premise: A person on a motorcycle.
hypothesis: a man on a motorcycle
explanation_1: Not every persons is a man.
explanation_2: A man is not the only person that can be on a motorcycle.
explanation_3: Just because a person on a motorcycle, doesn't mean it is a man.
premise_logic: exists x1 x2.(a_topic(x1) & on(x1,x2) & n_motorcycle(x2) & n_person(x1))
hypothesis_logic: exists x1 x2.(a_topic(x1) & on(x1,x2) & n_motorcycle(x2) & n_man(x1))