Chances are slight that Brian is a rhino. Chances are slight that Bill went to the kitchen. It is almost certain that Julius is a swan. It is probably the case that if 'Brian is a rhino' or 'Bill went to the kitchen' or both then Jessica is a mouse. It is certain that if 'Brian is a rhino' or 'Bill went to the kitchen' or both then John got the apple. It is probably the case that if 'Bill went to the kitchen and Julius is a swan' then Mary moved to the garden.
It is improbable that either 'Jessica is a mouse' or 'Bill went to the kitchen' but not both.
It is improbable that either 'Jessica is a mouse' or 'Bill went to the kitchen' but not both.
There is a better than even chance that either 'Jessica is a mouse' or 'Bill 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
  0.1::factA.
  0.1::factB.
  0.95::factC.
  %hop1
  0.7::factX:-or(factA,factB).
  1.0::factY:-or(factA,factB).
  0.7::factZ:-and(factB,factC).

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

  query(conclusion).
  
Either 'Jessica is a mouse' or 'Bill went to the kitchen' but not both.