Theon was a teacher of Platonism and an exegete of Plato’s text in the flourishing town of Smyrna during the first and second century of our age (fl. 125 A. D.). The Expositio is the only work of Theon that has been transmitted to us. It is an important witness in order to grasp not only the approach to mathematics (arithmetic, music and astronomy) typical of a middle-Platonist, but also (and above all) the exegetic aims of this project.
Here the Expositio is translated ininto Italian for the first time, with a deep revisal of the Teubner text. The commentary shows that this work is a technical exegesis of the Timaeus, an attempt to argue that Plato has grasped in the most authentic way the true structure of the cosmos. On this basis, it is possible to see at work methods, intentions and strategies of a middle-Platonist engaged in the reargumentation of the Timaeus.