One way of reading Dante’s Divine Comedy is ‘vertically’, which means analyzing same-numbered cantos from two or three parts of the poem (canticles), Inferno, Purgatorio, Paradiso, for symmetrical meanings which become enriched by this clever juxtaposition. This is based on the presupposition that Dante built this symmetry into the poem as a whole, and expected a close reading of his work to reveal ‘hidden’ meanings. The vertical approach is already well-established, thanks to the work of George Corbett and Heather Webb. Although some cantos lend themselves better to this kind of reading than others (think of Inferno 1, Purgatorio 1, Paradiso 1 (‘the ones’) and their common theme of orientation, for instance), the verticality of Dante’s cantos, at least as a compositional and exegetical principle, is undeniable.
Cantos 4 of Purgatorio and Inferno are a good example of how this works. Inferno 4 is devoted to the first circle of Hell, the Limbo, where the pilgrim and his guide meet the unbaptised virtuous souls. Purgatorio 4 is about Mount Purgatory, its geo-spatial location and the meeting with Belacqua, Dante’s lazy friend. Despite their differences, the two cantos are, I think, linked by a common theme, and they may, for that reason, be read ‘vertically’. The theme is, well, verticality.
The two cantos have something to say about the topographies of Hell and Purgatory. Hell is a cone-like pit, while Purgatory a cone-like mountain. In Purgatorio 4, Dante notes with vivid detail how steep the mountain is:
Lo sommo er’ alto che vincea la vista,
e la costa superba più assai
che da mezzo quadrante a centro lista.
The summit was so high, my sight fell short;
the slope was far more steep than the line drawn
from middle—quadrant to the center point. (Purgatorio 4.40-42)
Many commentators have explained that the ‘quadrant’ refers to the quadrant circle, meaning one-fourth of a circle, so the gradient of a middle quadrant is 45%. No wonder Dante thought that he needed wings to scale the mountain (‘I had to fly: I mean with rapid wings and pinions of immense desire’, Purg 4.28-29).
In Inferno 4, Dante makes the same kind of observation about the appearance of Hell:
Oscura e profonda era e nebulosa
tanto che, per ficcar lo viso a fondo,
io non vi discernea alcuna cosa.
That valley, dark and deep and filled with mist,
is such that, though I gazed into its pit,
I was unable to discern a thing. (Inferno 4.10-12)
This time, the gradient is not important, because the pit is dark and appears to be bottomless. Both landscapes, however, strike the pilgrim, and us, as readers, through their verticality. One goes up, the other goes down. One is 45% steep, the other undiscernibly deep. It is against this backdrop – the radical ascent of purification and the equally radical descent of sin and death, that Dante foregrounds the lethargic but penitent Belacqua in Purgatorio 4 and the unbaptised virtuous pagans in Inferno 4.