 The formal distinction in this context is fundamentally a way of distinguishing the necessary properties of a particular substance, in cases where the natures of which the substances are instantiations are not coextensive. Given this, what sort of relation “ties” these two formally distinct components together? Scotus suggests that this relation is real (i.e. numerical) sameness, a kind of unity falling short of absolute identity (Scotus, Ordinatio I, d. 2, p. 2, qq. 1–4, n. 403 (Scotus [OO], 2:356)). This sameness is presumably something rather like the relation of compresence found in Russell and others, though unlike compresence, real sameness is not only symmetrical but also transitive (see Tweedale [1999], 2:463–464). Scotus is able to claim transitivity for the relation of real sameness since, as we have seen, he believes that the common nature instantiated in two distinct particulars does not itself have real (i.e. numerical) identity (see Tweedale [1999], 488). The haeeceity and the nature in the particular can thus be really the same without different concrete particulars of the same kind being really the same as each other.