It is highly likely that Greg is a swan. It is highly unlikely that Bernhard is a rhino. We believe that Mary moved to the garden. It is likely that if either 'Bernhard is a rhino' or 'Greg is a swan' but not both then Daniel got the milk. It is probable that if either 'Mary moved to the garden' or 'Greg is a swan' but not both then John went to the kitchen. We doubt that if either 'Bernhard is a rhino' or 'Mary moved to the garden' but not both then Brian is yellow.
Chances are about even that 'John went to the kitchen' or 'Greg is a swan' or both.
It is almost certain that 'John went to the kitchen' or 'Greg is a swan' or both.
Chances are about even that 'John went to the kitchen' or 'Greg is a swan' or 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
  0.9::factA.
  0.05::factB.
  0.75::factC.
  %hop1
  0.7::factX:-xor(factB,factA).
  0.7::factY:-xor(factC,factA).
  0.2::factZ:-xor(factB,factC).

  %hop2
  conclusion:-or(factY,factA).

  query(conclusion).
  
'John went to the kitchen' or 'Greg is a swan' or both.