The Spartan Rhetra in Plutarch Lycurgus VI

The Spartan Rhetra quoted by Plutarch in Lyc. vi. 2 consists of some thirty-seven words in an archaic Dorian or near-Dorian dialect: Plutarch says it was an oracle, and that later an extra clause was added by the kings Polydoros and Theopompos; he quotes this ‘added clause’ in vi. 8. I believe this Rhetra was not an oracle but an act of the Spartan Ekklesia; and I suspect that the ‘added clause’ was not added, but is an integral part of the original act. But for our first objective this opinion matters less than Plutarch's opinion. Our first objective must be to recover Plutarch's text (for his manuscripts are certainly corrupted to some extent): and to do that, we must understand his interpretation.