 … The third reason is that this sort of exemplar, since it is the intention and species of the sensible thing abstracted from the phantasm, is similar to the false as well as to the true [thing], so that on its account these cannot be distinguished. For it is by means of the same images of sensible things that in dreams and madness we judge these images to be the things, and in sane awareness we judge the things themselves. But the pure truth can only be perceived by discerning it from falsehood. Therefore, by means of such an exemplar it is impossible to have certain knowledge, and certain cognition of the truth. And so if we are to have certain knowledge of the truth, then we have to turn our mind away from the senses and sensible things, and from every intention, no matter how universal and abstracted from sensible things, to the unchangeable truth existing above the mind […]. [ibid., fol. 5. F]