Text: The Piazza del Duomo forms a harmonious space for the graceful octagonal baptistery, begun in 1196, and the austere nobility of the 12th-century Romanesque cathedral and its 13th-century campanile.
Entailment: There is a cathedral and a campanile in the Piazza del Duomo.
Contradiction: The baptistery in the Piazza del Duomo is hexagonal.