It is probable that Bernhard is a frog. It is impossible that Sandra left the milk. There is a better than even chance that Julius is yellow. It is certain that if either 'Bernhard is a frog' or 'Sandra left the milk' but not both then Brian is a rhino. It is probable that if 'Bernhard is a frog' or 'Julius is yellow' or both then Lily is a lion. It is probably not the case that if 'Bernhard is a frog and Sandra left the milk' then John dropped the apple.
It is probably not the case that either 'Lily is a lion' or 'Bernhard is a frog' but not both.
It is probably not the case that either 'Lily is a lion' or 'Bernhard is a frog' but not both.
It is almost certain that either 'Lily is a lion' or 'Bernhard is a frog' but not both.

  and(A,B) :- A,B.
  or(A,B) :- A;B.
  nand(A,B) :- not(and(A,B)).
  nor(A,B) :- not(or(A,B)).
  xor(A,B) :- or(A,B), nand(A,B).

  %hop0
  0.7::factA.
  0.0::factB.
  0.6::factC.
  %hop1
  1.0::factX:-xor(factA,factB).
  0.7::factY:-or(factA,factC).
  0.25::factZ:-and(factA,factB).

  %hop2
  conclusion:-xor(factY,factA).

  query(conclusion).
  
Either 'Lily is a lion' or 'Bernhard is a frog' but not both.