context: It is improbable that Lily is yellow. We believe that Brian is a lion. We believe that Sandra left the football.
hypothesis: There is a very good chance that 'Sandra left the football and Lily is yellow'.
valid_hypothesis: Chances are slight that 'Sandra left the football and Lily is yellow'.
invalid_hypothesis: There is a very good chance that 'Sandra left the football and Lily is yellow'.
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
    0.1::factA.
    0.75::factB.
    0.75::factC.
    
  
    %hop2
    conclusion:-and(factC,factA).
  
    query(conclusion).
    
hypothesis_assertion: 'Sandra left the football and Lily is yellow'.