context: It is highly unlikely that John went to the hallway. There is a very good chance that Bernhard is yellow. There is little chance that Gertrude is a cat.
hypothesis: We believe that 'John went to the hallway and Gertrude is a cat'.
valid_hypothesis: It is impossible that 'John went to the hallway and Gertrude is a cat'.
invalid_hypothesis: We believe that 'John went to the hallway and Gertrude is a cat'.
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
    0.05::factA.
    0.8::factB.
    0.1::factC.
    
  
    %hop2
    conclusion:-and(factA,factC).
  
    query(conclusion).
    
hypothesis_assertion: 'John went to the hallway and Gertrude is a cat'.