Virtually nothing remains of works in the musical sciences written between the time of Euclid and the end of the first century b.c. We know that the subjects continued to be studied, and a few individual contributions can be reconstructed from references in Ptolemy and later writers, but for the most part the authors of the early Christian era say little directly about their immediate predecessors, leaving us to infer the character of the contents of the gap from that of their own work. Even from the first century a.d. no complete treatises survive (unless 10 Nicomachus Enchiridion belongs to its last years), but substantial passages are preserved as quotations in later essays. In this chapter I have put together a selection of them, some from writers of the first century, others a little later; in a few cases the dates are quite uncertain.

The excerpts are drawn from two authors, Theon of Smyrna and Porphyrius of Tyre, more commonly known as Porphyry. Neither made major contributions to the subject in his own right, though Porphyry certainly had ideas of his own to convey, and his intellectual powers are much more impressive than Theon's. For a modern student the main value of both treatises lies in their quotations and paraphrases of previous writers.

Part 1 Passages from Theon of Smyrna

Theon wrote during the second century a.d. He devoted himself to the works of Plato, and is known to have written scholarly essays about him, including a commentary on the Republic.