Anchor: Why else should astrology be the greatest of the sciences?"  It was a nice world, he decided.
Entailed: What other reason would astrology be the best of the sciences?
Contradiction: Astrology is the worst of sciences.
Contradiction: A guy stands by the Mexican boarder.
Contradiction: The tour can take longer than half a day.
Contradiction: Four children playing a game.
Contradiction: A dog does tricks.