context: It is highly likely that John dropped the apple. There is a better than even chance that Mary went to the hallway. It is almost certain that Bernhard is a lion.
hypothesis: It is almost certain that 'John dropped the apple and Mary went to the hallway'.
valid_hypothesis: Chances are about even that 'John dropped the apple and Mary went to the hallway'.
invalid_hypothesis: It is almost certain that 'John dropped the apple and Mary went to the hallway'.
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
    0.9::factA.
    0.6::factB.
    0.95::factC.
    
  
    %hop2
    conclusion:-and(factA,factB).
  
    query(conclusion).
    
hypothesis_assertion: 'John dropped the apple and Mary went to the hallway'.