context: We doubt that Brian is yellow. There is a very good chance that Julius is white. We doubt that Winona is a sheep. It is impossible that if either 'Winona is a sheep' or 'Julius is white' but not both then Sumit is thirsty. It is impossible that if either 'Julius is white' or 'Winona is a sheep' but not both then Bernhard is a swan. It is impossible that if 'Julius is white' or 'Winona is a sheep' or both then Sandra dropped the milk.
hypothesis: It is highly likely that 'Sumit is thirsty' or 'Brian is yellow' or both.
valid_hypothesis: It is unlikely that 'Sumit is thirsty' or 'Brian is yellow' or both.
invalid_hypothesis: It is highly likely that 'Sumit is thirsty' or 'Brian is yellow' 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
    0.2::factA.
    0.8::factB.
    0.2::factC.
    %hop1
    0.0::factX:-xor(factC,factB).
    0.0::factY:-xor(factB,factC).
    0.0::factZ:-or(factB,factC).
  
    %hop2
    conclusion:-or(factX,factA).
  
    query(conclusion).
    
hypothesis_assertion: 'Sumit is thirsty' or 'Brian is yellow' or both.