context: It is impossible that Mary moved to the office. There is a better than even chance that Julius is a swan. We doubt that Greg is a lion.
hypothesis: It is almost certain that 'Julius is a swan and Greg is a lion'.
valid_hypothesis: There is little chance that 'Julius is a swan and Greg is a lion'.
invalid_hypothesis: It is almost certain that 'Julius is a swan and Greg is a lion'.
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
    0.0::factA.
    0.6::factB.
    0.2::factC.
    
  
    %hop2
    conclusion:-and(factB,factC).
  
    query(conclusion).
    
hypothesis_assertion: 'Julius is a swan and Greg is a lion'.