context: We believe that Gertrude is a wolf. It is likely that Lily is a lion. It is unlikely that Bernhard is green. It is probably the case that if 'Gertrude is a wolf' or 'Lily is a lion' or both then John picked up the milk. There is a very good chance that if either 'Lily is a lion' or 'Gertrude is a wolf' but not both then Greg is a rhino. It is improbable that if 'Bernhard is green' or 'Lily is a lion' or both then Julius is white.
hypothesis: We believe that 'Gertrude is a wolf' or 'Julius is white' or both.
valid_hypothesis: We believe that 'Gertrude is a wolf' or 'Julius is white' or both.
invalid_hypothesis: There is almost no chance that 'Gertrude is a wolf' 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
    0.75::factA.
    0.7::factB.
    0.2::factC.
    %hop1
    0.7::factX:-or(factA,factB).
    0.8::factY:-xor(factB,factA).
    0.1::factZ:-or(factC,factB).
  
    %hop2
    conclusion:-or(factA,factZ).
  
    query(conclusion).
    
hypothesis_assertion: 'Gertrude is a wolf' or 'Julius is white' or both.