context: It is impossible that Gertrude is a mouse. It is probably the case that Mary dropped the apple. We doubt that Bernhard is yellow.
hypothesis: It is likely that 'Mary dropped the apple and Gertrude is a mouse'.
valid_hypothesis: It is impossible that 'Mary dropped the apple and Gertrude is a mouse'.
invalid_hypothesis: It is likely that 'Mary dropped the apple and Gertrude is a mouse'.
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
    0.0::factA.
    0.7::factB.
    0.2::factC.
    
  
    %hop2
    conclusion:-and(factB,factA).
  
    query(conclusion).
    
hypothesis_assertion: 'Mary dropped the apple and Gertrude is a mouse'.