context: Chances are about even that Lily is yellow. We doubt that Bernhard is a rhino. It is probable that Fred left the football.
hypothesis: It is improbable that 'Fred left the football and Bernhard is a rhino'.
valid_hypothesis: It is improbable that 'Fred left the football and Bernhard is a rhino'.
invalid_hypothesis: There is a very good chance that 'Fred left the football and Bernhard is a rhino'.
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.
    0.2::factB.
    0.7::factC.
    
  
    %hop2
    conclusion:-and(factC,factB).
  
    query(conclusion).
    
hypothesis_assertion: 'Fred left the football and Bernhard is a rhino'.