There is a better than even chance that Lily is white. It is highly likely that Daniel left the milk. It is probably not the case that Mary got the football. It is certain that if either 'Daniel left the milk' or 'Lily is white' but not both then John moved to the office. We doubt that if 'Daniel left the milk' or 'Lily is white' or both then Bernhard is yellow. It is impossible that if either 'Mary got the football' or 'Lily is white' but not both then Julius is gray.
It is impossible that 'Julius is gray and Mary got the football'.
It is impossible that 'Julius is gray and Mary got the football'.
We believe that 'Julius is gray and Mary got the football'.

  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
  0.6::factA.
  0.9::factB.
  0.25::factC.
  %hop1
  1.0::factX:-xor(factB,factA).
  0.2::factY:-or(factB,factA).
  0.0::factZ:-xor(factC,factA).

  %hop2
  conclusion:-and(factZ,factC).

  query(conclusion).
  
'Julius is gray and Mary got the football'.