context: It is probable that Sandra took the football. It is almost certain that Daniel dropped the apple. It is certain that Brian is a swan.
hypothesis: It is impossible that 'Sandra took the football and Daniel dropped the apple'.
valid_hypothesis: It is probable that 'Sandra took the football and Daniel dropped the apple'.
invalid_hypothesis: It is impossible that 'Sandra took the football and Daniel dropped 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
    0.7::factA.
    0.95::factB.
    1.0::factC.
    
  
    %hop2
    conclusion:-and(factA,factB).
  
    query(conclusion).
    
hypothesis_assertion: 'Sandra took the football and Daniel dropped the apple'.