context: It is almost certain that Gertrude is a sheep. It is improbable that Brian is green. It is highly unlikely that Daniel got the football. There is almost no chance that if either 'Daniel got the football' or 'Brian is green' but not both then Julius is white. We doubt that if either 'Brian is green' or 'Gertrude is a sheep' but not both then Sandra left the milk. There is little chance that if 'Gertrude is a sheep' or 'Brian is green' or both then Mary went to the bedroom.
hypothesis: It is almost certain that 'Gertrude is a sheep' or 'Julius is white' or both.
valid_hypothesis: It is almost certain that 'Gertrude is a sheep' or 'Julius is white' or both.
invalid_hypothesis: It is highly unlikely that 'Gertrude is a sheep' or 'Julius is white' 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
    0.95::factA.
    0.1::factB.
    0.05::factC.
    %hop1
    0.02::factX:-xor(factC,factB).
    0.2::factY:-xor(factB,factA).
    0.1::factZ:-or(factA,factB).
  
    %hop2
    conclusion:-or(factA,factX).
  
    query(conclusion).
    
hypothesis_assertion: 'Gertrude is a sheep' or 'Julius is white' or both.