context: It is unlikely that Daniel left the milk. It is almost certain that Gertrude is a mouse. It is improbable that John moved to the office. It is probable that if 'Gertrude is a mouse and Daniel left the milk' then Bernhard is green. There is little chance that if either 'Daniel left the milk' or 'John moved to the office' but not both then Brian is a swan. It is probably not the case that if either 'Daniel left the milk' or 'Gertrude is a mouse' but not both then Julius is a frog.
hypothesis: It is probably not the case that either 'Gertrude is a mouse' or 'Daniel left the milk' but not both.
valid_hypothesis: We believe that either 'Gertrude is a mouse' or 'Daniel left the milk' but not both.
invalid_hypothesis: It is probably not the case that either 'Gertrude is a mouse' or 'Daniel left the milk' but not 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
    0.2::factA.
    0.95::factB.
    0.1::factC.
    %hop1
    0.7::factX:-and(factB,factA).
    0.1::factY:-xor(factA,factC).
    0.25::factZ:-xor(factA,factB).
  
    %hop2
    conclusion:-xor(factB,factA).
  
    query(conclusion).
    
hypothesis_assertion: Either 'Gertrude is a mouse' or 'Daniel left the milk' but not both.