Text: Room 17: Canaletto's hugely popular 18th-century vedute (views) of Venice were aristocratic precursors of modern postcards; in such works as Island of San Giorgio Maggiore, Francesco Guardi achieved both poetry and melancholy.
Entailment: Canaletto's works were the 18-century version of a modern postcard.
Contradiction: Despite the beauty of Canaletto's works, they never became popular.