ANA GABRIELA VILHENA DE MELLO SANTOS

This research investigates the term οὐσία (ousia) in Aristotle's works "Metaphysics" and "Categories," analyzing the meanings of this term based on specific excerpts from the works in order to comprehend Aristotle's theory of substance (ousiology). Since the notion of οὐσία occupies the center of Aristotle's ontology and more truly corresponds to what properly is a being (Met. Z1 1028a30-31), it is necessary to analyze the numerous difficulties surrounding this term to understand Aristotle's Aristotelian notion of οὐσία. Thus, this investigation will focus on examining the ways in which "substance" is presented in Categories 5 and in Metaphysics Ζ, presenting the difficulties involving the term οὐσία and highlighting how these difficulties multiply in different analyses of the term's occurrence.