context: It is improbable that Jeff went to the hallway. It is probably not the case that Sandra got the milk. We believe that Bernhard is a swan. It is almost certain that if 'Bernhard is a swan' or 'Jeff went to the hallway' or both then Greg is green. It is probably the case that if 'Sandra got the milk' or 'Bernhard is a swan' or both then Winona is a cat. There is almost no chance that if either 'Sandra got the milk' or 'Jeff went to the hallway' but not both then John moved to the office.
hypothesis: There is a very good chance that 'John moved to the office and Greg is green'.
valid_hypothesis: It is impossible that 'John moved to the office and Greg is green'.
invalid_hypothesis: There is a very good chance that 'John moved to the office and Greg is green'.
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
    0.1::factA.
    0.25::factB.
    0.75::factC.
    %hop1
    0.95::factX:-or(factC,factA).
    0.7::factY:-or(factB,factC).
    0.02::factZ:-xor(factB,factA).
  
    %hop2
    conclusion:-and(factZ,factX).
  
    query(conclusion).
    
hypothesis_assertion: 'John moved to the office and Greg is green'.