premise: A biker gets high in the air against a skyline.
hypothesis: The biker is on a dirt bike.
explanation_1: You can not infer he is on a dirt bike.
explanation_2: STUNTS CAN BE PERFORMED IN BIKES OTHER THAN DIRT BIKES TOO.
explanation_3: A biker can ride any type of bike other than a dirt bike to get high in the air.
premise_logic: exists e1 p1 x1 x2 x3.(n_air(x2) & in(e1,x2) & against(x2,x3) & n_skyline(x3) & exists s1.(Theme(s1,x1) & a_high(s1)) & Topic(e1,p1) & Actor(e1,x1) & v_get(e1) & n_biker(x1))
hypothesis_logic: exists p1 x1.(n_biker(x1) & exists x2 x3.(on(x1,x2) & n_bike(x2) & of(x2,x3) & n_dirt(x3)))