 But Burley’s explanation, however interesting, has a weak point, since it does not clarify how it is possible for the material intellect to know an individual existing outside our mind by means of a singular intentional representation that is not present in it, but in elementary thought. The solution to this problem lies in what he says in the aformentioned q.5 of Book I, as well as in q.10 of Book III (“utrum intellectus materialis copuletur nobis solum per phantasma [Is the material intellect joined to us only through an image]?”, fol. 76va–b), concerning the problem of the union (copulatio) of singular human beings with the material intellect, which is assumed to be separate and unique for the whole human species. In his view, the material intellect is by nature united with human individuals from birth, as the perfection of their being. But a further kind of union takes place when the material intellect performs an act of understanding (in operando), i.e., when the active intellect illumines both the phantasm and the material intellect, thereby impressing on the latter the species intelligibilis abstracted from the former—intelligible species by means of which the material intellect can grasp the common nature of the singular substance which began the process of knowing. This close connection between the phantasm and the intelligible species (which originates from it) is why (1) the material intellect can know singulars through a representation that is not properly present in it; and conversely, (2) the elementary thought can know, indirectly and derivatively, common natures (or universals) (“homo per virtutem cogitativam potest cognoscere universalia et quidditates rerum”, fol. 13va), even though its proper and adequate object is the singular.