DANTE ALIGHIERI (1265–1321), Italian poet, theologian, and philosopher. Dante offered in his Commedia a "sacred poem" of enormous erudition and aesthetic power, which more than any other work of Christian literature merits the appellation conferred on it by a mid-sixteenth-century edition: "divine." After producing the Vita nuova in 1295, Dante entered the volatile world of Florentine politics, which, however unjustly, subsequently led to his banishment from the city in 1302. In exile for the remainder of his life, he wrote the Convivio, the De vulgari eloquentia, and the De monarchia in the following decade, works that together reveal a commonality of themes: an admiration for the Latin classics, a dedication to the study of philosophy, and a commitment to the revival of the Roman imperial ideal. These concerns are all transfigured in the long and elaborate course of the Commedia (Inferno, Purgatorio, Paradiso), which represents an encyclopedic synthesis of...