Commentary Purg XXIII 3

For perdere la vita as meaning simply 'to spend one's life,' and as not necessarily implying any negative moralizing judgment, see Jenni (Jenn.1972.1), p. 1n.  The context here (Virgil's gentle chiding), however, would seem to support the more usual interpretation, one that sees the phrase as negative ('waste one's life').  In [Purg XXXI 61-63], the poet compares his earlier lustful self to a young bird being pursued by hunters.  Barolini (Baro.1984.1), pp. 46-48, notes the way in which Forese's final words ([Purg XXIII 91-93]) reflect this concern with wasting time and also suggests a connection between the diminutive pargoletta (young girl) in that later passage and the diminutive uccellino here; in this way Dante would be associating the apparently innocent 'sport' of birding with his sexual disloyalty to Beatrice.