The horse on the right is red.
There is a red horse and a white horse.
No way to know that there is a white horse.
exists s1 x1 x2.(n_right(x2) & n_horse(x1) & Theme(s1,x1) & a_red(s1) & on(x1,x2))
exists p1 x1 s1 s2 x2 x3 x4.((x1 = x2) & subset_of(x4,x2) & n_horse(x4) & a_white(s2) & Theme(s2,x4) & subset_of(x3,x2) & n_horse(x3) & a_red(s1) & Theme(s1,x3))