Commentary Purg XXXII 38-42

The tree, given the context, is, literally, the Tree of the Knowledge of Good and Evil.  However, some of the first commentators (e.g., the Anonymus Lombardus [DDP Lombardus.Purg.XXXII.38-39], Jacopo della Lana [DDP Lana.Purg.XXXII.38-42]), disregarding that context, think its withered condition indicates the Tree of Life after the original sin, when humankind lost eternal life, a perfectly sensible (if almost certainly erroneous) conclusion.  Benvenuto (DDP Benvenuto.Purg.XXXII.37-39), paying attention to what is said of the tree in the next canto ([Purg XXXIII 61-63]), only reasonably concludes that this tree, eaten of by Adam when he followed Eve in sin, must be the Tree of the Knowledge of Good and Evil.  While there have been many other interpretations (DDP Scartazzini.Purg.XXXII.38) claims that not a single gloss but a book would be necessary to document them all -- and indeed his gloss itself is article-length), most currently agree with Benvenuto, but also with Scartazzini's view that the allegorical sense of the tree relates it to the history of the Roman empire.

      For the current debate over the meaning of the tree, see Armour (Armo.1989.1), pp. 180-214, and Pertile (Pert.1998.2), pp. 163-96; see also Kaske (Kask.1971.2), p. 50.

      One literary source of Dante's tree, which, as Scartazzini and Pertile point out, has any number of biblical analogues (e.g., Judges 9:8, Ezekiel 17:24, Daniel 4:20-22) -- Pertile (Pert.1998.2), p. 166; Song of Songs (7:7-8) was first suggested by John of Serravalle (DDP Serravalle.Purg.XXXII.37-42): Georgics II.122-124, describing enormously tall trees in India.  We probably should assume that this tree, like those found on two of the terraces below (see [Purg XXII 131-135]; [Purg XXIV 103-105]), has its boughs pointed downward so as to prevent its being climbed.