The "Commentary" of Proclus, the first part of which is presented in this edition, is a text of particular value. First of all, it includes the earliest surviving source today with a systematic account of ancient geometry, from its origins to shortly after the time of Euclid, a text based on now-lost histories of geometry, such as that of Eudoxus.

The mathematical part of the "Commentary" also has undeniable value. It is a fact that Proclus did not produce original mathematical work and that Neoplatonic influences led him to a systematic engagement with metaphysics. However, he was an exceptional commentator, annotator, and presenter of significant ancient texts, especially those of Plato.

(. . .) [Excerpt from the text of the preface]