set(ignore_option_dependencies). % GUI handles dependencies

if(Prover9). % Options for Prover9
  assign(max_seconds, 60).
end_if.

if(Mace4).   % Options for Mace4
  assign(max_seconds, 60).
end_if.

formulas(assumptions).

all x (shark(x) -> -herb(x)).
exists x (fish(x)).
all x all y (shark(x) & fish(y) -> eats(x,y)).
all x (fish(x) -> animal(x)).
all x all y (herb(x) & animal(y) -> -eats(x,y)).

end_of_list.

formulas(goals).

all x (shark(x) -> -herb(x)).

end_of_list.

