premise: A windsurfer catching air with water streaming off of the board.
hypothesis: No one is windsurfing.
explanation_1: Catching air means some one is windsurfing.
explanation_2: If no one is windsurfing then the windsurfer cannot be catching air.
explanation_3: You cannot say a windsurfer is not in action when he/she is doing the action of windsurfing.
premise_logic: exists e2 e1 x1 x2 x3 x4 x5.(n_board(x5) & a_topic(x1) & of(e2,x5) & r_off(e2) & Actor(e2,x4) & v_stream(e2) & with(e1,x4) & n_water(x4) & Theme(e1,x3) & Actor(e1,x2) & v_catch(e1) & n_air(x3) & (x1 = x2) & n_windsurfer(x1))
hypothesis_logic: -exists e1 x1.(Actor(e1,x1) & v_windsurf(e1) & n_one(x1))