premise: Two girls, one with dark hair, wearing glasses and red pants, the other with a blue shirt and jeans with blond-hair talking and walking down a sidewalk. hypothesis: An old pirate shows off all his extreme tattoos.
contradiction: Either there are two girls talking and walking down a sidewalk or there is an old pirate showing off his extreme tattoos.|contradiction: An old pirate is not two girls.|contradiction: Neither of the two girls is the old pirate.  The pronoun that is used to describe his tattoos makes it clear that it is a man.