We doubt that Daniel left the football. It is unlikely that Lily is a swan. It is probable that John went to the kitchen. We believe that if either 'John went to the kitchen' or 'Daniel left the football' but not both then Brian is a rhino. It is highly unlikely that if either 'Lily is a swan' or 'John went to the kitchen' but not both then Julius is gray. There is almost no chance that if either 'Daniel left the football' or 'Lily is a swan' but not both then Sandra got the milk.
It is probable that either 'Brian is a rhino' or 'John went to the kitchen' but not both.
It is probably not the case that either 'Brian is a rhino' or 'John went to the kitchen' but not both.
It is probable that either 'Brian is a rhino' or 'John went to the kitchen' 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
  0.2::factA.
  0.2::factB.
  0.7::factC.
  %hop1
  0.75::factX:-xor(factC,factA).
  0.05::factY:-xor(factB,factC).
  0.02::factZ:-xor(factA,factB).

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

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