at this time,—the plan of the great poem for whose completion the experience of earth and the inspiration of heaven were to combine, and which was to make him lean for many years.1
The doctrinal scope of it was already determined.
Man, he tells us, is the only creature who partakes at once of the corruptible and incorruptible nature; ‘and since every nature is ordained to some ultimate end, it follows that the end of man is double.
And as among all beings he alone partakes of the corruptible and incorruptible, so alone among all beings he is ordained to a double end, whereof the one is his end as corruptible, the other as incorruptible.
That unspeakable Providence
therefore foreordered two ends to be pursued by man, to wit, beatitude in this life, which consists in the operation of our own virtue, and is figured by the Terrestrial Paradise
, and the beatitude of life eternal, which consists in a fruition of the divine countenance, whereto our own virtue cannot ascend unless aided by divine light, which is understood by the Celestial Paradise
The one we attain by practice of the moral and intellectual virtues as they are taught by philosophers, the other by spiritual teachings transcending human reason, and the practice of the theological virtues of Faith, Hope, and Charity.
For one, Reason suffices (‘which was wholly made known to us by philosophers’), for the other we need the light of supernatural truth revealed by the Holy Spirit
and ‘needful for us.’
Men led astray by cupidity turn their backs on both, and in their bestiality need bit and rein to keep them in the way. ‘Wherefore to man was a double guidance needful according to the double end,’ the Supreme Pontiff
in spiritual, the Emperor
in temporal things.2