Commentary Purg XXXIII 46-51

The general sense of this passage is clear: future events will make plain the terms of the cloudy prophecy, which is compared to those made by Themis (Metam. I.375-394) and by the Sphinx.  Both of these monstrous females later appear in the same passage in Ovid (Metam. VII.759-765), where their hatred of humans is, as here, described in terms of the loss of human and animal life in the countryside.  The key lines in the modern text of Ovid run as follows: 'Carmina Laïades non intellecta priorum / solverat ingeniis...' (The son of Laius [Oedipus] solved the riddles which had baffled the intellects of all before him).  We are close to being absolutely sure, however, that the text as Dante knew it substituted 'Naïades' for 'Laïades' and showed a plural form of the verb (solverant).  And so Dante believed that it was the Naiads, water nymphs, who had solved the riddle of the Sphinx.  This was the cruel monster who cast herself down from her rock, whence she had been killing clueless Thebans, once Oedipus realized that the variously footed creature in her riddle was man (the story that we know from Sophocles' Oedipus, unknown, like nearly all of Greek letters, to Dante).

      Dante does not 'nod' often, and this is one of the most egregious errors in the Comedy, even if it has some reasonable excuse behind it.  In fact, all of the early commentators accept Dante's reading, thus indicating that their texts also had 'Naiads' where they should have had Laius's son.  The better reading had to wait for Nikolaes Heinsius (1620-81), the Dutch Latin poet and scholar, one of the great Renaissance textual editors of the Latin classics.  His edition (Florence, 1646) of the Metamorphoses restored the reading Laïades.  It is thus only with the commentary of Venturi (DDP Venturi.Purg.XXXIII.49-50) that the better reading is made known to the world of Dante's commentators, and even then some of them try to object to it, seeking a way to understand the Naiads as interpreters of prophetic utterance.  Ghisalberti (Ghis.1932.1) offers a comprehensive discussion of the problem.