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Ontology; Metaphysics; Middle Ages; Phenomenology
In his phenomenological deconstruction (Destruktion) of medieval ontology, often associated with late Scholasticism, Heidegger restricts the metaphysics of being in Thomas Aquinas to effective reality. Heidegger interprets the thomistic act of being (actus essendi) as the transition from a mere potential being to its actuality, which determines the distinction between essence and existence, delineating the ontological constitution between what an entity is (essentia) and its mode of simply being given (Vorhandenheit). This thesis seeks to analyze whether this distinction, which equates being and entity in an ontic real effectiveness, applies to being (esse) in Thomas Aquinas as Heidegger understood it in his task of phenomenological deconstruction of traditional ontology. In his fundamental ontology, aimed at a return to the original sources of the question of the meaning of being that has fallen into oblivion due to the ontological difference as a symptom of Western metaphysics, Heidegger points to Thomas Aquinas as one of the main propagators of this concealment. However, this reference is made to the extent that Heidegger considers the metaphysics of Suarez as a hermeneutical key to the phenomenological analysis of Thomas Aquinas' thought