context: Chances are about even that John put down the apple. It is impossible that Greg is a lion. There is almost no chance that Lily is green.
hypothesis: Chances are about even that 'Lily is green and John put down the apple'.
valid_hypothesis: There is almost no chance that 'Lily is green and John put down the apple'.
invalid_hypothesis: Chances are about even that 'Lily is green and John put down the apple'.
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
    0.5::factA.
    0.0::factB.
    0.02::factC.
    
  
    %hop2
    conclusion:-and(factC,factA).
  
    query(conclusion).
    
hypothesis_assertion: 'Lily is green and John put down the apple'.