It is probably the case that Lily is yellow. It is unlikely that Mary went to the office. It is improbable that Bernhard is green. It is likely that if either 'Lily is yellow' or 'Bernhard is green' but not both then Julius is gray. It is probable that if either 'Bernhard is green' or 'Lily is yellow' but not both then Emily is a mouse. We believe that if 'Bernhard is green' or 'Lily is yellow' or both then John dropped the apple.
It is highly likely that either 'Julius is gray' or 'Lily is yellow' but not both.
It is probably not the case that either 'Julius is gray' or 'Lily is yellow' but not both.
It is highly likely that either 'Julius is gray' or 'Lily is yellow' but not both.

  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.
  0.2::factB.
  0.1::factC.
  %hop1
  0.7::factX:-xor(factA,factC).
  0.7::factY:-xor(factC,factA).
  0.75::factZ:-or(factC,factA).

  %hop2
  conclusion:-xor(factX,factA).

  query(conclusion).
  
Either 'Julius is gray' or 'Lily is yellow' but not both.