Commentary Par XVIII 82

The winged horse Pegasus struck the ground on Mt. Helicon with his hoof.  There sprang forth Hippocrene, the fountain sacred to the Muses.  Which one of them does the poet invoke here?  The most popular choices (given in historical order) are (1) Minerva, 'Wisdom,' as a sort of 'super muse' (first suggested by Jacopo della Lana [DDP Lana.Par.XVIII.82-87]); (2) a nonspecific, 'generic' muse (first, Benvenuto [DDP Benvenuto.Par.XVIII.82-87]); (3) invoked for the second time in the poem (see [Purg I 9]), Calliope, the Muse of epic (first, Vellutello [DDP Vellutello.Par.XVIII.82-84], and the 'majority candidate'); (4) also invoked for the second time (see [Purg XXIX 41]), Urania, the heavenly Muse (first, Andreoli [DDP Andreoli.Par.XVIII.82]).  This is a vexed question, with four fairly popular solutions (and a few others, e.g., Euterpe [DDP Torraca.Par.XVIII.82-84] and Clio [DDP Momigliano.Par.XVIII.82]) and no clear consensus.  All one can say is that the poet really seems to have a particular Muse in mind, since he addresses her with the singular 'tu' ([Par XVIII 87]).

In apparent support of Minerva is the passage in Ovid (Metam. V.250-272) in which she is portrayed as visiting Mt. Helicon, where she is welcomed by the nine Muses.  Then, unidentified, one of the Muses (almost certainly not Urania, the preceding speaker) addresses her, saying that, had she not been charged with greater tasks (Metam. V.269), she might have been free to join them.  This probably ought to rule Minerva out (and Urania, as well), but we cannot be certain that Dante was thinking of those details when he wrote this passage.