context: Chances are slight that John got the milk. Chances are slight that Julius is yellow. It is improbable that Emily is a wolf. It is highly likely that if 'Emily is a wolf and John got the milk' then Greg is a lion. It is probably not the case that if either 'Emily is a wolf' or 'John got the milk' but not both then Bernhard is gray. It is highly likely that if 'Julius is yellow' or 'Emily is a wolf' or both then Mary went to the kitchen.
hypothesis: There is almost no chance that 'Bernhard is gray and Emily is a wolf'.
valid_hypothesis: There is almost no chance that 'Bernhard is gray and Emily is a wolf'.
invalid_hypothesis: It is probable that 'Bernhard is gray and Emily is a wolf'.
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.
    0.1::factB.
    0.1::factC.
    %hop1
    0.9::factX:-and(factC,factA).
    0.25::factY:-xor(factC,factA).
    0.9::factZ:-or(factB,factC).
  
    %hop2
    conclusion:-and(factY,factC).
  
    query(conclusion).
    
hypothesis_assertion: 'Bernhard is gray and Emily is a wolf'.