context: Person doing a trick on a skateboard in a skate park while people watch.
hypothesis: It is impossible that there is a person doing leg presses at the local gym.
valid_hypothesis: It is impossible that there is a person doing leg presses at the local gym.
invalid_hypothesis: It is certain that there is a person doing leg presses at the local gym.
hypothesis_assertion: There is a person doing leg presses at the local gym.