formulas(sos). % Sorting on WorldAt all x all d (WorldAt(x,d) -> Object(x) & Point(d)). % L1 all x (Object(x) -> ((exists d (Point(d) & WorldAt(x,d))) -> (all d (Point(d) -> WorldAt(x,d))))). % Corollary to L2 all x all p ((Object(x) & Proposition(p)) -> ((exists d (Point(d) & TrueInAt(p,x,d))) -> (all d (Point(d) -> TrueInAt(p,x,d))))). % L3 all x all d ((Object(x) & Point(d)) -> ((WorldAt(x,d) & ActualAt(x,d)) -> (all p (Proposition(p) -> (TrueInAt(p,x,d) <-> True(p,d)))))). % L4 all d (Point(d) -> (exists x (WorldAt(x,d) & ActualAt(x,d)))). % Distinguished Point. Point(W). % Definition of PossiblyTrue all p (PossiblyTrue(p) <-> (exists d (Point(d) & True(p,d)))). % Definition of World(x) all x (World(x) <-> WorldAt(x,W)). % Definition of TrueIn all x all p (TrueIn(p,x) <-> TrueInAt(p,x,W)). end_of_list.