context: It is impossible that Jason is tired. There is almost no chance that John moved to the garden. Chances are slight that Bernhard is a swan. It is probable that if 'John moved to the garden' or 'Bernhard is a swan' or both then Greg is gray. There is almost no chance that if 'John moved to the garden' or 'Bernhard is a swan' or both then Mary left the milk. There is little chance that if 'Bernhard is a swan' or 'John moved to the garden' or both then Lily is a rhino.
hypothesis: Chances are slight that 'Lily is a rhino' or 'Greg is gray' or both.
valid_hypothesis: Chances are slight that 'Lily is a rhino' or 'Greg is gray' or both.
invalid_hypothesis: It is probable that 'Lily is a rhino' or 'Greg is gray' 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
    0.0::factA.
    0.02::factB.
    0.1::factC.
    %hop1
    0.7::factX:-or(factB,factC).
    0.02::factY:-or(factB,factC).
    0.1::factZ:-or(factC,factB).
  
    %hop2
    conclusion:-or(factZ,factX).
  
    query(conclusion).
    
hypothesis_assertion: 'Lily is a rhino' or 'Greg is gray' or both.