Constance: Moon, Paradiso 3   This "great Constance" (Costanza) was the empress Constance (1152-98), wife of Henry VI, mother of Frederick II (the last dominant Holy Roman Emperor of the Middle Ages), and grandmother of Manfred. Like Piccarda, Constance was forced to leave her convent to enter into a political marriage. Dante's choice of Constance for the sphere of the Moon is a good example of his poetry of names, technically known as interpretatio nominis, which is based on an illuminating resonance between a person's name and his or her fate (or character). See Ciacco, Pier della Vigna, and Sapia. Here Dante exploits the traditional conception of the Moon as both the planet of Diana, the virgin goddess, and the planet of mutability or inconstancy. Piccarda, who was a "virgin sister" in the world (Par. 3.46), insists that though Costanza nominally broke her vows when she was forced to leave the convent, she nevertheless remained true to her promise--and thus to her name ("Constance")--in her heart (3.117).