Chances are slight that Julius is white. It is highly likely that Lily is a swan. It is almost certain that John got the milk. It is almost certain that if either 'John got the milk' or 'Lily is a swan' but not both then Brian is yellow. It is probably not the case that if either 'Lily is a swan' or 'Julius is white' but not both then Winona is a wolf. There is almost no chance that if either 'John got the milk' or 'Lily is a swan' but not both then Emily is a wolf.
It is impossible that 'Emily is a wolf and Brian is yellow'.
It is impossible that 'Emily is a wolf and Brian is yellow'.
It is probable that 'Emily is a wolf and Brian is yellow'.

  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
  0.1::factA.
  0.9::factB.
  0.95::factC.
  %hop1
  0.95::factX:-xor(factC,factB).
  0.25::factY:-xor(factB,factA).
  0.02::factZ:-xor(factC,factB).

  %hop2
  conclusion:-and(factZ,factX).

  query(conclusion).
  
'Emily is a wolf and Brian is yellow'.