context: We doubt that John got the milk. We believe that Daniel left the milk. There is a better than even chance that Bernhard is green. Chances are slight that if 'Bernhard is green' or 'John got the milk' or both then Sumit is tired. Chances are slight that if 'Daniel left the milk and Bernhard is green' then Brian is a lion. It is highly likely that if 'Daniel left the milk and Bernhard is green' then Mary went to the office.
hypothesis: There is a better than even chance that 'Bernhard is green' or 'Sumit is tired' or both.
valid_hypothesis: There is a better than even chance that 'Bernhard is green' or 'Sumit is tired' or both.
invalid_hypothesis: There is little chance that 'Bernhard is green' or 'Sumit is tired' 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.
    0.75::factB.
    0.6::factC.
    %hop1
    0.1::factX:-or(factC,factA).
    0.1::factY:-and(factB,factC).
    0.9::factZ:-and(factB,factC).
  
    %hop2
    conclusion:-or(factC,factX).
  
    query(conclusion).
    
hypothesis_assertion: 'Bernhard is green' or 'Sumit is tired' or both.