 In his commentary on the Categories, Paul explains that the direct and adequate objects of propositions, which make them true, are molecular things (res complexae) existing outside the soul. Such entities are complexe significabilia, the significata of propositions, that is extramental realities made up of a subject-form and a predicate-form linked together in one and the same substance or set of substances (In Cat., cap. de subiecto et praedicato, fol. 48ra). Thus, Paul’s approach to the question of the truth of a proposition is ontological, as is Gregory’s, since according to him the true is an attribute of things and only secondarily of thought, but at the same time it is consistent with the fundamental principle of every form of correspondence theory of truth, that of the isomorphism of language, thought, and the world. In fact, in his commentary on the Metaphysics Paul distinguishes three different but connected kinds of truth: truth of imitation (veritas imitationis), truth of disclosure (veritas manifestationis), and relational truth (veritas respectiva). The first type of truth is the measure of the conformity (adaequatio) which all the things have in relation to their corresponding ideas in the mind of God, from which they derive. The second type is also a real property of extramental things, which measures their various degrees of disposition to be apprehended by our intellect. Relational truth, unlike the first two veritates, is not an absolute property of things, but, just as its name suggests, a relation, and more precisely a relation of conformity which has its substrate of existence in our intellect, its fundamentum in mental sentences, and its terminus ad quem in the molecular objects existing outside the soul. Despite the fact that it is related to the activity of the intellect, the veritas respectiva is the effect caused in our intellect by the existence of the veritas manifestationis. If things were not intelligible by themselves, they could not be grasped and recognised by our intellect for what they are (In Metaph., lib. VI, cap. 4, fol. 233rb–va). So, like Gregory, Paul also supports the idea that human knowledge is true only qua knowledge of the ontological truth, and that sentences are true only in so far as they are signs of the ontological truth.