context: It is improbable that Brian is yellow. It is certain that Mary got the football. It is unlikely that Gertrude is a mouse.
hypothesis: There is little chance that 'Gertrude is a mouse' or 'Mary got the football' or both.
valid_hypothesis: It is certain that 'Gertrude is a mouse' or 'Mary got the football' or both.
invalid_hypothesis: There is little chance that 'Gertrude is a mouse' or 'Mary got the football' 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
    0.1::factA.
    1.0::factB.
    0.2::factC.
    
  
    %hop2
    conclusion:-or(factC,factB).
  
    query(conclusion).
    
hypothesis_assertion: 'Gertrude is a mouse' or 'Mary got the football' or both.