context: There is a very good chance that Mary went to the hallway. It is highly unlikely that Gertrude is a sheep. It is probably the case that Julius is gray. It is certain that if 'Julius is gray' or 'Gertrude is a sheep' or both then Bernhard is yellow. It is likely that if 'Gertrude is a sheep' or 'Julius is gray' or both then Sandra got the milk. There is a better than even chance that if 'Gertrude is a sheep and Julius is gray' then John moved to the office.
hypothesis: It is highly unlikely that 'Gertrude is a sheep' or 'John moved to the office' or both.
valid_hypothesis: It is highly unlikely that 'Gertrude is a sheep' or 'John moved to the office' or both.
invalid_hypothesis: It is probable that 'Gertrude is a sheep' or 'John moved to the office' 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
    0.8::factA.
    0.05::factB.
    0.7::factC.
    %hop1
    1.0::factX:-or(factC,factB).
    0.7::factY:-or(factB,factC).
    0.6::factZ:-and(factB,factC).
  
    %hop2
    conclusion:-or(factB,factZ).
  
    query(conclusion).
    
hypothesis_assertion: 'Gertrude is a sheep' or 'John moved to the office' or both.