context: There is a better than even chance that Brian is white. It is probably the case that Daniel left the milk. It is improbable that Bernhard is a rhino. We believe that if either 'Bernhard is a rhino' or 'Daniel left the milk' but not both then Julius is a swan. We believe that if 'Bernhard is a rhino' or 'Brian is white' or both then Gertrude is a wolf. It is probably not the case that if 'Daniel left the milk and Bernhard is a rhino' then John went to the office.
hypothesis: It is highly likely that 'Daniel left the milk' or 'Brian is white' or both.
valid_hypothesis: It is highly likely that 'Daniel left the milk' or 'Brian is white' or both.
invalid_hypothesis: There is almost no chance that 'Daniel left the milk' or 'Brian is white' or both.
problog: 
    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.
    0.7::factB.
    0.1::factC.
    %hop1
    0.75::factX:-xor(factC,factB).
    0.75::factY:-or(factC,factA).
    0.25::factZ:-and(factB,factC).
  
    %hop2
    conclusion:-or(factB,factA).
  
    query(conclusion).
    
hypothesis_assertion: 'Daniel left the milk' or 'Brian is white' or both.