Foreword by Professor Emeritus of the University of Peloponnese and President of the Society of Greek Philologists Georgia Xanthakis-Karamanou .

The present work of Theon of Smyrna is widely remembered by historians of mathematics because it gives a lot of information about Pythagorean arithmetic, but also about music and astronomy of various periods of Ancient Greece. The project is divided into four sections:

In "Introduction", "Arithmetic", "Music" and "Astronomy". The first section deals with the usefulness of mathematics. In "Arithmetic" a clear reference is made to Pythagorean arithmetic. In "Music" almost all the elements of its theory are presented as they were formed until the time of Theon . In "Astronomy", finally, almost all the opinions of the Ancient Greek astronomers regarding the science of the Sky are presented, always in summary.