consult(init).
goedel.
;cs DB.
;c DB.
;l DB.

ALL [x] (SOME [y] Mother(y, x) -> SOME [z] Father(z,x)).

ALL [x] (Mother(_, x) -> Father(_, x)).

SOME [z] Mother(x, z) & ~ SOME [y] Father(y, x).

Mother(x, _) & ~ Father(_, x).

x: Parent(x, y) & Parent(y, Jane).

SOME [y] (Parent(x, y) & Parent(y, Jane)).

halt.