%% pmtest.pl -- test file for MP interpreter.

parent(adam,able) if true.
parent(adam,cain) if true.
parent(eve,able) if true.
parent(eve,cain) if true.
male(adam) if true.
female(eve) if true.
father(X,Y) if parent(X,Y) and male(X).
mother(X,Y) if parent(X,Y) and female(X).
sibling(X,Y) if
  father(Pa,X) and
  father(Pa,Y) and
  mother(Ma,X) and
  mother(Ma,Y) and
  ~(X=Y).