The second movement, entitled Purgatorio, depicts Dante and Virgil's ascent of Mount Purgatory. It is Ternary in structure. The first section is solemn and tranquil and in two parts; in the second section, which is more agitated and lamentable, a fugue is built up to a grand climax; in the final section there is a return to the mood of the opening, the principal themes of which are recapitulated. This tripartite structure reflects the architecture of Dante's Mount Purgatory, which can also be divided into three parts: the two terraces of Ante-Purgatory, where the excommunicate and the late repentant expiate their sins; the seven cornices of Mount Purgatory proper, where the Seven Deadly Sins are expiated; and the Earthly Paradise at the summit, from which the soul, now purged of sin, ascends to Paradise.
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