context: Chances are about even that Bernhard is a rhino. It is impossible that John took the apple. There is a better than even chance that Mary left the football.
hypothesis: It is probably the case that 'John took the apple and Bernhard is a rhino'.
valid_hypothesis: It is impossible that 'John took the apple and Bernhard is a rhino'.
invalid_hypothesis: It is probably the case that 'John took the apple and Bernhard is a rhino'.
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
    0.5::factA.
    0.0::factB.
    0.6::factC.
    
  
    %hop2
    conclusion:-and(factB,factA).
  
    query(conclusion).
    
hypothesis_assertion: 'John took the apple and Bernhard is a rhino'.