There is a very good chance that Winona is a wolf. We doubt that Brian is green. It is almost certain that John went to the hallway. It is probably the case that if either 'Winona is a wolf' or 'Brian is green' but not both then Sandra left the milk. Chances are about even that if 'Brian is green and Winona is a wolf' then Bernhard is a swan. It is highly likely that if 'Brian is green and John went to the hallway' then Daniel dropped the apple.
We believe that 'Bernhard is a swan' or 'Daniel dropped the apple' or both.
It is unlikely that 'Bernhard is a swan' or 'Daniel dropped the apple' or both.
We believe that 'Bernhard is a swan' or 'Daniel dropped the apple' 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
  0.8::factA.
  0.2::factB.
  0.95::factC.
  %hop1
  0.7::factX:-xor(factA,factB).
  0.5::factY:-and(factB,factA).
  0.9::factZ:-and(factB,factC).

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

  query(conclusion).
  
'Bernhard is a swan' or 'Daniel dropped the apple' or both.