context: There is a better than even chance that Mary got the milk. It is improbable that Brian is a frog. There is almost no chance that Lily is a rhino.
hypothesis: There is a better than even chance that 'Mary got the milk' or 'Brian is a frog' or both.
valid_hypothesis: There is a better than even chance that 'Mary got the milk' or 'Brian is a frog' or both.
invalid_hypothesis: It is improbable that 'Mary got the milk' or 'Brian is a frog' 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
    0.6::factA.
    0.1::factB.
    0.02::factC.
    
  
    %hop2
    conclusion:-or(factA,factB).
  
    query(conclusion).
    
hypothesis_assertion: 'Mary got the milk' or 'Brian is a frog' or both.