There is a better than even chance that Mary went to the hallway. It is unlikely that Daniel left the apple. We doubt that Bernhard is a swan. We doubt that if either 'Bernhard is a swan' or 'Daniel left the apple' but not both then John moved to the garden. Chances are slight that if either 'Bernhard is a swan' or 'Daniel left the apple' but not both then Jason is tired. It is certain that if either 'Daniel left the apple' or 'Bernhard is a swan' but not both then Sandra got the milk.
It is highly likely that 'Bernhard is a swan and Daniel left the apple'.
It is highly unlikely that 'Bernhard is a swan and Daniel left the apple'.
It is highly likely that 'Bernhard is a swan and Daniel left the apple'.

  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
  0.6::factA.
  0.2::factB.
  0.2::factC.
  %hop1
  0.2::factX:-xor(factC,factB).
  0.1::factY:-xor(factC,factB).
  1.0::factZ:-xor(factB,factC).

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

  query(conclusion).
  
'Bernhard is a swan and Daniel left the apple'.