaking, therefore, quiddity is found only in composite beings since it implies a formal aspect of a being. Unlike Aquinas Dietrich will not allow quiddity to designate the whole composite, even if the designation is understood to be abstract. Strictly speaking, therefore, quiddity is not applied to simple beings.