Alexander Rehding and John McKay (both musicologists at Harvard U.) have published an article in the most recent issue of Apeiron on the musical structures in Plato’s dialogues. I welcome this erudite and constructive paper.
Their main point is that the 12-note, symbolic ‘scale’ found in Plato’s dialogues is not one of the conventional scales used by ancient performers of Greek music. This is correct. As others have pointed out, the scale is really a ‘division of the canon’ and was constructed by music theorists to exhibit the most important musical harmonies. The 12-note scale was well-known to theorists and is described explicitly by Theon of Smyrna in his first century On the Mathematics Useful for Reading Plato. Theon describes this ‘scale’ as a way of dividing the string on a monochord (a canon), and it is probable that this 12-note scale emerged in this context and not performance.
I have drafted a paper replying to Rehding and McKay. Please email me if you would like a pdf: comments and criticism are welcome. There are two appendices on the musicological background to Plato’s symbolism in my book, The Musical Structure of Plato’s Dialogues, and many of Rehding’s and McKays questions are answered there.