context: It is certain that John went to the hallway. There is almost no chance that Emily is a mouse. Chances are slight that Yann is tired.
hypothesis: There is little chance that 'John went to the hallway and Yann is tired'.
valid_hypothesis: There is little chance that 'John went to the hallway and Yann is tired'.
invalid_hypothesis: It is certain that 'John went to the hallway and Yann is tired'.
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
    1.0::factA.
    0.02::factB.
    0.1::factC.
    
  
    %hop2
    conclusion:-and(factA,factC).
  
    query(conclusion).
    
hypothesis_assertion: 'John went to the hallway and Yann is tired'.