context: It is certain that Bill got the milk there. There is a better than even chance that John grabbed the apple. It is almost certain that Greg is a swan.
hypothesis: It is almost certain that 'Greg is a swan and Bill got the milk there'.
valid_hypothesis: It is almost certain that 'Greg is a swan and Bill got the milk there'.
invalid_hypothesis: It is probably not the case that 'Greg is a swan and Bill got the milk there'.
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
    1.0::factA.
    0.6::factB.
    0.95::factC.
    
  
    %hop2
    conclusion:-and(factC,factA).
  
    query(conclusion).
    
hypothesis_assertion: 'Greg is a swan and Bill got the milk there'.