On the Correct Reading of Metaphysics V 7, 1017a 34–35. The Logic Behind Aristotle’s Example of the Diagonal

Abstract

This paper aims to clarify the opposition between Alexander of Aphrodisias, followed by Hermann Bonitz on one side, and Thomas Aquinas, followed by Lambertus Marie de Rijk on the other, regarding the correct reading of an example proposed by Aristotle in Metaphysics V 7, 1017a 34–35, which involves the diagonal and its incommensurability with the side. The author aims to demonstrate that Aquinas’s interpretation (and De Rijk’s one) cannot be accepted and that we should follow Alexander of Aphrodisias and Bonitz.