context: It is probably the case that John moved to the garden. Chances are slight that Bernhard is a swan. It is improbable that Emily is a mouse. It is impossible that if 'Emily is a mouse and John moved to the garden' then Julius is gray. It is impossible that if 'John moved to the garden and Emily is a mouse' then Jeff dropped the apple. We believe that if 'Bernhard is a swan' or 'Emily is a mouse' or both then Mary is in the bathroom.
hypothesis: Chances are slight that either 'Emily is a mouse' or 'Julius is gray' but not both.
valid_hypothesis: Chances are slight that either 'Emily is a mouse' or 'Julius is gray' but not both.
invalid_hypothesis: It is almost certain that either 'Emily is a mouse' or 'Julius is gray' but not 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
    0.7::factA.
    0.1::factB.
    0.1::factC.
    %hop1
    0.0::factX:-and(factC,factA).
    0.0::factY:-and(factA,factC).
    0.75::factZ:-or(factB,factC).
  
    %hop2
    conclusion:-xor(factC,factX).
  
    query(conclusion).
    
hypothesis_assertion: Either 'Emily is a mouse' or 'Julius is gray' but not both.