Ratio and modus essendi of the categories. Thomas Aquinas, Henry of Ghent and John Duns Scotus

In the Middle Ages, the transmission and the reception of Aristotle's Categories, together with Porphyrius's isagoge, a work that had driven to a predominantly logical-linguistic approach, have led to both extensional and intensional interpretation about categories. This exegesis found support also from the second intentions doctrine and their relation with reality. The determining ontological status of categories moves in parallel with universals' theories, while second intentions allow understanding the categories' general character. Categories' theory is based on lexical signification doctrine, associated with an ontology. Here we'll examine Thomas Aquinas', Henry of Ghent's, and John Duns Scotus' positions.