People are gathered at a business conference.
There are no people in the picture.
If there are no people there can't be people gathered.
exists e1 x1 x2 x3.(at(e1,x2) & n_conference(x2) & of(x2,x3) & n_business(x3) & Theme(e1,x1) & v_gather(e1) & n_people(x1))
exists p1 x1 x2.(n_picture(x2) & in(p1,x2) & -exists x3.((x1 = x3) & n_people(x3)))