context: It is probably the case that Bernhard is a lion. It is probably not the case that Sandra got the milk. There is a very good chance that Julius is gray.
hypothesis: It is almost certain that 'Julius is gray' or 'Bernhard is a lion' or both.
valid_hypothesis: It is almost certain that 'Julius is gray' or 'Bernhard is a lion' or both.
invalid_hypothesis: It is unlikely that 'Julius is gray' or 'Bernhard is a lion' or both.
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
    0.7::factA.
    0.25::factB.
    0.8::factC.
    
  
    %hop2
    conclusion:-or(factC,factA).
  
    query(conclusion).
    
hypothesis_assertion: 'Julius is gray' or 'Bernhard is a lion' or both.