It is probably the case that Winona is a wolf. There is almost no chance that Jessica is a mouse. It is improbable that Bernhard is a frog. It is impossible that if either 'Jessica is a mouse' or 'Bernhard is a frog' but not both then Lily is gray. We doubt that if 'Winona is a wolf and Jessica is a mouse' then Mary got the milk. We doubt that if 'Jessica is a mouse' or 'Bernhard is a frog' or both then John moved to the office.
It is highly unlikely that either 'Jessica is a mouse' or 'John moved to the office' but not both.
It is highly unlikely that either 'Jessica is a mouse' or 'John moved to the office' but not both.
There is a better than even chance that either 'Jessica is a mouse' or 'John moved to the office' 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.
  0.02::factB.
  0.1::factC.
  %hop1
  0.0::factX:-xor(factB,factC).
  0.2::factY:-and(factA,factB).
  0.2::factZ:-or(factB,factC).

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

  query(conclusion).
  
Either 'Jessica is a mouse' or 'John moved to the office' but not both.