context: It is probably the case that Sandra left the apple. Chances are about even that Bernhard is a swan. It is almost certain that Brian is white.
hypothesis: Chances are slight that 'Brian is white' or 'Sandra left the apple' or both.
valid_hypothesis: It is certain that 'Brian is white' or 'Sandra left the apple' or both.
invalid_hypothesis: Chances are slight that 'Brian is white' or 'Sandra left the apple' 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.
    0.5::factB.
    0.95::factC.
    
  
    %hop2
    conclusion:-or(factC,factA).
  
    query(conclusion).
    
hypothesis_assertion: 'Brian is white' or 'Sandra left the apple' or both.