In Dante's Commedia, Beatrice informs Dante that the souls he sees in the sphere of the moon do not actually inhabit it. They are in the lowest celestial sphere as a sign of the rank they occupy in heaven. This manner of communicating with Dante, she says, has been necessitated by the nature of the human being's ingegno (intellect), to which the divine communication that is Dante's meeting with the souls is addressed.

Taking this passage as a succinct explanation of the manner in which the Commedia was written, this study investigates what Dante refers to as the ingegno. All uses of ingegno in the Commedia are examined, and the conception of the ingegno that emerges is traced to its sources.