A pitcher is about to throw a baseball.
Nobody has a baseball
The pitcher has a baseball so there is somebody with a baseball.
exists p1 s1 x1.(Topic(s1,p1) & Actor(s1,x1) & a_about(s1) & exists e1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_throw(e1) & n_baseball(x2)) & n_pitcher(x1))
-exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_have(e1) & n_baseball(x2) & n_person(x1))