context: We believe that Lily is a frog. It is highly unlikely that Daniel took the milk. There is little chance that Brian is green.
hypothesis: It is impossible that 'Brian is green and Daniel took the milk'.
valid_hypothesis: It is impossible that 'Brian is green and Daniel took the milk'.
invalid_hypothesis: Chances are about even that 'Brian is green and Daniel took the milk'.
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
    0.75::factA.
    0.05::factB.
    0.1::factC.
    
  
    %hop2
    conclusion:-and(factC,factB).
  
    query(conclusion).
    
hypothesis_assertion: 'Brian is green and Daniel took the milk'.