There is a very good chance that John went to the hallway. It is almost certain that Lily is green. Chances are slight that Winona is a wolf. There is almost no chance that if 'Winona is a wolf and Lily is green' then Julius is a rhino. It is improbable that if 'John went to the hallway' or 'Winona is a wolf' or both then Brian is a frog. There is little chance that if either 'Lily is green' or 'John went to the hallway' but not both then Mary is in the bathroom.
There is a very good chance that either 'Julius is a rhino' or 'John went to the hallway' but not both.
There is a very good chance that either 'Julius is a rhino' or 'John went to the hallway' but not both.
It is highly unlikely that either 'Julius is a rhino' or 'John went to the hallway' 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
  0.8::factA.
  0.95::factB.
  0.1::factC.
  %hop1
  0.02::factX:-and(factC,factB).
  0.1::factY:-or(factA,factC).
  0.1::factZ:-xor(factB,factA).

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

  query(conclusion).
  
Either 'Julius is a rhino' or 'John went to the hallway' but not both.