There is a better than even chance that Mary took the milk. It is probable that Emily is a wolf. It is highly unlikely that Julius is a swan. It is probably not the case that if 'Julius is a swan and Mary took the milk' then Jessica is a sheep. It is probably not the case that if 'Julius is a swan' or 'Mary took the milk' or both then Jason is tired. There is a very good chance that if 'Mary took the milk and Emily is a wolf' then Bernhard is a frog.
It is highly unlikely that either 'Jason is tired' or 'Emily is a wolf' but not both.
There is a better than even chance that either 'Jason is tired' or 'Emily is a wolf' but not both.
It is highly unlikely that either 'Jason is tired' or 'Emily is a wolf' 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
  0.6::factA.
  0.7::factB.
  0.05::factC.
  %hop1
  0.25::factX:-and(factC,factA).
  0.25::factY:-or(factC,factA).
  0.8::factZ:-and(factA,factB).

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

  query(conclusion).
  
Either 'Jason is tired' or 'Emily is a wolf' but not both.