context: It is likely that John took the football. It is impossible that Julius is gray. Chances are about even that Lily is a swan.
hypothesis: It is almost certain that 'Lily is a swan and John took the football'.
valid_hypothesis: It is probably not the case that 'Lily is a swan and John took the football'.
invalid_hypothesis: It is almost certain that 'Lily is a swan and John took the football'.
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
    0.7::factA.
    0.0::factB.
    0.5::factC.
    
  
    %hop2
    conclusion:-and(factC,factA).
  
    query(conclusion).
    
hypothesis_assertion: 'Lily is a swan and John took the football'.