context: It is highly unlikely that Lily is white. There is a very good chance that Jessica is a sheep. It is certain that Greg is a swan. It is certain that if 'Jessica is a sheep and Lily is white' then Daniel put down the milk. There is a better than even chance that if 'Lily is white' or 'Greg is a swan' or both then John moved to the garden. It is highly likely that if either 'Greg is a swan' or 'Jessica is a sheep' but not both then Mary went to the bedroom.
hypothesis: There is almost no chance that 'Greg is a swan and John moved to the garden'.
valid_hypothesis: There is a better than even chance that 'Greg is a swan and John moved to the garden'.
invalid_hypothesis: There is almost no chance that 'Greg is a swan and John moved to the garden'.
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
    0.05::factA.
    0.8::factB.
    1.0::factC.
    %hop1
    1.0::factX:-and(factB,factA).
    0.6::factY:-or(factA,factC).
    0.9::factZ:-xor(factC,factB).
  
    %hop2
    conclusion:-and(factC,factY).
  
    query(conclusion).
    
hypothesis_assertion: 'Greg is a swan and John moved to the garden'.