Chances are slight that Brian is a swan. We doubt that Emily is a sheep. We believe that Greg is a rhino. It is probable that if either 'Emily is a sheep' or 'Greg is a rhino' but not both then Julius is gray. There is a better than even chance that if 'Brian is a swan' or 'Greg is a rhino' or both then John went to the garden. It is almost certain that if either 'Brian is a swan' or 'Emily is a sheep' but not both then Lily is white.
It is highly unlikely that either 'Emily is a sheep' or 'Greg is a rhino' but not both.
It is likely that either 'Emily is a sheep' or 'Greg is a rhino' but not both.
It is highly unlikely that either 'Emily is a sheep' or 'Greg is a rhino' 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.
  0.2::factB.
  0.75::factC.
  %hop1
  0.7::factX:-xor(factB,factC).
  0.6::factY:-or(factA,factC).
  0.95::factZ:-xor(factA,factB).

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

  query(conclusion).
  
Either 'Emily is a sheep' or 'Greg is a rhino' but not both.